John T. Repke, MD

A Yes, in this study, but the findings may not apply to the entire US population. Treatment reduced serious perinatal morbidity and improved the mother’s quality of life.

Expert Commentary

Gestational diabetes mellitus has occasionally seemed like a name looking for a disease. Screening recommendations and diagnostic criteria have been debated and changed, and it has appeared that, regardless of intervention, outcomes are the same.

This randomized trial sheds new light on the effectiveness of diagnosis and intervention, but some issues remain unclear—a fact pointed out in an editorial accompanying the study.¹ My interpretation is similar to the one outlined in that editorial.

Nonstandard diagnostic criterion

Though the results are compelling and the randomized clinical trial model lends credence to the conclusions, the diagnostic test and criterion for diagnosing gestational diabetes (75-g glucose load with a 2-hour value >140 mg/dL) are not the standard in the United States, so the results may not be applicable in the US.

A real difference, or coincidence?

More adverse perinatal outcomes were reported among the “routine care” group than the intervention group. The authors did not clarify, however, whether the 5 perinatal deaths in the routine care group could be attributed to gestational diabetes or were coincidental. Also, although the difference in birth weight was statistically significant (mean weight of 3,335 g in the intervention group versus 3,482 g for routine care; P<.001 i am unsure of the clinical importance this difference.>

Other variables listed under adverse outcomes included 5-minute Apgar scores of less than 7 and admission to the NICU, both of which can be based on highly subjective criteria. No information was offered about whether—and how—such decision-making was standardized.

Was it ethical to ignore screening?

US practitioners would not ignore the results of a gestational diabetes screening test, as in this study (neither practitioners nor patients were made aware of the diagnosis). Thus, the findings shed little light on real-world practices of US ObGyns.

We also lack information on the cost (in dollar terms and morbidity) of any false-positive results.

Stick to ACOG guidelines

Gestational diabetes is an increasing problem, compounded by the obesity epidemic. Failing to screen patients, or ignoring a positive screen, would seem ill-advised, and glucose control would seem to be a prudent way to minimize maternal and perinatal morbidity. We need to determine the appropriate screening tools and diagnostic criteria, glucose values that should prompt intervention, and the optimal form of intervention, be it through diet alone or in combination with oral hypoglycemics or insulin.

Until these questions are resolved (probably not within this decade), I suggest we continue to follow ACOG guidelines for diagnosis and management.²

Dr. Legro has received grant support from the American Heart Association, Crown, General Mills, and Pfizer and is a consultant for Abbott and Ortho-McNeil. Dr. Greenberg and Dr. Repke report no financial relationships relevant to these articles.

A Yes, in this study, but the findings may not apply to the entire US population. Treatment reduced serious perinatal morbidity and improved the mother’s quality of life.

Expert Commentary

Gestational diabetes mellitus has occasionally seemed like a name looking for a disease. Screening recommendations and diagnostic criteria have been debated and changed, and it has appeared that, regardless of intervention, outcomes are the same.

This randomized trial sheds new light on the effectiveness of diagnosis and intervention, but some issues remain unclear—a fact pointed out in an editorial accompanying the study.¹ My interpretation is similar to the one outlined in that editorial.

Nonstandard diagnostic criterion

Though the results are compelling and the randomized clinical trial model lends credence to the conclusions, the diagnostic test and criterion for diagnosing gestational diabetes (75-g glucose load with a 2-hour value >140 mg/dL) are not the standard in the United States, so the results may not be applicable in the US.

A real difference, or coincidence?

More adverse perinatal outcomes were reported among the “routine care” group than the intervention group. The authors did not clarify, however, whether the 5 perinatal deaths in the routine care group could be attributed to gestational diabetes or were coincidental. Also, although the difference in birth weight was statistically significant (mean weight of 3,335 g in the intervention group versus 3,482 g for routine care; P<.001 i am unsure of the clinical importance this difference.>

Other variables listed under adverse outcomes included 5-minute Apgar scores of less than 7 and admission to the NICU, both of which can be based on highly subjective criteria. No information was offered about whether—and how—such decision-making was standardized.

Was it ethical to ignore screening?

US practitioners would not ignore the results of a gestational diabetes screening test, as in this study (neither practitioners nor patients were made aware of the diagnosis). Thus, the findings shed little light on real-world practices of US ObGyns.

We also lack information on the cost (in dollar terms and morbidity) of any false-positive results.

Stick to ACOG guidelines

Gestational diabetes is an increasing problem, compounded by the obesity epidemic. Failing to screen patients, or ignoring a positive screen, would seem ill-advised, and glucose control would seem to be a prudent way to minimize maternal and perinatal morbidity. We need to determine the appropriate screening tools and diagnostic criteria, glucose values that should prompt intervention, and the optimal form of intervention, be it through diet alone or in combination with oral hypoglycemics or insulin.

Until these questions are resolved (probably not within this decade), I suggest we continue to follow ACOG guidelines for diagnosis and management.²

Dr. Legro has received grant support from the American Heart Association, Crown, General Mills, and Pfizer and is a consultant for Abbott and Ortho-McNeil. Dr. Greenberg and Dr. Repke report no financial relationships relevant to these articles.

A Yes, in this study, but the findings may not apply to the entire US population. Treatment reduced serious perinatal morbidity and improved the mother’s quality of life.

Expert Commentary

Gestational diabetes mellitus has occasionally seemed like a name looking for a disease. Screening recommendations and diagnostic criteria have been debated and changed, and it has appeared that, regardless of intervention, outcomes are the same.

This randomized trial sheds new light on the effectiveness of diagnosis and intervention, but some issues remain unclear—a fact pointed out in an editorial accompanying the study.¹ My interpretation is similar to the one outlined in that editorial.

Nonstandard diagnostic criterion

Though the results are compelling and the randomized clinical trial model lends credence to the conclusions, the diagnostic test and criterion for diagnosing gestational diabetes (75-g glucose load with a 2-hour value >140 mg/dL) are not the standard in the United States, so the results may not be applicable in the US.

A real difference, or coincidence?

More adverse perinatal outcomes were reported among the “routine care” group than the intervention group. The authors did not clarify, however, whether the 5 perinatal deaths in the routine care group could be attributed to gestational diabetes or were coincidental. Also, although the difference in birth weight was statistically significant (mean weight of 3,335 g in the intervention group versus 3,482 g for routine care; P<.001 i am unsure of the clinical importance this difference.>

Other variables listed under adverse outcomes included 5-minute Apgar scores of less than 7 and admission to the NICU, both of which can be based on highly subjective criteria. No information was offered about whether—and how—such decision-making was standardized.

Was it ethical to ignore screening?

US practitioners would not ignore the results of a gestational diabetes screening test, as in this study (neither practitioners nor patients were made aware of the diagnosis). Thus, the findings shed little light on real-world practices of US ObGyns.

We also lack information on the cost (in dollar terms and morbidity) of any false-positive results.

Stick to ACOG guidelines

Gestational diabetes is an increasing problem, compounded by the obesity epidemic. Failing to screen patients, or ignoring a positive screen, would seem ill-advised, and glucose control would seem to be a prudent way to minimize maternal and perinatal morbidity. We need to determine the appropriate screening tools and diagnostic criteria, glucose values that should prompt intervention, and the optimal form of intervention, be it through diet alone or in combination with oral hypoglycemics or insulin.

Until these questions are resolved (probably not within this decade), I suggest we continue to follow ACOG guidelines for diagnosis and management.²

Dr. Legro has received grant support from the American Heart Association, Crown, General Mills, and Pfizer and is a consultant for Abbott and Ortho-McNeil. Dr. Greenberg and Dr. Repke report no financial relationships relevant to these articles.

Life-threatening obstetric hypertensive emergencies cannot be entirely prevented, but the risk of serious complications can be minimized.

The spectrum of hypertensive disease that can complicate pregnancy is broad—ranging from so-called “white coat” hypertension to gestational hypertension, chronic hypertension, chronic hypertension with superimposed preeclampsia, to preeclampsia.

Particularly challenging, however, is hypertension in pregnancy that becomes severe enough to qualify as a hypertensive crisis, bringing on immediate risk to both fetus and mother.

Risk may evolve over days—or hours—and may present as worsening blood pressure culminating in hypertensive crisis. Fetal morbidity and mortality, including placental abruption and acute fetal distress, are often directly linked to the maternal risks of hypertensive encephalopathy and cerebrovascular accident.

Placental abruption and fetal distress are common with severe hypertension even without encephalopathy and cerebrovascular accident. Abruption is unpredictable and potentially catastrophic, even with intense monitoring.

Aggressive BP control, while fundamental, needs to be balanced against the risks to both mother and fetus of overcorrection and undercorrection.

Defining a crisis

What truly defines hypertensive obstetric emergency is a matter of some debate.

Persistent blood pressures above 200 mm Hg systolic and/or 115 mm Hg diastolic qualify, but some have advocated 160/110 mm Hg as the threshold for emergent treatment of blood pressure. Others suggest that the rate of change in blood pressure is what precipitates the crisis, as opposed to the absolute blood pressure readings.

Why BP control is critical

The true pathophysiology of hypertensive crisis in pregnancy is obscure, but undoubtedly shares characteristics seen in the nonpregnant adult. Diagnosing a hypertensive emergency in the nonpregnant adult, in contrast to diagnosis of an obstetric hypertensive emergency, relies more on clinical manifestations of hypertension than on absolute blood pressure level.¹

Pathophysiology

In the nonpregnant adult, 2 independent processes are thought to be necessary for the full-blown encephalopathic picture: dilation of the cerebral vasculature and fibrinoid necrosis. In the initial phases of severe hypertension, the cerebral vessels constrict to maintain cerebral perfusion pressure in the face of increased systemic arterial pressure. Once the limits of autoregulation are exceeded, reflex cerebral dilatation and resultant overperfusion lead to microvascular damage, exudation, microthrombus formation, and increased intracranial pressure, which in turn result in the encephalopathic picture.

In pregnancy, a prominent feature seems to be loss of cerebrovascular autoregulation, resulting in hypertensive encephalopathy once the upper limits of cerebral perfusion pressures are exceeded.² Rapid control of blood pressure is needed even more because of the risks of placental abruption and stroke (See). Stroke is of special concern in the setting of thrombocytopenia or HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome. Cerebral edema may be more closely associated with endothelial cell injury than with blood pressure,³ although control of blood pressure may help minimize the endothelial cell injury.

Minimizing organ damage

First, restore normal BP

The most important clinical objective for treatment of acute hypertensive crisis in the nonpregnant adult is to minimize end organ damage, especially to the brain⁴; in obstetric cases, the major morbidity and mortality result from cardiac and renal, as well as cerebrovascular damage. Fetal morbidity and mortality, although not inconsequential, is often directly linked to the maternal condition, and therefore management is based on the triad of diagnosis, stabilization, and delivery.

The physiological dysfunctions described above are best tended to by aggressively controlling blood pressure. With restoration of acceptable blood pressures, generally in the range of 140 to 150 mm Hg systolic and 90 to 100 mm Hg diastolic, cardiac dysfunction begins to reverse, renal function tends to improve, and the restoration of cerebral autoregulatory capability lessens (but does not eliminate) the likelihood of stroke.

Rule out other causes

The foremost goal of therapy for malignant hypertension is to restore normal blood pressure, which depends on correct diagnosis so that appropriate pharmacotherapy may be initiated. For example, clinical situations that could cause malignant hypertension include such disparate entities as acute aortic dissection, acute left ventricular failure, pheochromocytoma, monoamine oxidase inhibitor–food (tyramine) interactions, eclampsia, and acute cocaine intoxication, to name but a few.

Frequently, chronic hypertension or severe preeclampsia defines the underlying “cause” of the severe hypertension, but consideration of other diagnoses, such as uncontrolled hyperthyroidism or pheochromocytoma, should not be overlooked. For example, in pheochromocytoma blood pressures tend to be paroxysmal with wide fluctuations. In hyperthyroidism, clinical signs or symptoms would be expected to accompany the clinical picture, such as the presence of proptosis, exophthalmos, lid lag, tremor, elevated temperature, and a wide pulse pressure, to name but a few.

 

Regimens to lower BP safely

It is imperative that blood pressure be lowered in a measured and safe manner, not to exceed a drop of 25% to 30% in the first 60 minutes, and not to drop below 150/95.⁴ Medications available for blood pressure reduction are listed in the Clip-and-save chart above.⁵

Every effort must be made to not overcorrect the hypertension. Too swift or too dramatic a reduction in blood pressure can have untoward consequences for both mother and fetus, including but not limited to acute fetal distress secondary to uteroplacental underperfusion, and the possibility of maternal myocardial or cerebral infarction. For these reasons, short-acting intravenous agents are recommended to treat hypertensive emergencies, and oral or sublingual compounds are to be avoided because they are more likely to cause precipitous and erratic drops in blood pressure.⁶

Pulmonary edema is not uncommon, due to capillary leakage and myocardial dysfunction. Aggressive use of furosemide along with a rapidly acting antihypertensive drug will best allow for improvement of the clinical picture in a timely manner.

Acute management steps

Critical care facilities required. During the acute management phase, patients should be cared for in an intensive care unit (or a labor and delivery unit with critical care capabilities) under the direction of physicians skilled in managing critically ill patients. In most institutions, such management will include participation of anesthesiologists, maternalfetal medicine specialists, and nurses with critical care expertise.

Delivery considerations. During initial management, the patient should have continuous fetal heart rate monitoring. Under such extreme circumstances, it is often not possible to prolong a pregnancy that is remote from term. Delivery decisions will need to balance prematurity risks against maternal risks of continuing the pregnancy.

Hypertension is not a contraindication to glucocorticoids for accelerating lung maturation in the fetus and minimizing neonatal risk of intracranial hemorrhage and necrotizing enterocolitis.⁷ Adjusting for gestational age, neonates of preeclamptic mothers are afforded no additional maturity compared with neonates born prematurely for other reasons. Delay of delivery for 48 to 72 hours may not be possible in many cases, however. Once the patient is stabilized, delivery must be considered.

Start magnesium sulfate, continue antihypertensives

At this point, it is prudent to start magnesium sulfate to prevent eclampsia. In most cases, however, excluding a diagnosis of preeclampsia in a timely manner is nearly impossible. Under these circumstances, magnesium sulfate is recommended, in addition to continued antihypertensive medications, to maintain BP control.

Magnesium sulfate is best administered intravenously, preferably through an infusion pump apparatus. A loading dose of 4 to 6 g (I prefer 6 g) is given as a 20% solution over 15 to 20 minutes, and then a continuous infusion may be initiated at a rate that depends on the patient’s renal function. In a patient with normal renal function, a rate of 2 g per hour is appropriate, but may need to be reduced if acute renal failure ensues.

In a report of 3 recent cases, investigators found magnesium sulfate was beneficial for controlling the clinical symptoms of pheochromocytoma when conventional therapy was unsuccessful. The presenting symptoms of these nonpregnant patients included hypertensive encephalopathy (2 patients) and catecholamine-induced cardiomyopathy (1 patient).⁶

In general, however, the role of magnesium sulfate should be for preventing progression to eclampsia, and not for acute blood pressure control.

Delivery decisions

Vaginal delivery is often less hemodynamically stressful for the mother, but not always practical. Many cases are remote from term with the fetus in a nonvertex presentation, or the uterine cervix is unfavorable for induction, or a protracted attempt at labor induction may not be prudent.

Under such circumstances, cesarean delivery must be considered and may be preferable. The reasons relate to the underlying maternal condition that often includes some degree of uteroplacental insufficiency. Altered placental function, combined with extreme prematurity, often results in the fetus being unable to tolerate labor for very long, necessitating emergent cesarean under potentially less controlled circumstances. The anesthesiologist and others on the critical care team must review the optimal anesthesia technique.

In most circumstances, and in the absence of coagulopathy, regional anesthesia affords the best results. When regional anesthesia is not an option, balanced general endotracheal anesthesia with antihypertensive premedication using a short-acting agent may be the safest alternative.

Maintain postpartum vigil

With delivery of the fetus, there may be a temptation to be less rigorous in maintaining blood pressure control during the post-partum period. In patients with chronic hypertension without superimposed preeclampsia, this may be acceptable, as these patients better tolerate higher blood pressures and still maintain appropriate cerebral vascular autoregulation.

 

For women who were previously normotensive, or who had superimposed preeclampsia, more rigorous control of blood pressure is recommended, especially if they show any degree of thrombocytopenia or pulmonary edema. (See Clip & save: Stepwise drug therapy for obstetric hypertensive crisis) The rationale relates to cerebral perfusion pressures and risk of stroke in these susceptible women, if thresholds are exceeded, and to the risk of worsening pulmonary edema in the setting of increased capillary hydrostatic pressure and reduced colloid osmotic pressure.

Additionally, continuation of magnesium sulfate is recommended for patients with superimposed preeclampsia until obvious signs of disease resolution, and for a minimum of 24 hours.

The author reports no financial relationships relevant to this article.

Life-threatening obstetric hypertensive emergencies cannot be entirely prevented, but the risk of serious complications can be minimized.

The spectrum of hypertensive disease that can complicate pregnancy is broad—ranging from so-called “white coat” hypertension to gestational hypertension, chronic hypertension, chronic hypertension with superimposed preeclampsia, to preeclampsia.

Particularly challenging, however, is hypertension in pregnancy that becomes severe enough to qualify as a hypertensive crisis, bringing on immediate risk to both fetus and mother.

Risk may evolve over days—or hours—and may present as worsening blood pressure culminating in hypertensive crisis. Fetal morbidity and mortality, including placental abruption and acute fetal distress, are often directly linked to the maternal risks of hypertensive encephalopathy and cerebrovascular accident.

Placental abruption and fetal distress are common with severe hypertension even without encephalopathy and cerebrovascular accident. Abruption is unpredictable and potentially catastrophic, even with intense monitoring.

Aggressive BP control, while fundamental, needs to be balanced against the risks to both mother and fetus of overcorrection and undercorrection.

Defining a crisis

What truly defines hypertensive obstetric emergency is a matter of some debate.

Persistent blood pressures above 200 mm Hg systolic and/or 115 mm Hg diastolic qualify, but some have advocated 160/110 mm Hg as the threshold for emergent treatment of blood pressure. Others suggest that the rate of change in blood pressure is what precipitates the crisis, as opposed to the absolute blood pressure readings.

Why BP control is critical

The true pathophysiology of hypertensive crisis in pregnancy is obscure, but undoubtedly shares characteristics seen in the nonpregnant adult. Diagnosing a hypertensive emergency in the nonpregnant adult, in contrast to diagnosis of an obstetric hypertensive emergency, relies more on clinical manifestations of hypertension than on absolute blood pressure level.¹

Pathophysiology

In the nonpregnant adult, 2 independent processes are thought to be necessary for the full-blown encephalopathic picture: dilation of the cerebral vasculature and fibrinoid necrosis. In the initial phases of severe hypertension, the cerebral vessels constrict to maintain cerebral perfusion pressure in the face of increased systemic arterial pressure. Once the limits of autoregulation are exceeded, reflex cerebral dilatation and resultant overperfusion lead to microvascular damage, exudation, microthrombus formation, and increased intracranial pressure, which in turn result in the encephalopathic picture.

In pregnancy, a prominent feature seems to be loss of cerebrovascular autoregulation, resulting in hypertensive encephalopathy once the upper limits of cerebral perfusion pressures are exceeded.² Rapid control of blood pressure is needed even more because of the risks of placental abruption and stroke (See). Stroke is of special concern in the setting of thrombocytopenia or HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome. Cerebral edema may be more closely associated with endothelial cell injury than with blood pressure,³ although control of blood pressure may help minimize the endothelial cell injury.

Minimizing organ damage

First, restore normal BP

The most important clinical objective for treatment of acute hypertensive crisis in the nonpregnant adult is to minimize end organ damage, especially to the brain⁴; in obstetric cases, the major morbidity and mortality result from cardiac and renal, as well as cerebrovascular damage. Fetal morbidity and mortality, although not inconsequential, is often directly linked to the maternal condition, and therefore management is based on the triad of diagnosis, stabilization, and delivery.

The physiological dysfunctions described above are best tended to by aggressively controlling blood pressure. With restoration of acceptable blood pressures, generally in the range of 140 to 150 mm Hg systolic and 90 to 100 mm Hg diastolic, cardiac dysfunction begins to reverse, renal function tends to improve, and the restoration of cerebral autoregulatory capability lessens (but does not eliminate) the likelihood of stroke.

Rule out other causes

The foremost goal of therapy for malignant hypertension is to restore normal blood pressure, which depends on correct diagnosis so that appropriate pharmacotherapy may be initiated. For example, clinical situations that could cause malignant hypertension include such disparate entities as acute aortic dissection, acute left ventricular failure, pheochromocytoma, monoamine oxidase inhibitor–food (tyramine) interactions, eclampsia, and acute cocaine intoxication, to name but a few.

Frequently, chronic hypertension or severe preeclampsia defines the underlying “cause” of the severe hypertension, but consideration of other diagnoses, such as uncontrolled hyperthyroidism or pheochromocytoma, should not be overlooked. For example, in pheochromocytoma blood pressures tend to be paroxysmal with wide fluctuations. In hyperthyroidism, clinical signs or symptoms would be expected to accompany the clinical picture, such as the presence of proptosis, exophthalmos, lid lag, tremor, elevated temperature, and a wide pulse pressure, to name but a few.

 

Regimens to lower BP safely

It is imperative that blood pressure be lowered in a measured and safe manner, not to exceed a drop of 25% to 30% in the first 60 minutes, and not to drop below 150/95.⁴ Medications available for blood pressure reduction are listed in the Clip-and-save chart above.⁵

Every effort must be made to not overcorrect the hypertension. Too swift or too dramatic a reduction in blood pressure can have untoward consequences for both mother and fetus, including but not limited to acute fetal distress secondary to uteroplacental underperfusion, and the possibility of maternal myocardial or cerebral infarction. For these reasons, short-acting intravenous agents are recommended to treat hypertensive emergencies, and oral or sublingual compounds are to be avoided because they are more likely to cause precipitous and erratic drops in blood pressure.⁶

Pulmonary edema is not uncommon, due to capillary leakage and myocardial dysfunction. Aggressive use of furosemide along with a rapidly acting antihypertensive drug will best allow for improvement of the clinical picture in a timely manner.

Acute management steps

Critical care facilities required. During the acute management phase, patients should be cared for in an intensive care unit (or a labor and delivery unit with critical care capabilities) under the direction of physicians skilled in managing critically ill patients. In most institutions, such management will include participation of anesthesiologists, maternalfetal medicine specialists, and nurses with critical care expertise.

Delivery considerations. During initial management, the patient should have continuous fetal heart rate monitoring. Under such extreme circumstances, it is often not possible to prolong a pregnancy that is remote from term. Delivery decisions will need to balance prematurity risks against maternal risks of continuing the pregnancy.

Hypertension is not a contraindication to glucocorticoids for accelerating lung maturation in the fetus and minimizing neonatal risk of intracranial hemorrhage and necrotizing enterocolitis.⁷ Adjusting for gestational age, neonates of preeclamptic mothers are afforded no additional maturity compared with neonates born prematurely for other reasons. Delay of delivery for 48 to 72 hours may not be possible in many cases, however. Once the patient is stabilized, delivery must be considered.

Start magnesium sulfate, continue antihypertensives

At this point, it is prudent to start magnesium sulfate to prevent eclampsia. In most cases, however, excluding a diagnosis of preeclampsia in a timely manner is nearly impossible. Under these circumstances, magnesium sulfate is recommended, in addition to continued antihypertensive medications, to maintain BP control.

Magnesium sulfate is best administered intravenously, preferably through an infusion pump apparatus. A loading dose of 4 to 6 g (I prefer 6 g) is given as a 20% solution over 15 to 20 minutes, and then a continuous infusion may be initiated at a rate that depends on the patient’s renal function. In a patient with normal renal function, a rate of 2 g per hour is appropriate, but may need to be reduced if acute renal failure ensues.

In a report of 3 recent cases, investigators found magnesium sulfate was beneficial for controlling the clinical symptoms of pheochromocytoma when conventional therapy was unsuccessful. The presenting symptoms of these nonpregnant patients included hypertensive encephalopathy (2 patients) and catecholamine-induced cardiomyopathy (1 patient).⁶

In general, however, the role of magnesium sulfate should be for preventing progression to eclampsia, and not for acute blood pressure control.

Delivery decisions

Vaginal delivery is often less hemodynamically stressful for the mother, but not always practical. Many cases are remote from term with the fetus in a nonvertex presentation, or the uterine cervix is unfavorable for induction, or a protracted attempt at labor induction may not be prudent.

Under such circumstances, cesarean delivery must be considered and may be preferable. The reasons relate to the underlying maternal condition that often includes some degree of uteroplacental insufficiency. Altered placental function, combined with extreme prematurity, often results in the fetus being unable to tolerate labor for very long, necessitating emergent cesarean under potentially less controlled circumstances. The anesthesiologist and others on the critical care team must review the optimal anesthesia technique.

In most circumstances, and in the absence of coagulopathy, regional anesthesia affords the best results. When regional anesthesia is not an option, balanced general endotracheal anesthesia with antihypertensive premedication using a short-acting agent may be the safest alternative.

Maintain postpartum vigil

With delivery of the fetus, there may be a temptation to be less rigorous in maintaining blood pressure control during the post-partum period. In patients with chronic hypertension without superimposed preeclampsia, this may be acceptable, as these patients better tolerate higher blood pressures and still maintain appropriate cerebral vascular autoregulation.

 

For women who were previously normotensive, or who had superimposed preeclampsia, more rigorous control of blood pressure is recommended, especially if they show any degree of thrombocytopenia or pulmonary edema. (See Clip & save: Stepwise drug therapy for obstetric hypertensive crisis) The rationale relates to cerebral perfusion pressures and risk of stroke in these susceptible women, if thresholds are exceeded, and to the risk of worsening pulmonary edema in the setting of increased capillary hydrostatic pressure and reduced colloid osmotic pressure.

Additionally, continuation of magnesium sulfate is recommended for patients with superimposed preeclampsia until obvious signs of disease resolution, and for a minimum of 24 hours.

The author reports no financial relationships relevant to this article.

Life-threatening obstetric hypertensive emergencies cannot be entirely prevented, but the risk of serious complications can be minimized.

The spectrum of hypertensive disease that can complicate pregnancy is broad—ranging from so-called “white coat” hypertension to gestational hypertension, chronic hypertension, chronic hypertension with superimposed preeclampsia, to preeclampsia.

Particularly challenging, however, is hypertension in pregnancy that becomes severe enough to qualify as a hypertensive crisis, bringing on immediate risk to both fetus and mother.

Risk may evolve over days—or hours—and may present as worsening blood pressure culminating in hypertensive crisis. Fetal morbidity and mortality, including placental abruption and acute fetal distress, are often directly linked to the maternal risks of hypertensive encephalopathy and cerebrovascular accident.

Placental abruption and fetal distress are common with severe hypertension even without encephalopathy and cerebrovascular accident. Abruption is unpredictable and potentially catastrophic, even with intense monitoring.

Aggressive BP control, while fundamental, needs to be balanced against the risks to both mother and fetus of overcorrection and undercorrection.

Defining a crisis

What truly defines hypertensive obstetric emergency is a matter of some debate.

Persistent blood pressures above 200 mm Hg systolic and/or 115 mm Hg diastolic qualify, but some have advocated 160/110 mm Hg as the threshold for emergent treatment of blood pressure. Others suggest that the rate of change in blood pressure is what precipitates the crisis, as opposed to the absolute blood pressure readings.

Why BP control is critical

The true pathophysiology of hypertensive crisis in pregnancy is obscure, but undoubtedly shares characteristics seen in the nonpregnant adult. Diagnosing a hypertensive emergency in the nonpregnant adult, in contrast to diagnosis of an obstetric hypertensive emergency, relies more on clinical manifestations of hypertension than on absolute blood pressure level.¹

Pathophysiology

In the nonpregnant adult, 2 independent processes are thought to be necessary for the full-blown encephalopathic picture: dilation of the cerebral vasculature and fibrinoid necrosis. In the initial phases of severe hypertension, the cerebral vessels constrict to maintain cerebral perfusion pressure in the face of increased systemic arterial pressure. Once the limits of autoregulation are exceeded, reflex cerebral dilatation and resultant overperfusion lead to microvascular damage, exudation, microthrombus formation, and increased intracranial pressure, which in turn result in the encephalopathic picture.

In pregnancy, a prominent feature seems to be loss of cerebrovascular autoregulation, resulting in hypertensive encephalopathy once the upper limits of cerebral perfusion pressures are exceeded.² Rapid control of blood pressure is needed even more because of the risks of placental abruption and stroke (See). Stroke is of special concern in the setting of thrombocytopenia or HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome. Cerebral edema may be more closely associated with endothelial cell injury than with blood pressure,³ although control of blood pressure may help minimize the endothelial cell injury.

Minimizing organ damage

First, restore normal BP

The most important clinical objective for treatment of acute hypertensive crisis in the nonpregnant adult is to minimize end organ damage, especially to the brain⁴; in obstetric cases, the major morbidity and mortality result from cardiac and renal, as well as cerebrovascular damage. Fetal morbidity and mortality, although not inconsequential, is often directly linked to the maternal condition, and therefore management is based on the triad of diagnosis, stabilization, and delivery.

The physiological dysfunctions described above are best tended to by aggressively controlling blood pressure. With restoration of acceptable blood pressures, generally in the range of 140 to 150 mm Hg systolic and 90 to 100 mm Hg diastolic, cardiac dysfunction begins to reverse, renal function tends to improve, and the restoration of cerebral autoregulatory capability lessens (but does not eliminate) the likelihood of stroke.

Rule out other causes

The foremost goal of therapy for malignant hypertension is to restore normal blood pressure, which depends on correct diagnosis so that appropriate pharmacotherapy may be initiated. For example, clinical situations that could cause malignant hypertension include such disparate entities as acute aortic dissection, acute left ventricular failure, pheochromocytoma, monoamine oxidase inhibitor–food (tyramine) interactions, eclampsia, and acute cocaine intoxication, to name but a few.

Frequently, chronic hypertension or severe preeclampsia defines the underlying “cause” of the severe hypertension, but consideration of other diagnoses, such as uncontrolled hyperthyroidism or pheochromocytoma, should not be overlooked. For example, in pheochromocytoma blood pressures tend to be paroxysmal with wide fluctuations. In hyperthyroidism, clinical signs or symptoms would be expected to accompany the clinical picture, such as the presence of proptosis, exophthalmos, lid lag, tremor, elevated temperature, and a wide pulse pressure, to name but a few.

 

Regimens to lower BP safely

It is imperative that blood pressure be lowered in a measured and safe manner, not to exceed a drop of 25% to 30% in the first 60 minutes, and not to drop below 150/95.⁴ Medications available for blood pressure reduction are listed in the Clip-and-save chart above.⁵

Every effort must be made to not overcorrect the hypertension. Too swift or too dramatic a reduction in blood pressure can have untoward consequences for both mother and fetus, including but not limited to acute fetal distress secondary to uteroplacental underperfusion, and the possibility of maternal myocardial or cerebral infarction. For these reasons, short-acting intravenous agents are recommended to treat hypertensive emergencies, and oral or sublingual compounds are to be avoided because they are more likely to cause precipitous and erratic drops in blood pressure.⁶

Pulmonary edema is not uncommon, due to capillary leakage and myocardial dysfunction. Aggressive use of furosemide along with a rapidly acting antihypertensive drug will best allow for improvement of the clinical picture in a timely manner.

Acute management steps

Critical care facilities required. During the acute management phase, patients should be cared for in an intensive care unit (or a labor and delivery unit with critical care capabilities) under the direction of physicians skilled in managing critically ill patients. In most institutions, such management will include participation of anesthesiologists, maternalfetal medicine specialists, and nurses with critical care expertise.

Delivery considerations. During initial management, the patient should have continuous fetal heart rate monitoring. Under such extreme circumstances, it is often not possible to prolong a pregnancy that is remote from term. Delivery decisions will need to balance prematurity risks against maternal risks of continuing the pregnancy.

Hypertension is not a contraindication to glucocorticoids for accelerating lung maturation in the fetus and minimizing neonatal risk of intracranial hemorrhage and necrotizing enterocolitis.⁷ Adjusting for gestational age, neonates of preeclamptic mothers are afforded no additional maturity compared with neonates born prematurely for other reasons. Delay of delivery for 48 to 72 hours may not be possible in many cases, however. Once the patient is stabilized, delivery must be considered.

Start magnesium sulfate, continue antihypertensives

At this point, it is prudent to start magnesium sulfate to prevent eclampsia. In most cases, however, excluding a diagnosis of preeclampsia in a timely manner is nearly impossible. Under these circumstances, magnesium sulfate is recommended, in addition to continued antihypertensive medications, to maintain BP control.

Magnesium sulfate is best administered intravenously, preferably through an infusion pump apparatus. A loading dose of 4 to 6 g (I prefer 6 g) is given as a 20% solution over 15 to 20 minutes, and then a continuous infusion may be initiated at a rate that depends on the patient’s renal function. In a patient with normal renal function, a rate of 2 g per hour is appropriate, but may need to be reduced if acute renal failure ensues.

In a report of 3 recent cases, investigators found magnesium sulfate was beneficial for controlling the clinical symptoms of pheochromocytoma when conventional therapy was unsuccessful. The presenting symptoms of these nonpregnant patients included hypertensive encephalopathy (2 patients) and catecholamine-induced cardiomyopathy (1 patient).⁶

In general, however, the role of magnesium sulfate should be for preventing progression to eclampsia, and not for acute blood pressure control.

Delivery decisions

Vaginal delivery is often less hemodynamically stressful for the mother, but not always practical. Many cases are remote from term with the fetus in a nonvertex presentation, or the uterine cervix is unfavorable for induction, or a protracted attempt at labor induction may not be prudent.

Under such circumstances, cesarean delivery must be considered and may be preferable. The reasons relate to the underlying maternal condition that often includes some degree of uteroplacental insufficiency. Altered placental function, combined with extreme prematurity, often results in the fetus being unable to tolerate labor for very long, necessitating emergent cesarean under potentially less controlled circumstances. The anesthesiologist and others on the critical care team must review the optimal anesthesia technique.

In most circumstances, and in the absence of coagulopathy, regional anesthesia affords the best results. When regional anesthesia is not an option, balanced general endotracheal anesthesia with antihypertensive premedication using a short-acting agent may be the safest alternative.

Maintain postpartum vigil

With delivery of the fetus, there may be a temptation to be less rigorous in maintaining blood pressure control during the post-partum period. In patients with chronic hypertension without superimposed preeclampsia, this may be acceptable, as these patients better tolerate higher blood pressures and still maintain appropriate cerebral vascular autoregulation.

 

For women who were previously normotensive, or who had superimposed preeclampsia, more rigorous control of blood pressure is recommended, especially if they show any degree of thrombocytopenia or pulmonary edema. (See Clip & save: Stepwise drug therapy for obstetric hypertensive crisis) The rationale relates to cerebral perfusion pressures and risk of stroke in these susceptible women, if thresholds are exceeded, and to the risk of worsening pulmonary edema in the setting of increased capillary hydrostatic pressure and reduced colloid osmotic pressure.

Additionally, continuation of magnesium sulfate is recommended for patients with superimposed preeclampsia until obvious signs of disease resolution, and for a minimum of 24 hours.

The author reports no financial relationships relevant to this article.

Objective

To compare 2 interventions for growth-restricted fetuses remote from term: early delivery to preempt intrauterine hypoxia, and delayed delivery for as long as possible to gain maturity.

Results

At 2 years, the overall rate of death or severe disability was 55 (19%) of 290 immediate births and 44 (16%) of 283 delayed births. After adjustment for gestational age and umbilical-artery Doppler category, the odds ratio was 1.1, indicating a trend toward more disability with immediate delivery, and the 95% credibility interval was 0.7 to 1.8.

Expert commentary

Optimal timing of delivery in high-risk pregnancies continues to confound obstetricians and perinatologists. This randomized, controlled trial attempts to address the issue in the setting of fetal growth restriction. It involved 548 pregnant women in 13 European countries who had fetal compromise between 24 and 36 weeks of gestation. In all cases, it was uncertain whether immediate delivery was indicated. These women were randomized to immediate delivery (within 48 hours to permit steroid administration) or deferred delivery (until safe delivery could be delayed no longer because of worsening test results or the passage of time). The median interval between randomization and delivery was 0.9 days with immediate delivery and 4.9 days with delayed delivery.

Strengths lie in the trial design, 2-year follow-up of infants, blinded outcomes assessment, and statistical analysis.

Weaknesses include the trial’s multicenter nature, lack of standardization for management interventions, and probable practitioner variability in disability assessment among the 69 hospitals involved.

Unanswered questions. We are not told the degree of growth restriction of the cases enrolled, or whether any misclassification errors occurred.

Decisions regarding route of delivery and intrapartum management were left to the provider’s discretion and were not standardized; this is important because a number of intrapartum events can lead to perinatal morbidity and mortality. Unexplained antepartum fetal death occurred more frequently in the expectantly managed group; the only cases of intrapartum trauma or asphyxia occurred in that group as well.

That said, at 2 years the overall results are similar between the groups. Investigators concluded that, while obstetricians seem to be intervening at the appropriate time, early intervention may not translate into improved outcomes overall.

Absent from the dialogue is the medicolegal risk associated with what some would consider inordinate delay in delivery versus premature intervention. The former generally would have the less favorable medicolegal outcome.

Bottom line

This study fails to definitively identify the optimal intervention in high-risk pregnancies remote from term. Antenatal testing remains imprecise, and fetal demise from delayed intervention must be weighed against the risk of long-term disabilities from intervening too early.

For now, the obstetrician must rely on close fetal surveillance and gestational age as the prime drivers of delivery decisions. It is also crucial that we adequately communicate to patients the potential risks associated with the 2 strategies.

Objective

To compare 2 interventions for growth-restricted fetuses remote from term: early delivery to preempt intrauterine hypoxia, and delayed delivery for as long as possible to gain maturity.

Results

At 2 years, the overall rate of death or severe disability was 55 (19%) of 290 immediate births and 44 (16%) of 283 delayed births. After adjustment for gestational age and umbilical-artery Doppler category, the odds ratio was 1.1, indicating a trend toward more disability with immediate delivery, and the 95% credibility interval was 0.7 to 1.8.

Expert commentary

Optimal timing of delivery in high-risk pregnancies continues to confound obstetricians and perinatologists. This randomized, controlled trial attempts to address the issue in the setting of fetal growth restriction. It involved 548 pregnant women in 13 European countries who had fetal compromise between 24 and 36 weeks of gestation. In all cases, it was uncertain whether immediate delivery was indicated. These women were randomized to immediate delivery (within 48 hours to permit steroid administration) or deferred delivery (until safe delivery could be delayed no longer because of worsening test results or the passage of time). The median interval between randomization and delivery was 0.9 days with immediate delivery and 4.9 days with delayed delivery.

Strengths lie in the trial design, 2-year follow-up of infants, blinded outcomes assessment, and statistical analysis.

Weaknesses include the trial’s multicenter nature, lack of standardization for management interventions, and probable practitioner variability in disability assessment among the 69 hospitals involved.

Unanswered questions. We are not told the degree of growth restriction of the cases enrolled, or whether any misclassification errors occurred.

Decisions regarding route of delivery and intrapartum management were left to the provider’s discretion and were not standardized; this is important because a number of intrapartum events can lead to perinatal morbidity and mortality. Unexplained antepartum fetal death occurred more frequently in the expectantly managed group; the only cases of intrapartum trauma or asphyxia occurred in that group as well.

That said, at 2 years the overall results are similar between the groups. Investigators concluded that, while obstetricians seem to be intervening at the appropriate time, early intervention may not translate into improved outcomes overall.

Absent from the dialogue is the medicolegal risk associated with what some would consider inordinate delay in delivery versus premature intervention. The former generally would have the less favorable medicolegal outcome.

Bottom line

This study fails to definitively identify the optimal intervention in high-risk pregnancies remote from term. Antenatal testing remains imprecise, and fetal demise from delayed intervention must be weighed against the risk of long-term disabilities from intervening too early.

For now, the obstetrician must rely on close fetal surveillance and gestational age as the prime drivers of delivery decisions. It is also crucial that we adequately communicate to patients the potential risks associated with the 2 strategies.

Objective

To compare 2 interventions for growth-restricted fetuses remote from term: early delivery to preempt intrauterine hypoxia, and delayed delivery for as long as possible to gain maturity.

Results

At 2 years, the overall rate of death or severe disability was 55 (19%) of 290 immediate births and 44 (16%) of 283 delayed births. After adjustment for gestational age and umbilical-artery Doppler category, the odds ratio was 1.1, indicating a trend toward more disability with immediate delivery, and the 95% credibility interval was 0.7 to 1.8.

Expert commentary

Optimal timing of delivery in high-risk pregnancies continues to confound obstetricians and perinatologists. This randomized, controlled trial attempts to address the issue in the setting of fetal growth restriction. It involved 548 pregnant women in 13 European countries who had fetal compromise between 24 and 36 weeks of gestation. In all cases, it was uncertain whether immediate delivery was indicated. These women were randomized to immediate delivery (within 48 hours to permit steroid administration) or deferred delivery (until safe delivery could be delayed no longer because of worsening test results or the passage of time). The median interval between randomization and delivery was 0.9 days with immediate delivery and 4.9 days with delayed delivery.

Strengths lie in the trial design, 2-year follow-up of infants, blinded outcomes assessment, and statistical analysis.

Weaknesses include the trial’s multicenter nature, lack of standardization for management interventions, and probable practitioner variability in disability assessment among the 69 hospitals involved.

Unanswered questions. We are not told the degree of growth restriction of the cases enrolled, or whether any misclassification errors occurred.

Decisions regarding route of delivery and intrapartum management were left to the provider’s discretion and were not standardized; this is important because a number of intrapartum events can lead to perinatal morbidity and mortality. Unexplained antepartum fetal death occurred more frequently in the expectantly managed group; the only cases of intrapartum trauma or asphyxia occurred in that group as well.

That said, at 2 years the overall results are similar between the groups. Investigators concluded that, while obstetricians seem to be intervening at the appropriate time, early intervention may not translate into improved outcomes overall.

Absent from the dialogue is the medicolegal risk associated with what some would consider inordinate delay in delivery versus premature intervention. The former generally would have the less favorable medicolegal outcome.

Bottom line

This study fails to definitively identify the optimal intervention in high-risk pregnancies remote from term. Antenatal testing remains imprecise, and fetal demise from delayed intervention must be weighed against the risk of long-term disabilities from intervening too early.

For now, the obstetrician must rely on close fetal surveillance and gestational age as the prime drivers of delivery decisions. It is also crucial that we adequately communicate to patients the potential risks associated with the 2 strategies.

Systematic study has established that so-called routine episiotomy should be abandoned, and restrictive-use protocols should be developed that aim, initially, for a rate of less than 30%.^1,2 Yet episiotomy (or more correctly, perineotomy) remains perhaps the most commonly performed surgical procedure in obstetrics.³ Its rate—more than 60% of vaginal deliveries in the United States—has not declined since Thacker and Banta’s landmark 1983 review.⁴

Although a large body of evidence indicates reassessment is in order, prophylactic episiotomy is a contentious issue. Indeed, it has been controversial ever since the procedure first became “routine” in the United States, in 1920. Still, advocates and dissenters share the same goal: to prevent severe perineal tears and their potential for urinary and fecal incontinence and sexual dysfunction.

This article reviews research findings that indicate:

• Data are inadequate to recommend one method of episiotomy over another.
  
• Timing of episiotomy to shorten the second stage of labor may be less relevant in an era of decreasing forceps utilization and without evidence of improved neonatal outcomes.⁵
  
• Episiotomy, particularly midline episiotomy, remains the single greatest risk that a patient will sustain a third- or fourth-degree laceration. When such lacerations occur spontaneously, recovery is equivalent to episiotomy extension or deliberate proctoepisiotomy.
  

TABLE

Incidence of third- or fourth-degree laceration with and without episiotomy

	NO. STUDIES COMPILED	NO. PATIENTS	% WITH 3RD- OR 4TH-DEGREE LACERATION
Midline episiotomy	12	49,395	6.5
No episiotomy	13	38,961	1.4
Adapted from Thorp JM.3

Research does not support presumed indications

Episiotomy was first described in 1742 as a procedure that could assist the obstetrician in difficult vaginal deliveries.³ It was not until the work of DeLee⁶ and Pomeroy⁷ was published in 1920—coincident with deliveries beginning to move from home to hospital—that the procedure became “routine.” Still, some leaders in the field—specifically, J. Whitridge Williams of Johns Hopkins—vigorously dissented.⁸

Historically, episiotomy has been used to facilitate delivery in cases of protracted second stage, instrumented vaginal delivery, and suspected fetal compromise. However, data supporting episiotomy as a facilitating procedure are sparse, and evidence endorsing prophylactic episiotomy is largely anecdotal or descriptive.

Agreement is widespread that episiotomy is warranted under certain circumstances: Shoulder dystocia, operative vaginal delivery, and a “short” perineal body have been presumed indications. Data are inadequate to support these claims, however.

Shoulder dystocia. While it might seem to make sense to perform an episiotomy (or more likely, a proctoepisiotomy) in cases of shoulder dystocia, no data from controlled trials support this theory. Given the relative rarity of severe shoulder dystocia and the inability to conduct a truly randomized trial, physicians are left with only their clinical judgment as a guide in this circumstance.

Operative delivery. Many clinicians have advocated routine episiotomy before operative vaginal delivery, particularly with forceps. The intent is to increase the space available for delivery that has been diminished by the introduction of forceps. This rationale does not hold up as well for vacuum extraction; 1 study noted that when episiotomy is performed in cases of vacuum extraction, the likelihood of severe perineal trauma is increased.⁹

It has been reported¹⁰ that the greatest risk factor for both perineal trauma and third- or fourth-degree perineal laceration is episiotomy itself (TABLE), independent of mode of delivery (spontaneous or operative).

Short perineum. Many physicians, myself included, have performed episiotomies because they perceived that the perineum was short and that even a controlled delivery with optimal use of the Ritgen maneuver probably would not prevent a perineal laceration. That said, data on anal and flatus incontinence and postpartum sexual functioning suggest that spontaneous recovery from second-degree lacerations is no worse than recovery from midline episiotomy^11,12 and, as stated, episiotomy itself is the leading risk factor for incurring a third- or fourth-degree extension—which imposes significantly greater recovery problems.

Two recent studies^11,12 identified episiotomy as a specific, independent risk factor for fecal incontinence and delayed return of sexual activity postpartum. When matched for degree of perineal trauma, episiotomy without extension still resulted in poorer outcomes at 3 and 6 months postpartum than did spontaneous second-degree lacerations, suggesting that routine episiotomy not only fails to prevent, but may actually increase risk of perineal injury and impaired function.

 

‘Prophylactic’ episiotomy is not preventive

Much debate has centered on optimal utilization of so-called prophylactic episiotomy. The intent of routine prophylactic episiotomy is to protect the pelvic floor, thus minimizing the risk of urinary incontinence and pelvic floor dysfunction. Data have suggested that absence of labor and cesarean delivery may protect against pelvic floor dysfunction; however, the role of episiotomy in preventing such dysfunction remains to be determined.

Cochrane Database review. This review¹ found no differences in vaginal or perineal trauma, dyspareunia, or urinary incontinence between patients with and without episiotomy. Patients who had an episiotomy had less risk of anterior perineal trauma but an overall greater risk of posterior perineal trauma and other complications. The reviewers concluded that restrictive episiotomy utilization is preferable to routine utilization.

The reviewers selected a total of 6 randomized trials; these examined:

• restrictive versus routine use of episiotomy;
  
• restrictive versus mediolateral episiotomy;
  
• restrictive versus routine midline episiotomy; and
  
• midline versus mediolateral episiotomy.
  

In the routine episiotomy group, 72.7% (1,752 of 2,409) of women underwent the procedure, versus 27.6% (673 of 2,441) in the restrictive episiotomy group.

Compared with routine use, restrictive episiotomy involved less posterior perineal trauma (relative risk [RR], 0.88; 95% confidence interval [CI], 0.84 to 0.920), less suturing (RR, 0.74; 95% CI, 0.71 to 0.77), and fewer healing complications (RR, 0.69; 95% CI, 0.56 to 0.85). Restrictive episiotomy was associated with more anterior perineal trauma (RR, 1.79; 95% CI, 1.55 to 2.07).

There was no difference in severe vaginal or perineal trauma (RR, 1.11; 95% CI, 0.83 to 1.50), dyspareunia (RR, 1.02; 95% CI, 0.90 to 1.16), urinary incontinence (RR 0.98; 95% CI, 0.79 to 1.20), or several pain measures.

Results for restrictive versus routine mediolateral and midline episiotomies were similar to the overall comparison.

Reviewers concluded that a policy of restrictive episiotomy appears to have several benefits over routine episiotomy: less posterior perineal trauma, less suturing, fewer complications, and no difference for most pain measures and severe vaginal or perineal trauma.

Risk of anterior perineal trauma with restrictive episiotomy was increased, however. Restrictive-use protocols, likely to be institution-specific, essentially curb episiotomy use by stating that the procedure should not be “routinely performed.” Instead, episiotomy is restricted to cases in which the clinician believes it is warranted. Examples of such situations include use of forceps, shoulder dystocia, and an estimated fetal weight above 4,000 g. As discussed, the data cannot support the value of episiotomy use even in these circumstances; however, simply discouraging routine episiotomy would effectively lower the rate to the desired 30% range.

Midline versus mediolateral incision. The most vocal debates focus on which type of episiotomy to perform and whether it should be performed earlier or later in the second stage of labor.

It has been proposed that by abandoning midline episiotomies in favor of the mediolateral technique, physicians can avoid injury to the sphincter and improve immediate birth outcome without compromising long-term function—though pros and cons of this approach are a subject of debate (see “Comparison of mid-line versus mediolateral episiotomy”).

Still, the data suggest that, when properly performed, median and mediolateral episiotomy have equivalent rates of satisfactory recovery,¹³ though the latter technique may require more technical skill for both its performance and repair.

Early versus late incision. Proponents argue that an episiotomy at the time the presenting part is crowning is “too little, too late.” They maintain that for the procedure to be truly protective, it should be utilized earlier in the second stage of labor.

Data are insufficient to confirm or refute the efficacy of early episiotomy. One would do well to remember, however, that early episiotomy was endorsed as a method to help shorten the second stage of labor when used in conjunction with prophylactic forceps delivery—a method that is now less prevalent in obstetric practice.

 

Does vaginal birth trauma cause pelvic floor dysfunction?

The relationship between vaginal birth trauma, irrespective of episiotomy, and pelvic floor dysfunction remains a topic of investigation. A recent report generated much interest in the potentially protective role of prophylactic cesarean section, particularly if performed prior to the onset of labor.¹⁴

Dr. Repke reports no financial relationship with any companies whose products are mentioned in this article.

Systematic study has established that so-called routine episiotomy should be abandoned, and restrictive-use protocols should be developed that aim, initially, for a rate of less than 30%.^1,2 Yet episiotomy (or more correctly, perineotomy) remains perhaps the most commonly performed surgical procedure in obstetrics.³ Its rate—more than 60% of vaginal deliveries in the United States—has not declined since Thacker and Banta’s landmark 1983 review.⁴

Although a large body of evidence indicates reassessment is in order, prophylactic episiotomy is a contentious issue. Indeed, it has been controversial ever since the procedure first became “routine” in the United States, in 1920. Still, advocates and dissenters share the same goal: to prevent severe perineal tears and their potential for urinary and fecal incontinence and sexual dysfunction.

This article reviews research findings that indicate:

• Data are inadequate to recommend one method of episiotomy over another.
  
• Timing of episiotomy to shorten the second stage of labor may be less relevant in an era of decreasing forceps utilization and without evidence of improved neonatal outcomes.⁵
  
• Episiotomy, particularly midline episiotomy, remains the single greatest risk that a patient will sustain a third- or fourth-degree laceration. When such lacerations occur spontaneously, recovery is equivalent to episiotomy extension or deliberate proctoepisiotomy.
  

TABLE

Incidence of third- or fourth-degree laceration with and without episiotomy

	NO. STUDIES COMPILED	NO. PATIENTS	% WITH 3RD- OR 4TH-DEGREE LACERATION
Midline episiotomy	12	49,395	6.5
No episiotomy	13	38,961	1.4
Adapted from Thorp JM.3

Research does not support presumed indications

Episiotomy was first described in 1742 as a procedure that could assist the obstetrician in difficult vaginal deliveries.³ It was not until the work of DeLee⁶ and Pomeroy⁷ was published in 1920—coincident with deliveries beginning to move from home to hospital—that the procedure became “routine.” Still, some leaders in the field—specifically, J. Whitridge Williams of Johns Hopkins—vigorously dissented.⁸

Historically, episiotomy has been used to facilitate delivery in cases of protracted second stage, instrumented vaginal delivery, and suspected fetal compromise. However, data supporting episiotomy as a facilitating procedure are sparse, and evidence endorsing prophylactic episiotomy is largely anecdotal or descriptive.

Agreement is widespread that episiotomy is warranted under certain circumstances: Shoulder dystocia, operative vaginal delivery, and a “short” perineal body have been presumed indications. Data are inadequate to support these claims, however.

Shoulder dystocia. While it might seem to make sense to perform an episiotomy (or more likely, a proctoepisiotomy) in cases of shoulder dystocia, no data from controlled trials support this theory. Given the relative rarity of severe shoulder dystocia and the inability to conduct a truly randomized trial, physicians are left with only their clinical judgment as a guide in this circumstance.

Operative delivery. Many clinicians have advocated routine episiotomy before operative vaginal delivery, particularly with forceps. The intent is to increase the space available for delivery that has been diminished by the introduction of forceps. This rationale does not hold up as well for vacuum extraction; 1 study noted that when episiotomy is performed in cases of vacuum extraction, the likelihood of severe perineal trauma is increased.⁹

It has been reported¹⁰ that the greatest risk factor for both perineal trauma and third- or fourth-degree perineal laceration is episiotomy itself (TABLE), independent of mode of delivery (spontaneous or operative).

Short perineum. Many physicians, myself included, have performed episiotomies because they perceived that the perineum was short and that even a controlled delivery with optimal use of the Ritgen maneuver probably would not prevent a perineal laceration. That said, data on anal and flatus incontinence and postpartum sexual functioning suggest that spontaneous recovery from second-degree lacerations is no worse than recovery from midline episiotomy^11,12 and, as stated, episiotomy itself is the leading risk factor for incurring a third- or fourth-degree extension—which imposes significantly greater recovery problems.

Two recent studies^11,12 identified episiotomy as a specific, independent risk factor for fecal incontinence and delayed return of sexual activity postpartum. When matched for degree of perineal trauma, episiotomy without extension still resulted in poorer outcomes at 3 and 6 months postpartum than did spontaneous second-degree lacerations, suggesting that routine episiotomy not only fails to prevent, but may actually increase risk of perineal injury and impaired function.

 

‘Prophylactic’ episiotomy is not preventive

Much debate has centered on optimal utilization of so-called prophylactic episiotomy. The intent of routine prophylactic episiotomy is to protect the pelvic floor, thus minimizing the risk of urinary incontinence and pelvic floor dysfunction. Data have suggested that absence of labor and cesarean delivery may protect against pelvic floor dysfunction; however, the role of episiotomy in preventing such dysfunction remains to be determined.

Cochrane Database review. This review¹ found no differences in vaginal or perineal trauma, dyspareunia, or urinary incontinence between patients with and without episiotomy. Patients who had an episiotomy had less risk of anterior perineal trauma but an overall greater risk of posterior perineal trauma and other complications. The reviewers concluded that restrictive episiotomy utilization is preferable to routine utilization.

The reviewers selected a total of 6 randomized trials; these examined:

• restrictive versus routine use of episiotomy;
  
• restrictive versus mediolateral episiotomy;
  
• restrictive versus routine midline episiotomy; and
  
• midline versus mediolateral episiotomy.
  

In the routine episiotomy group, 72.7% (1,752 of 2,409) of women underwent the procedure, versus 27.6% (673 of 2,441) in the restrictive episiotomy group.

Compared with routine use, restrictive episiotomy involved less posterior perineal trauma (relative risk [RR], 0.88; 95% confidence interval [CI], 0.84 to 0.920), less suturing (RR, 0.74; 95% CI, 0.71 to 0.77), and fewer healing complications (RR, 0.69; 95% CI, 0.56 to 0.85). Restrictive episiotomy was associated with more anterior perineal trauma (RR, 1.79; 95% CI, 1.55 to 2.07).

There was no difference in severe vaginal or perineal trauma (RR, 1.11; 95% CI, 0.83 to 1.50), dyspareunia (RR, 1.02; 95% CI, 0.90 to 1.16), urinary incontinence (RR 0.98; 95% CI, 0.79 to 1.20), or several pain measures.

Results for restrictive versus routine mediolateral and midline episiotomies were similar to the overall comparison.

Reviewers concluded that a policy of restrictive episiotomy appears to have several benefits over routine episiotomy: less posterior perineal trauma, less suturing, fewer complications, and no difference for most pain measures and severe vaginal or perineal trauma.

Risk of anterior perineal trauma with restrictive episiotomy was increased, however. Restrictive-use protocols, likely to be institution-specific, essentially curb episiotomy use by stating that the procedure should not be “routinely performed.” Instead, episiotomy is restricted to cases in which the clinician believes it is warranted. Examples of such situations include use of forceps, shoulder dystocia, and an estimated fetal weight above 4,000 g. As discussed, the data cannot support the value of episiotomy use even in these circumstances; however, simply discouraging routine episiotomy would effectively lower the rate to the desired 30% range.

Midline versus mediolateral incision. The most vocal debates focus on which type of episiotomy to perform and whether it should be performed earlier or later in the second stage of labor.

It has been proposed that by abandoning midline episiotomies in favor of the mediolateral technique, physicians can avoid injury to the sphincter and improve immediate birth outcome without compromising long-term function—though pros and cons of this approach are a subject of debate (see “Comparison of mid-line versus mediolateral episiotomy”).

Still, the data suggest that, when properly performed, median and mediolateral episiotomy have equivalent rates of satisfactory recovery,¹³ though the latter technique may require more technical skill for both its performance and repair.

Early versus late incision. Proponents argue that an episiotomy at the time the presenting part is crowning is “too little, too late.” They maintain that for the procedure to be truly protective, it should be utilized earlier in the second stage of labor.

Data are insufficient to confirm or refute the efficacy of early episiotomy. One would do well to remember, however, that early episiotomy was endorsed as a method to help shorten the second stage of labor when used in conjunction with prophylactic forceps delivery—a method that is now less prevalent in obstetric practice.

 

Does vaginal birth trauma cause pelvic floor dysfunction?

The relationship between vaginal birth trauma, irrespective of episiotomy, and pelvic floor dysfunction remains a topic of investigation. A recent report generated much interest in the potentially protective role of prophylactic cesarean section, particularly if performed prior to the onset of labor.¹⁴

Dr. Repke reports no financial relationship with any companies whose products are mentioned in this article.

Systematic study has established that so-called routine episiotomy should be abandoned, and restrictive-use protocols should be developed that aim, initially, for a rate of less than 30%.^1,2 Yet episiotomy (or more correctly, perineotomy) remains perhaps the most commonly performed surgical procedure in obstetrics.³ Its rate—more than 60% of vaginal deliveries in the United States—has not declined since Thacker and Banta’s landmark 1983 review.⁴

Although a large body of evidence indicates reassessment is in order, prophylactic episiotomy is a contentious issue. Indeed, it has been controversial ever since the procedure first became “routine” in the United States, in 1920. Still, advocates and dissenters share the same goal: to prevent severe perineal tears and their potential for urinary and fecal incontinence and sexual dysfunction.

This article reviews research findings that indicate:

• Data are inadequate to recommend one method of episiotomy over another.
  
• Timing of episiotomy to shorten the second stage of labor may be less relevant in an era of decreasing forceps utilization and without evidence of improved neonatal outcomes.⁵
  
• Episiotomy, particularly midline episiotomy, remains the single greatest risk that a patient will sustain a third- or fourth-degree laceration. When such lacerations occur spontaneously, recovery is equivalent to episiotomy extension or deliberate proctoepisiotomy.
  

TABLE

Incidence of third- or fourth-degree laceration with and without episiotomy

	NO. STUDIES COMPILED	NO. PATIENTS	% WITH 3RD- OR 4TH-DEGREE LACERATION
Midline episiotomy	12	49,395	6.5
No episiotomy	13	38,961	1.4
Adapted from Thorp JM.3

Research does not support presumed indications

Episiotomy was first described in 1742 as a procedure that could assist the obstetrician in difficult vaginal deliveries.³ It was not until the work of DeLee⁶ and Pomeroy⁷ was published in 1920—coincident with deliveries beginning to move from home to hospital—that the procedure became “routine.” Still, some leaders in the field—specifically, J. Whitridge Williams of Johns Hopkins—vigorously dissented.⁸

Historically, episiotomy has been used to facilitate delivery in cases of protracted second stage, instrumented vaginal delivery, and suspected fetal compromise. However, data supporting episiotomy as a facilitating procedure are sparse, and evidence endorsing prophylactic episiotomy is largely anecdotal or descriptive.

Agreement is widespread that episiotomy is warranted under certain circumstances: Shoulder dystocia, operative vaginal delivery, and a “short” perineal body have been presumed indications. Data are inadequate to support these claims, however.

Shoulder dystocia. While it might seem to make sense to perform an episiotomy (or more likely, a proctoepisiotomy) in cases of shoulder dystocia, no data from controlled trials support this theory. Given the relative rarity of severe shoulder dystocia and the inability to conduct a truly randomized trial, physicians are left with only their clinical judgment as a guide in this circumstance.

Operative delivery. Many clinicians have advocated routine episiotomy before operative vaginal delivery, particularly with forceps. The intent is to increase the space available for delivery that has been diminished by the introduction of forceps. This rationale does not hold up as well for vacuum extraction; 1 study noted that when episiotomy is performed in cases of vacuum extraction, the likelihood of severe perineal trauma is increased.⁹

It has been reported¹⁰ that the greatest risk factor for both perineal trauma and third- or fourth-degree perineal laceration is episiotomy itself (TABLE), independent of mode of delivery (spontaneous or operative).

Short perineum. Many physicians, myself included, have performed episiotomies because they perceived that the perineum was short and that even a controlled delivery with optimal use of the Ritgen maneuver probably would not prevent a perineal laceration. That said, data on anal and flatus incontinence and postpartum sexual functioning suggest that spontaneous recovery from second-degree lacerations is no worse than recovery from midline episiotomy^11,12 and, as stated, episiotomy itself is the leading risk factor for incurring a third- or fourth-degree extension—which imposes significantly greater recovery problems.

Two recent studies^11,12 identified episiotomy as a specific, independent risk factor for fecal incontinence and delayed return of sexual activity postpartum. When matched for degree of perineal trauma, episiotomy without extension still resulted in poorer outcomes at 3 and 6 months postpartum than did spontaneous second-degree lacerations, suggesting that routine episiotomy not only fails to prevent, but may actually increase risk of perineal injury and impaired function.

 

‘Prophylactic’ episiotomy is not preventive

Much debate has centered on optimal utilization of so-called prophylactic episiotomy. The intent of routine prophylactic episiotomy is to protect the pelvic floor, thus minimizing the risk of urinary incontinence and pelvic floor dysfunction. Data have suggested that absence of labor and cesarean delivery may protect against pelvic floor dysfunction; however, the role of episiotomy in preventing such dysfunction remains to be determined.

Cochrane Database review. This review¹ found no differences in vaginal or perineal trauma, dyspareunia, or urinary incontinence between patients with and without episiotomy. Patients who had an episiotomy had less risk of anterior perineal trauma but an overall greater risk of posterior perineal trauma and other complications. The reviewers concluded that restrictive episiotomy utilization is preferable to routine utilization.

The reviewers selected a total of 6 randomized trials; these examined:

• restrictive versus routine use of episiotomy;
  
• restrictive versus mediolateral episiotomy;
  
• restrictive versus routine midline episiotomy; and
  
• midline versus mediolateral episiotomy.
  

In the routine episiotomy group, 72.7% (1,752 of 2,409) of women underwent the procedure, versus 27.6% (673 of 2,441) in the restrictive episiotomy group.

Compared with routine use, restrictive episiotomy involved less posterior perineal trauma (relative risk [RR], 0.88; 95% confidence interval [CI], 0.84 to 0.920), less suturing (RR, 0.74; 95% CI, 0.71 to 0.77), and fewer healing complications (RR, 0.69; 95% CI, 0.56 to 0.85). Restrictive episiotomy was associated with more anterior perineal trauma (RR, 1.79; 95% CI, 1.55 to 2.07).

There was no difference in severe vaginal or perineal trauma (RR, 1.11; 95% CI, 0.83 to 1.50), dyspareunia (RR, 1.02; 95% CI, 0.90 to 1.16), urinary incontinence (RR 0.98; 95% CI, 0.79 to 1.20), or several pain measures.

Results for restrictive versus routine mediolateral and midline episiotomies were similar to the overall comparison.

Reviewers concluded that a policy of restrictive episiotomy appears to have several benefits over routine episiotomy: less posterior perineal trauma, less suturing, fewer complications, and no difference for most pain measures and severe vaginal or perineal trauma.

Risk of anterior perineal trauma with restrictive episiotomy was increased, however. Restrictive-use protocols, likely to be institution-specific, essentially curb episiotomy use by stating that the procedure should not be “routinely performed.” Instead, episiotomy is restricted to cases in which the clinician believes it is warranted. Examples of such situations include use of forceps, shoulder dystocia, and an estimated fetal weight above 4,000 g. As discussed, the data cannot support the value of episiotomy use even in these circumstances; however, simply discouraging routine episiotomy would effectively lower the rate to the desired 30% range.

Midline versus mediolateral incision. The most vocal debates focus on which type of episiotomy to perform and whether it should be performed earlier or later in the second stage of labor.

It has been proposed that by abandoning midline episiotomies in favor of the mediolateral technique, physicians can avoid injury to the sphincter and improve immediate birth outcome without compromising long-term function—though pros and cons of this approach are a subject of debate (see “Comparison of mid-line versus mediolateral episiotomy”).

Still, the data suggest that, when properly performed, median and mediolateral episiotomy have equivalent rates of satisfactory recovery,¹³ though the latter technique may require more technical skill for both its performance and repair.

Early versus late incision. Proponents argue that an episiotomy at the time the presenting part is crowning is “too little, too late.” They maintain that for the procedure to be truly protective, it should be utilized earlier in the second stage of labor.

Data are insufficient to confirm or refute the efficacy of early episiotomy. One would do well to remember, however, that early episiotomy was endorsed as a method to help shorten the second stage of labor when used in conjunction with prophylactic forceps delivery—a method that is now less prevalent in obstetric practice.

 

Does vaginal birth trauma cause pelvic floor dysfunction?

The relationship between vaginal birth trauma, irrespective of episiotomy, and pelvic floor dysfunction remains a topic of investigation. A recent report generated much interest in the potentially protective role of prophylactic cesarean section, particularly if performed prior to the onset of labor.¹⁴

Dr. Repke reports no financial relationship with any companies whose products are mentioned in this article.

Although it has become the basic management tool for cervical incompetence, cervical cerclage—especially emergent cerclage—remains a procedure with well-defined risks and questionable benefits. Thus, it should be used judiciously.

This article addresses 10 particularly controversial questions about this intervention.

Indications

The only generally accepted indication for elective cerclage placement is a history suggestive of cervical incompetence. For emergent cerclage, the primary indication is premature effacement or dilatation of the cervix in the absence of labor prior to 28 weeks’ gestation. Asymptomatic women with a history of midtrimester delivery and sonographic evidence of cervical shortening or funneling also may benefit from emergent cerclage placement.

Contraindications

Absolute contraindications to cervical cerclage include uterine contractions or labor, unexplained vaginal bleeding, intrauterine or vaginal infection, rupture of fetal membranes, intrauterine fetal demise, major fetal anomaly, and a gestational age beyond 28 weeks.

Factors such as placenta previa, a mucopurulent cervical discharge with membrane opacification, fetal membranes prolapsing through the cervical os, and intrauterine fetal growth restriction may be regarded as relative contraindications to emergent cerclage.

Controversy 1

What is the role of antibiotics, tocolytics, and progestins?

Antibiotics. Disagreement remains over the advisability of administering antibiotics at the time of prophylactic cerclage placement, which is generally 10 to 15 weeks’ gestation. Unfortunately, we lack sufficient data to refute or support this strategy. Because cultures do not always identify potentially pathogenic organisms, and because some “normal” flora can become pathogenic under some circumstances, my practice is to administer a prophylactic antibiotic 30 minutes prior to the procedure. Since there is no “correct” choice of antibiotic, reasonably broad-spectrum coverage is generally desirable. Cefazolin, ampicillin, erythromycin, and clindamycin all are appropriate selections for this purpose.

Because the risk of infection is greater in emergent cerclage, given the greater exposure of the membranes to vaginal flora, my practice is to administer prophylactic antibiotics during the perioperative period. If the emergent cerclage is placed close to the limits of fetal viability, I give combined antibiotic therapy. Again, however, we lack sufficient data to definitively justify this approach. The risks and benefits must be discussed with the patient and her family, with all parties agreeing on the appropriate course.

Tocolytic therapy is a bit less controversial in regard to prophylactic cerclage. At 10 to 15 weeks’ gestation, preterm labor is unlikely. Thus, tocolytics are not called for, though sometimes they are given perioperatively to reduce cramping. As with the antibiotics controversy, data are insufficient to support or condemn this practice.

One or 2 doses of indomethacin at the time of cerclage placement has been anecdotally reported to reduce cramping and, potentially, local inflammatory response; again, evidence is lacking. The risks of such an approach are negligible. Nevertheless, they should be reviewed with the patient, along with benefits.

Prophylactic tocolytic therapy may be employed in the setting of emergent cerclage, especially if the procedure is performed at the limits of fetal viability when corticosteroid administration is being considered. Whether this approach prolongs pregnancy or improves outcomes is unclear.

Progestins have enjoyed episodic popularity as a means of reducing preterm birth. For this reason, clinicians have given progesterone as an adjunct to cerclage placement, either as an ongoing or perioperative regimen. The data that do exist suggest that the role of progestins—if there is one—may be to deter preterm labor rather than to reduce cervical incompetence. Therefore, progestins should not be used therapeutically as an acute intervention. For these reasons, progestins are not routinely given as an adjunct to cerclage.

In selected patients, transabdominal cervicoisthmic cerclage safely reduces the incidence of second-trimester pregnancy loss due to cervical incompetence.

Controversy 2

When is transabdominal cerclage an option?

Transabdominal cervicoisthmic cerclage (TAC) was developed for patients in whom placement of a transvaginal cerclage was technically impossible or in whom a prior cerclage had been unsuccessful. It was first described by Benson and Durfee, who published the results of their initial 10 cases in 1965.¹ The perinatal salvage rate in this series was 11% (5 viable infants out of 45 pregnancies) before and 82% (11 of 13) after TAC placement.¹

 

Since that series, a number of investigators have used TAC in selected patients with cervical incompetence, and have reported similar results.^2-4 These data suggest that, in selected patients, TAC is safe and effective at reducing the incidence of second-trimester pregnancy loss due to cervical incompetence.

There is no evidence, however, that TAC is superior to transvaginal cerclage as an initial procedure in the management of cervical incompetence. Furthermore, TAC is associated with far more morbidity than transvaginal cerclage. Not only does it require a laparotomy for placement, but subsequent cesarean delivery is necessary. For these reasons, TAC should be reserved for patients with documented cervical incompetence who have either failed previous transvaginal cerclage or in whom a transvaginal cerclage is technically impossible to place, e.g., when there is little of the anatomic cervix to work with.

Multiple cervical therapies for dysplasia, prior Manchester-Fothergill operation, or severe adenosis secondary to diethylstilbestrol (DES) exposure are other examples of situations in which the transvaginal approach to cerclage may be impossible.

Controversy 3

After placement, what follow-up is necessary?

Many approaches have been employed in the prophylactic-cerclage patient, all of them unencumbered by data. Empirically, many patients benefit from the freedom to carry on routine activities until 16 weeks’ gestation, at which time various restrictions are imposed, depending on the risk of preterm delivery.

The most frequently employed follow-up today is the ultrasound examination to assess cervical length, although its superiority to digital examination is not well-substantiated. Nevertheless, a cervical length that appears to be normal on ultrasound is very reassuring for the patient, and the benefit of such reassurance is difficult to quantify—but probably real.

After 24 weeks’ gestation, the need for follow-up of the cervix diminishes, since further surgical intervention would be unlikely. After this gestational age, surveillance will be mainly for preterm labor. Because it often is difficult to distinguish cervical incompetence from preterm labor, close surveillance for the latter is prudent and justified.

When it comes to emergent cerclage, patients initially tend to be hospitalized. Since the underlying problem necessitating the cerclage (infection, incompetence, concealed abruption) is rarely clear, the need for caution is greater. These patients generally benefit from close ultrasound surveillance and, as gestation progresses, close surveillance for preterm labor. Additional restrictions such as bed rest generally are imposed as well, but we lack data proving that they improve pregnancy outcome.

Retention of the cerclage may prolong latency, allowing for a more favorable gestational age at delivery. On the other hand, it also may provide a nidus for infection.

Controversy 4

What is the optimal time for removal?

Since the purpose of cerclage placement is to prevent prematurity, I generally recommend delaying removal until 37 weeks’ gestation, when the definition of “term” is met. There is no standard of care attached to this gestational age, and removal at 36 or 38 weeks is perfectly acceptable.

Too-early removal should be avoided, as this increases the possibility of a significantly premature delivery. It also is inadvisable to delay removal beyond 38 weeks, when the benefits of prolonging gestation are negligible and the risk of cervical damage with initiation of labor closer to term is increased.

Of course, if increased uterine activity at an earlier gestational age places the cerclage under tension, earlier removal is justified.

Controversy 5

Should the cerclage be removed if the membranes rupture?

The presence of a cerclage does not appear to increase the incidence of preterm premature rupture of membranes (PROM) remote from placement. On occasion, however, preterm rupture occurs with a cerclage in place. Retention of the cerclage may prolong latency, allowing for a more favorable gestational age at delivery. On the other hand, a retained cerclage may provide a nidus for infection.

Ludmir et al⁵ conducted a retrospective analysis of prophylactic McDonald cerclage in 30 singleton pregnancies complicated by preterm PROM between 24 and 32 weeks’ gestation. In 20 cases (67%), the cerclage was removed at presentation at the discretion of the attending obstetrician; in the remaining 10 cases (33%), the cerclage was retained until delivery. The difference in likelihood of delivery within 24 hours of presentation between the 2 groups was significant: 30% (6 of 20) in the removed versus 0% (0 of 10) in the retained group. The neonatal mortality rate in the retained group was 70% (7 of 10), however, compared with 10% (2 of 20) in the removed group (P<.001 seventy-one percent of neonatal deaths in the retained group were result early sepsis compared with removed>P<.001 neonatal mortality was not examined by gestational age.>

A more recent retrospective analysis of pregnancy outcomes in 81 patients with preterm PROM and preexisting cerclage between 24 and 35 weeks’ gestation suggested that the decision to remove or retain the cerclage had no effect on latency or perinatal outcome.⁶ Comparison of the cerclage patients with 162 control subjects with preterm PROM but no cerclage suggested that gestational age at presentation was the most important determinant of pregnancy outcome.⁶

 

In light of these data, Ob/Gyns should individualize the management of patients with preterm PROM and a preexisting cerclage, weighing the risk of infection against those of precipitating an extremely premature delivery with cerclage removal.

In my own practice, I have changed from being a staunch advocate of cerclage removal to a supporter of either approach, depending on individual practice style (my style remaining one of removal in the setting of preterm PROM, provided that such removal can be easily accomplished).

It is unlikely that a patient with a short cervix and no history of adverse pregnancy outcome would benefit from cerclage.

Again, we are hampered in decision-making by a paucity of data to support or refute either approach. I would emphasize the importance of dialogue, making sure the patient is aware of her options before a course of action is decided upon.

Controversy 6

Should a cerclage be placed in a woman with a short cervix?

In recent years, a number of screening tests have been introduced to identify women at increased risk of preterm delivery: biochemical tests such as fetal fibronectin,^7,8 hormonal tests such as salivary estriol,⁹ and serial cervical ultrasound examinations to assess cervical length and the presence or absence of membrane funneling.^10,11 Real-time sonographic evaluation of the cervix has demonstrated a strong inverse correlation between cervical length and preterm delivery.^10,11 If the cervical length is below the 10th percentile for gestational age, the pregnancy is at a 6-fold increased risk of delivery prior to 35 weeks.¹⁰ A cervical length of 15 mm or less at 23 weeks occurs in less than 2% of low-risk women, but is predictive of delivery prior to 28 weeks and 32 weeks in 60% and 90% of cases, respectively.¹⁰

Several retrospective studies suggest that placement of a cervical cerclage in asymptomatic women with short cervical length may improve perinatal outcome.^12-15 One study reported a 10-fold reduction in the incidence of delivery prior to 32 weeks’ gestation in women treated with cerclage, with pretermdelivery rates of 52% and 5% for women in the control and cerclage groups, respectively.¹³ These women were identified via endovaginal ultrasound as having a reduced cervical length prior to 24 weeks’ gestation.

According to more recent data, however, cerclage is not indicated in women with evidence of cervical shortening.^16,17 Indeed, 1 study showed a higher rate of preterm PROM in women undergoing cerclage, compared with those without cerclage (65.2% versus 36.5%; P<.05>17 Further studies are needed.

In essence, clinicians must tabulate all of the risks for preterm birth before selecting a course of action, with the final decision residing in a risk-benefit analysis that involves the patient. For example, it is unlikely that a patient with a short cervix (found incidentally on ultrasound) and no history of adverse pregnancy outcome would benefit from cerclage. She may, however, benefit from other screening modalities, such as ultrasound surveillance of cervical length until 24 weeks, and possibly fetal fibronectin determinations to better assess her absence of risk for preterm delivery.

On the other hand, a patient with a history of prior idiopathic preterm delivery who is found via ultrasound to have a shortened cervix may benefit from early cerclage placement.

Controversy 7

Should all DES-exposed women be offered prophylactic cerclage?

In utero exposure to DES alters the structure of the cervix in up to 69% of women.¹⁸ For example, the endocervical canal is narrower, and the demarcation between it and the lower uterine segment is less clear than in unexposed women. In addition, the cervix does not protrude as far into the vagina as in unexposed women. These and other changes can resemble alterations associated with an incompetent cervix.

Women exposed to DES are 2.6 to 6.7 times more likely than unexposed women to experience premature delivery.¹⁸ Even so, most experts have concluded that prophylactic cerclage is not indicated in patients with a history of in utero exposure to DES unless those women have experienced a previous pregnancy loss or have clear evidence of cervical shortening. One reason is the fact that the DES-exposed cervix responds differently to surgery. Further studies are required to clarify this issue.

Controversy 8

What is the role of cervical cerclage in multiple gestations?

Although multiple gestations face an increased risk of preterm delivery, there is no reliable evidence that prophylactic cerclage is helpful in uncomplicated twin pregnancies.^19-22 In fact, a randomized trial of the issue failed to reveal any advantage,²⁰ as did 2 randomized trials involving women at high risk of preterm delivery that included patients with twins.^21,22 (Women with a classic history of cervical incompetence were excluded from the latter trial.)²²

 

Because the data do not clearly support the use of cervical cerclage in higher-order multiple gestations, it is not recommended at this time. However, it appears that prophylactic cerclage may reduce extremely premature births in triplet pregnancies.²³

Complications such as infection and erosion of the cerclage into adjacent organs suggest that the cerclage should be removed once its function has been fulfilled.

Controversy 9

Should a cerclage be placed prior to pregnancy?

Cerclage placement prior to pregnancy is predicated on the assumption that avoiding manipulation of the cervix during pregnancy is desirable. This is particularly true in circumstances when the more elaborate cerclage procedures are necessary, such as abdominal or Shirodkar techniques. With these modalities, blood loss may be greater during pregnancy, and cervical manipulation may be more extensive.

Data to support or condemn this approach are insufficient, but certain practical considerations are worth mentioning. The most frequently cited risk of cerclage placement during pregnancy is loss of the pregnancy. Anatomic injury to surrounding structures may occur in either the pregnant or nonpregnant state. Placement prior to pregnancy also can be problematic if subsequent pregnancy loss occurs or a fetal anomaly is diagnosed—especially in the case of abdominal cerclage. In extreme circumstances, the need for uterine evacuation via hysterotomy could arise. There is also the theoretical risk of reduced fertility due to increased inflammation of the cervix if the cerclage is placed prior to conception.

For these reasons, coupled with improved techniques of ultrasound diagnosis and obstetric anesthesia, I opt for placement of cerclage in the late first trimester of pregnancy.

CONTROVERSY 10

Is there a role for permanent cerclage placement?

By and large, permanent cerclage placement is not recommended. Complications, including infection and erosion of the cerclage into adjacent organs, suggest that the cerclage should be removed once its function has been fulfilled. The issue of permanent cerclage placement arises almost exclusively in regard to abdominal cerclage—less often to the “true” (as opposed to modified) Shirodkar cerclage. Since cesarean delivery is necessary in cases of abdominal cerclage, the cerclage may be removed when the patient experiences what she has determined will be her final delivery.

Dr. Repke reports no affiliations or financial arrangements with any of the manufacturers of products mentioned in this article or their competitors.

Although it has become the basic management tool for cervical incompetence, cervical cerclage—especially emergent cerclage—remains a procedure with well-defined risks and questionable benefits. Thus, it should be used judiciously.

This article addresses 10 particularly controversial questions about this intervention.

Indications

The only generally accepted indication for elective cerclage placement is a history suggestive of cervical incompetence. For emergent cerclage, the primary indication is premature effacement or dilatation of the cervix in the absence of labor prior to 28 weeks’ gestation. Asymptomatic women with a history of midtrimester delivery and sonographic evidence of cervical shortening or funneling also may benefit from emergent cerclage placement.

Contraindications

Absolute contraindications to cervical cerclage include uterine contractions or labor, unexplained vaginal bleeding, intrauterine or vaginal infection, rupture of fetal membranes, intrauterine fetal demise, major fetal anomaly, and a gestational age beyond 28 weeks.

Factors such as placenta previa, a mucopurulent cervical discharge with membrane opacification, fetal membranes prolapsing through the cervical os, and intrauterine fetal growth restriction may be regarded as relative contraindications to emergent cerclage.

Controversy 1

What is the role of antibiotics, tocolytics, and progestins?

Antibiotics. Disagreement remains over the advisability of administering antibiotics at the time of prophylactic cerclage placement, which is generally 10 to 15 weeks’ gestation. Unfortunately, we lack sufficient data to refute or support this strategy. Because cultures do not always identify potentially pathogenic organisms, and because some “normal” flora can become pathogenic under some circumstances, my practice is to administer a prophylactic antibiotic 30 minutes prior to the procedure. Since there is no “correct” choice of antibiotic, reasonably broad-spectrum coverage is generally desirable. Cefazolin, ampicillin, erythromycin, and clindamycin all are appropriate selections for this purpose.

Because the risk of infection is greater in emergent cerclage, given the greater exposure of the membranes to vaginal flora, my practice is to administer prophylactic antibiotics during the perioperative period. If the emergent cerclage is placed close to the limits of fetal viability, I give combined antibiotic therapy. Again, however, we lack sufficient data to definitively justify this approach. The risks and benefits must be discussed with the patient and her family, with all parties agreeing on the appropriate course.

Tocolytic therapy is a bit less controversial in regard to prophylactic cerclage. At 10 to 15 weeks’ gestation, preterm labor is unlikely. Thus, tocolytics are not called for, though sometimes they are given perioperatively to reduce cramping. As with the antibiotics controversy, data are insufficient to support or condemn this practice.

One or 2 doses of indomethacin at the time of cerclage placement has been anecdotally reported to reduce cramping and, potentially, local inflammatory response; again, evidence is lacking. The risks of such an approach are negligible. Nevertheless, they should be reviewed with the patient, along with benefits.

Prophylactic tocolytic therapy may be employed in the setting of emergent cerclage, especially if the procedure is performed at the limits of fetal viability when corticosteroid administration is being considered. Whether this approach prolongs pregnancy or improves outcomes is unclear.

Progestins have enjoyed episodic popularity as a means of reducing preterm birth. For this reason, clinicians have given progesterone as an adjunct to cerclage placement, either as an ongoing or perioperative regimen. The data that do exist suggest that the role of progestins—if there is one—may be to deter preterm labor rather than to reduce cervical incompetence. Therefore, progestins should not be used therapeutically as an acute intervention. For these reasons, progestins are not routinely given as an adjunct to cerclage.

In selected patients, transabdominal cervicoisthmic cerclage safely reduces the incidence of second-trimester pregnancy loss due to cervical incompetence.

Controversy 2

When is transabdominal cerclage an option?

Transabdominal cervicoisthmic cerclage (TAC) was developed for patients in whom placement of a transvaginal cerclage was technically impossible or in whom a prior cerclage had been unsuccessful. It was first described by Benson and Durfee, who published the results of their initial 10 cases in 1965.¹ The perinatal salvage rate in this series was 11% (5 viable infants out of 45 pregnancies) before and 82% (11 of 13) after TAC placement.¹

 

Since that series, a number of investigators have used TAC in selected patients with cervical incompetence, and have reported similar results.^2-4 These data suggest that, in selected patients, TAC is safe and effective at reducing the incidence of second-trimester pregnancy loss due to cervical incompetence.

There is no evidence, however, that TAC is superior to transvaginal cerclage as an initial procedure in the management of cervical incompetence. Furthermore, TAC is associated with far more morbidity than transvaginal cerclage. Not only does it require a laparotomy for placement, but subsequent cesarean delivery is necessary. For these reasons, TAC should be reserved for patients with documented cervical incompetence who have either failed previous transvaginal cerclage or in whom a transvaginal cerclage is technically impossible to place, e.g., when there is little of the anatomic cervix to work with.

Multiple cervical therapies for dysplasia, prior Manchester-Fothergill operation, or severe adenosis secondary to diethylstilbestrol (DES) exposure are other examples of situations in which the transvaginal approach to cerclage may be impossible.

Controversy 3

After placement, what follow-up is necessary?

Many approaches have been employed in the prophylactic-cerclage patient, all of them unencumbered by data. Empirically, many patients benefit from the freedom to carry on routine activities until 16 weeks’ gestation, at which time various restrictions are imposed, depending on the risk of preterm delivery.

The most frequently employed follow-up today is the ultrasound examination to assess cervical length, although its superiority to digital examination is not well-substantiated. Nevertheless, a cervical length that appears to be normal on ultrasound is very reassuring for the patient, and the benefit of such reassurance is difficult to quantify—but probably real.

After 24 weeks’ gestation, the need for follow-up of the cervix diminishes, since further surgical intervention would be unlikely. After this gestational age, surveillance will be mainly for preterm labor. Because it often is difficult to distinguish cervical incompetence from preterm labor, close surveillance for the latter is prudent and justified.

When it comes to emergent cerclage, patients initially tend to be hospitalized. Since the underlying problem necessitating the cerclage (infection, incompetence, concealed abruption) is rarely clear, the need for caution is greater. These patients generally benefit from close ultrasound surveillance and, as gestation progresses, close surveillance for preterm labor. Additional restrictions such as bed rest generally are imposed as well, but we lack data proving that they improve pregnancy outcome.

Retention of the cerclage may prolong latency, allowing for a more favorable gestational age at delivery. On the other hand, it also may provide a nidus for infection.

Controversy 4

What is the optimal time for removal?

Since the purpose of cerclage placement is to prevent prematurity, I generally recommend delaying removal until 37 weeks’ gestation, when the definition of “term” is met. There is no standard of care attached to this gestational age, and removal at 36 or 38 weeks is perfectly acceptable.

Too-early removal should be avoided, as this increases the possibility of a significantly premature delivery. It also is inadvisable to delay removal beyond 38 weeks, when the benefits of prolonging gestation are negligible and the risk of cervical damage with initiation of labor closer to term is increased.

Of course, if increased uterine activity at an earlier gestational age places the cerclage under tension, earlier removal is justified.

Controversy 5

Should the cerclage be removed if the membranes rupture?

The presence of a cerclage does not appear to increase the incidence of preterm premature rupture of membranes (PROM) remote from placement. On occasion, however, preterm rupture occurs with a cerclage in place. Retention of the cerclage may prolong latency, allowing for a more favorable gestational age at delivery. On the other hand, a retained cerclage may provide a nidus for infection.

Ludmir et al⁵ conducted a retrospective analysis of prophylactic McDonald cerclage in 30 singleton pregnancies complicated by preterm PROM between 24 and 32 weeks’ gestation. In 20 cases (67%), the cerclage was removed at presentation at the discretion of the attending obstetrician; in the remaining 10 cases (33%), the cerclage was retained until delivery. The difference in likelihood of delivery within 24 hours of presentation between the 2 groups was significant: 30% (6 of 20) in the removed versus 0% (0 of 10) in the retained group. The neonatal mortality rate in the retained group was 70% (7 of 10), however, compared with 10% (2 of 20) in the removed group (P<.001 seventy-one percent of neonatal deaths in the retained group were result early sepsis compared with removed>P<.001 neonatal mortality was not examined by gestational age.>

A more recent retrospective analysis of pregnancy outcomes in 81 patients with preterm PROM and preexisting cerclage between 24 and 35 weeks’ gestation suggested that the decision to remove or retain the cerclage had no effect on latency or perinatal outcome.⁶ Comparison of the cerclage patients with 162 control subjects with preterm PROM but no cerclage suggested that gestational age at presentation was the most important determinant of pregnancy outcome.⁶

 

In light of these data, Ob/Gyns should individualize the management of patients with preterm PROM and a preexisting cerclage, weighing the risk of infection against those of precipitating an extremely premature delivery with cerclage removal.

In my own practice, I have changed from being a staunch advocate of cerclage removal to a supporter of either approach, depending on individual practice style (my style remaining one of removal in the setting of preterm PROM, provided that such removal can be easily accomplished).

It is unlikely that a patient with a short cervix and no history of adverse pregnancy outcome would benefit from cerclage.

Again, we are hampered in decision-making by a paucity of data to support or refute either approach. I would emphasize the importance of dialogue, making sure the patient is aware of her options before a course of action is decided upon.

Controversy 6

Should a cerclage be placed in a woman with a short cervix?

In recent years, a number of screening tests have been introduced to identify women at increased risk of preterm delivery: biochemical tests such as fetal fibronectin,^7,8 hormonal tests such as salivary estriol,⁹ and serial cervical ultrasound examinations to assess cervical length and the presence or absence of membrane funneling.^10,11 Real-time sonographic evaluation of the cervix has demonstrated a strong inverse correlation between cervical length and preterm delivery.^10,11 If the cervical length is below the 10th percentile for gestational age, the pregnancy is at a 6-fold increased risk of delivery prior to 35 weeks.¹⁰ A cervical length of 15 mm or less at 23 weeks occurs in less than 2% of low-risk women, but is predictive of delivery prior to 28 weeks and 32 weeks in 60% and 90% of cases, respectively.¹⁰

Several retrospective studies suggest that placement of a cervical cerclage in asymptomatic women with short cervical length may improve perinatal outcome.^12-15 One study reported a 10-fold reduction in the incidence of delivery prior to 32 weeks’ gestation in women treated with cerclage, with pretermdelivery rates of 52% and 5% for women in the control and cerclage groups, respectively.¹³ These women were identified via endovaginal ultrasound as having a reduced cervical length prior to 24 weeks’ gestation.

According to more recent data, however, cerclage is not indicated in women with evidence of cervical shortening.^16,17 Indeed, 1 study showed a higher rate of preterm PROM in women undergoing cerclage, compared with those without cerclage (65.2% versus 36.5%; P<.05>17 Further studies are needed.

In essence, clinicians must tabulate all of the risks for preterm birth before selecting a course of action, with the final decision residing in a risk-benefit analysis that involves the patient. For example, it is unlikely that a patient with a short cervix (found incidentally on ultrasound) and no history of adverse pregnancy outcome would benefit from cerclage. She may, however, benefit from other screening modalities, such as ultrasound surveillance of cervical length until 24 weeks, and possibly fetal fibronectin determinations to better assess her absence of risk for preterm delivery.

On the other hand, a patient with a history of prior idiopathic preterm delivery who is found via ultrasound to have a shortened cervix may benefit from early cerclage placement.

Controversy 7

Should all DES-exposed women be offered prophylactic cerclage?

In utero exposure to DES alters the structure of the cervix in up to 69% of women.¹⁸ For example, the endocervical canal is narrower, and the demarcation between it and the lower uterine segment is less clear than in unexposed women. In addition, the cervix does not protrude as far into the vagina as in unexposed women. These and other changes can resemble alterations associated with an incompetent cervix.

Women exposed to DES are 2.6 to 6.7 times more likely than unexposed women to experience premature delivery.¹⁸ Even so, most experts have concluded that prophylactic cerclage is not indicated in patients with a history of in utero exposure to DES unless those women have experienced a previous pregnancy loss or have clear evidence of cervical shortening. One reason is the fact that the DES-exposed cervix responds differently to surgery. Further studies are required to clarify this issue.

Controversy 8

What is the role of cervical cerclage in multiple gestations?

Although multiple gestations face an increased risk of preterm delivery, there is no reliable evidence that prophylactic cerclage is helpful in uncomplicated twin pregnancies.^19-22 In fact, a randomized trial of the issue failed to reveal any advantage,²⁰ as did 2 randomized trials involving women at high risk of preterm delivery that included patients with twins.^21,22 (Women with a classic history of cervical incompetence were excluded from the latter trial.)²²

 

Because the data do not clearly support the use of cervical cerclage in higher-order multiple gestations, it is not recommended at this time. However, it appears that prophylactic cerclage may reduce extremely premature births in triplet pregnancies.²³

Complications such as infection and erosion of the cerclage into adjacent organs suggest that the cerclage should be removed once its function has been fulfilled.

Controversy 9

Should a cerclage be placed prior to pregnancy?

Cerclage placement prior to pregnancy is predicated on the assumption that avoiding manipulation of the cervix during pregnancy is desirable. This is particularly true in circumstances when the more elaborate cerclage procedures are necessary, such as abdominal or Shirodkar techniques. With these modalities, blood loss may be greater during pregnancy, and cervical manipulation may be more extensive.

Data to support or condemn this approach are insufficient, but certain practical considerations are worth mentioning. The most frequently cited risk of cerclage placement during pregnancy is loss of the pregnancy. Anatomic injury to surrounding structures may occur in either the pregnant or nonpregnant state. Placement prior to pregnancy also can be problematic if subsequent pregnancy loss occurs or a fetal anomaly is diagnosed—especially in the case of abdominal cerclage. In extreme circumstances, the need for uterine evacuation via hysterotomy could arise. There is also the theoretical risk of reduced fertility due to increased inflammation of the cervix if the cerclage is placed prior to conception.

For these reasons, coupled with improved techniques of ultrasound diagnosis and obstetric anesthesia, I opt for placement of cerclage in the late first trimester of pregnancy.

CONTROVERSY 10

Is there a role for permanent cerclage placement?

By and large, permanent cerclage placement is not recommended. Complications, including infection and erosion of the cerclage into adjacent organs, suggest that the cerclage should be removed once its function has been fulfilled. The issue of permanent cerclage placement arises almost exclusively in regard to abdominal cerclage—less often to the “true” (as opposed to modified) Shirodkar cerclage. Since cesarean delivery is necessary in cases of abdominal cerclage, the cerclage may be removed when the patient experiences what she has determined will be her final delivery.

Dr. Repke reports no affiliations or financial arrangements with any of the manufacturers of products mentioned in this article or their competitors.

Although it has become the basic management tool for cervical incompetence, cervical cerclage—especially emergent cerclage—remains a procedure with well-defined risks and questionable benefits. Thus, it should be used judiciously.

This article addresses 10 particularly controversial questions about this intervention.

Indications

The only generally accepted indication for elective cerclage placement is a history suggestive of cervical incompetence. For emergent cerclage, the primary indication is premature effacement or dilatation of the cervix in the absence of labor prior to 28 weeks’ gestation. Asymptomatic women with a history of midtrimester delivery and sonographic evidence of cervical shortening or funneling also may benefit from emergent cerclage placement.

Contraindications

Absolute contraindications to cervical cerclage include uterine contractions or labor, unexplained vaginal bleeding, intrauterine or vaginal infection, rupture of fetal membranes, intrauterine fetal demise, major fetal anomaly, and a gestational age beyond 28 weeks.

Factors such as placenta previa, a mucopurulent cervical discharge with membrane opacification, fetal membranes prolapsing through the cervical os, and intrauterine fetal growth restriction may be regarded as relative contraindications to emergent cerclage.

Controversy 1

What is the role of antibiotics, tocolytics, and progestins?

Antibiotics. Disagreement remains over the advisability of administering antibiotics at the time of prophylactic cerclage placement, which is generally 10 to 15 weeks’ gestation. Unfortunately, we lack sufficient data to refute or support this strategy. Because cultures do not always identify potentially pathogenic organisms, and because some “normal” flora can become pathogenic under some circumstances, my practice is to administer a prophylactic antibiotic 30 minutes prior to the procedure. Since there is no “correct” choice of antibiotic, reasonably broad-spectrum coverage is generally desirable. Cefazolin, ampicillin, erythromycin, and clindamycin all are appropriate selections for this purpose.

Because the risk of infection is greater in emergent cerclage, given the greater exposure of the membranes to vaginal flora, my practice is to administer prophylactic antibiotics during the perioperative period. If the emergent cerclage is placed close to the limits of fetal viability, I give combined antibiotic therapy. Again, however, we lack sufficient data to definitively justify this approach. The risks and benefits must be discussed with the patient and her family, with all parties agreeing on the appropriate course.

Tocolytic therapy is a bit less controversial in regard to prophylactic cerclage. At 10 to 15 weeks’ gestation, preterm labor is unlikely. Thus, tocolytics are not called for, though sometimes they are given perioperatively to reduce cramping. As with the antibiotics controversy, data are insufficient to support or condemn this practice.

One or 2 doses of indomethacin at the time of cerclage placement has been anecdotally reported to reduce cramping and, potentially, local inflammatory response; again, evidence is lacking. The risks of such an approach are negligible. Nevertheless, they should be reviewed with the patient, along with benefits.

Prophylactic tocolytic therapy may be employed in the setting of emergent cerclage, especially if the procedure is performed at the limits of fetal viability when corticosteroid administration is being considered. Whether this approach prolongs pregnancy or improves outcomes is unclear.

Progestins have enjoyed episodic popularity as a means of reducing preterm birth. For this reason, clinicians have given progesterone as an adjunct to cerclage placement, either as an ongoing or perioperative regimen. The data that do exist suggest that the role of progestins—if there is one—may be to deter preterm labor rather than to reduce cervical incompetence. Therefore, progestins should not be used therapeutically as an acute intervention. For these reasons, progestins are not routinely given as an adjunct to cerclage.

In selected patients, transabdominal cervicoisthmic cerclage safely reduces the incidence of second-trimester pregnancy loss due to cervical incompetence.

Controversy 2

When is transabdominal cerclage an option?

Transabdominal cervicoisthmic cerclage (TAC) was developed for patients in whom placement of a transvaginal cerclage was technically impossible or in whom a prior cerclage had been unsuccessful. It was first described by Benson and Durfee, who published the results of their initial 10 cases in 1965.¹ The perinatal salvage rate in this series was 11% (5 viable infants out of 45 pregnancies) before and 82% (11 of 13) after TAC placement.¹

 

Since that series, a number of investigators have used TAC in selected patients with cervical incompetence, and have reported similar results.^2-4 These data suggest that, in selected patients, TAC is safe and effective at reducing the incidence of second-trimester pregnancy loss due to cervical incompetence.

There is no evidence, however, that TAC is superior to transvaginal cerclage as an initial procedure in the management of cervical incompetence. Furthermore, TAC is associated with far more morbidity than transvaginal cerclage. Not only does it require a laparotomy for placement, but subsequent cesarean delivery is necessary. For these reasons, TAC should be reserved for patients with documented cervical incompetence who have either failed previous transvaginal cerclage or in whom a transvaginal cerclage is technically impossible to place, e.g., when there is little of the anatomic cervix to work with.

Multiple cervical therapies for dysplasia, prior Manchester-Fothergill operation, or severe adenosis secondary to diethylstilbestrol (DES) exposure are other examples of situations in which the transvaginal approach to cerclage may be impossible.

Controversy 3

After placement, what follow-up is necessary?

Many approaches have been employed in the prophylactic-cerclage patient, all of them unencumbered by data. Empirically, many patients benefit from the freedom to carry on routine activities until 16 weeks’ gestation, at which time various restrictions are imposed, depending on the risk of preterm delivery.

The most frequently employed follow-up today is the ultrasound examination to assess cervical length, although its superiority to digital examination is not well-substantiated. Nevertheless, a cervical length that appears to be normal on ultrasound is very reassuring for the patient, and the benefit of such reassurance is difficult to quantify—but probably real.

After 24 weeks’ gestation, the need for follow-up of the cervix diminishes, since further surgical intervention would be unlikely. After this gestational age, surveillance will be mainly for preterm labor. Because it often is difficult to distinguish cervical incompetence from preterm labor, close surveillance for the latter is prudent and justified.

When it comes to emergent cerclage, patients initially tend to be hospitalized. Since the underlying problem necessitating the cerclage (infection, incompetence, concealed abruption) is rarely clear, the need for caution is greater. These patients generally benefit from close ultrasound surveillance and, as gestation progresses, close surveillance for preterm labor. Additional restrictions such as bed rest generally are imposed as well, but we lack data proving that they improve pregnancy outcome.

Retention of the cerclage may prolong latency, allowing for a more favorable gestational age at delivery. On the other hand, it also may provide a nidus for infection.

Controversy 4

What is the optimal time for removal?

Since the purpose of cerclage placement is to prevent prematurity, I generally recommend delaying removal until 37 weeks’ gestation, when the definition of “term” is met. There is no standard of care attached to this gestational age, and removal at 36 or 38 weeks is perfectly acceptable.

Too-early removal should be avoided, as this increases the possibility of a significantly premature delivery. It also is inadvisable to delay removal beyond 38 weeks, when the benefits of prolonging gestation are negligible and the risk of cervical damage with initiation of labor closer to term is increased.

Of course, if increased uterine activity at an earlier gestational age places the cerclage under tension, earlier removal is justified.

Controversy 5

Should the cerclage be removed if the membranes rupture?

The presence of a cerclage does not appear to increase the incidence of preterm premature rupture of membranes (PROM) remote from placement. On occasion, however, preterm rupture occurs with a cerclage in place. Retention of the cerclage may prolong latency, allowing for a more favorable gestational age at delivery. On the other hand, a retained cerclage may provide a nidus for infection.

Ludmir et al⁵ conducted a retrospective analysis of prophylactic McDonald cerclage in 30 singleton pregnancies complicated by preterm PROM between 24 and 32 weeks’ gestation. In 20 cases (67%), the cerclage was removed at presentation at the discretion of the attending obstetrician; in the remaining 10 cases (33%), the cerclage was retained until delivery. The difference in likelihood of delivery within 24 hours of presentation between the 2 groups was significant: 30% (6 of 20) in the removed versus 0% (0 of 10) in the retained group. The neonatal mortality rate in the retained group was 70% (7 of 10), however, compared with 10% (2 of 20) in the removed group (P<.001 seventy-one percent of neonatal deaths in the retained group were result early sepsis compared with removed>P<.001 neonatal mortality was not examined by gestational age.>

A more recent retrospective analysis of pregnancy outcomes in 81 patients with preterm PROM and preexisting cerclage between 24 and 35 weeks’ gestation suggested that the decision to remove or retain the cerclage had no effect on latency or perinatal outcome.⁶ Comparison of the cerclage patients with 162 control subjects with preterm PROM but no cerclage suggested that gestational age at presentation was the most important determinant of pregnancy outcome.⁶

 

In light of these data, Ob/Gyns should individualize the management of patients with preterm PROM and a preexisting cerclage, weighing the risk of infection against those of precipitating an extremely premature delivery with cerclage removal.

In my own practice, I have changed from being a staunch advocate of cerclage removal to a supporter of either approach, depending on individual practice style (my style remaining one of removal in the setting of preterm PROM, provided that such removal can be easily accomplished).

It is unlikely that a patient with a short cervix and no history of adverse pregnancy outcome would benefit from cerclage.

Again, we are hampered in decision-making by a paucity of data to support or refute either approach. I would emphasize the importance of dialogue, making sure the patient is aware of her options before a course of action is decided upon.

Controversy 6

Should a cerclage be placed in a woman with a short cervix?

In recent years, a number of screening tests have been introduced to identify women at increased risk of preterm delivery: biochemical tests such as fetal fibronectin,^7,8 hormonal tests such as salivary estriol,⁹ and serial cervical ultrasound examinations to assess cervical length and the presence or absence of membrane funneling.^10,11 Real-time sonographic evaluation of the cervix has demonstrated a strong inverse correlation between cervical length and preterm delivery.^10,11 If the cervical length is below the 10th percentile for gestational age, the pregnancy is at a 6-fold increased risk of delivery prior to 35 weeks.¹⁰ A cervical length of 15 mm or less at 23 weeks occurs in less than 2% of low-risk women, but is predictive of delivery prior to 28 weeks and 32 weeks in 60% and 90% of cases, respectively.¹⁰

Several retrospective studies suggest that placement of a cervical cerclage in asymptomatic women with short cervical length may improve perinatal outcome.^12-15 One study reported a 10-fold reduction in the incidence of delivery prior to 32 weeks’ gestation in women treated with cerclage, with pretermdelivery rates of 52% and 5% for women in the control and cerclage groups, respectively.¹³ These women were identified via endovaginal ultrasound as having a reduced cervical length prior to 24 weeks’ gestation.

According to more recent data, however, cerclage is not indicated in women with evidence of cervical shortening.^16,17 Indeed, 1 study showed a higher rate of preterm PROM in women undergoing cerclage, compared with those without cerclage (65.2% versus 36.5%; P<.05>17 Further studies are needed.

In essence, clinicians must tabulate all of the risks for preterm birth before selecting a course of action, with the final decision residing in a risk-benefit analysis that involves the patient. For example, it is unlikely that a patient with a short cervix (found incidentally on ultrasound) and no history of adverse pregnancy outcome would benefit from cerclage. She may, however, benefit from other screening modalities, such as ultrasound surveillance of cervical length until 24 weeks, and possibly fetal fibronectin determinations to better assess her absence of risk for preterm delivery.

On the other hand, a patient with a history of prior idiopathic preterm delivery who is found via ultrasound to have a shortened cervix may benefit from early cerclage placement.

Controversy 7

Should all DES-exposed women be offered prophylactic cerclage?

In utero exposure to DES alters the structure of the cervix in up to 69% of women.¹⁸ For example, the endocervical canal is narrower, and the demarcation between it and the lower uterine segment is less clear than in unexposed women. In addition, the cervix does not protrude as far into the vagina as in unexposed women. These and other changes can resemble alterations associated with an incompetent cervix.

Women exposed to DES are 2.6 to 6.7 times more likely than unexposed women to experience premature delivery.¹⁸ Even so, most experts have concluded that prophylactic cerclage is not indicated in patients with a history of in utero exposure to DES unless those women have experienced a previous pregnancy loss or have clear evidence of cervical shortening. One reason is the fact that the DES-exposed cervix responds differently to surgery. Further studies are required to clarify this issue.

Controversy 8

What is the role of cervical cerclage in multiple gestations?

Although multiple gestations face an increased risk of preterm delivery, there is no reliable evidence that prophylactic cerclage is helpful in uncomplicated twin pregnancies.^19-22 In fact, a randomized trial of the issue failed to reveal any advantage,²⁰ as did 2 randomized trials involving women at high risk of preterm delivery that included patients with twins.^21,22 (Women with a classic history of cervical incompetence were excluded from the latter trial.)²²

 

Because the data do not clearly support the use of cervical cerclage in higher-order multiple gestations, it is not recommended at this time. However, it appears that prophylactic cerclage may reduce extremely premature births in triplet pregnancies.²³

Complications such as infection and erosion of the cerclage into adjacent organs suggest that the cerclage should be removed once its function has been fulfilled.

Controversy 9

Should a cerclage be placed prior to pregnancy?

Cerclage placement prior to pregnancy is predicated on the assumption that avoiding manipulation of the cervix during pregnancy is desirable. This is particularly true in circumstances when the more elaborate cerclage procedures are necessary, such as abdominal or Shirodkar techniques. With these modalities, blood loss may be greater during pregnancy, and cervical manipulation may be more extensive.

Data to support or condemn this approach are insufficient, but certain practical considerations are worth mentioning. The most frequently cited risk of cerclage placement during pregnancy is loss of the pregnancy. Anatomic injury to surrounding structures may occur in either the pregnant or nonpregnant state. Placement prior to pregnancy also can be problematic if subsequent pregnancy loss occurs or a fetal anomaly is diagnosed—especially in the case of abdominal cerclage. In extreme circumstances, the need for uterine evacuation via hysterotomy could arise. There is also the theoretical risk of reduced fertility due to increased inflammation of the cervix if the cerclage is placed prior to conception.

For these reasons, coupled with improved techniques of ultrasound diagnosis and obstetric anesthesia, I opt for placement of cerclage in the late first trimester of pregnancy.

CONTROVERSY 10

Is there a role for permanent cerclage placement?

By and large, permanent cerclage placement is not recommended. Complications, including infection and erosion of the cerclage into adjacent organs, suggest that the cerclage should be removed once its function has been fulfilled. The issue of permanent cerclage placement arises almost exclusively in regard to abdominal cerclage—less often to the “true” (as opposed to modified) Shirodkar cerclage. Since cesarean delivery is necessary in cases of abdominal cerclage, the cerclage may be removed when the patient experiences what she has determined will be her final delivery.

Dr. Repke reports no affiliations or financial arrangements with any of the manufacturers of products mentioned in this article or their competitors.

THE QUESTION:
Does the risk of uterine rupture and dehiscence increase with a previous cesarean delivery?

Past studies

Prior research has demonstrated that patients undergoing a trial of labor after a cesarean delivery have an increased risk (1 in 200) of uterine rupture and dehiscence (URD).

This study

This 10-year review and case-control study examined 25,718 deliveries at a regional medical center to describe complications and identify risk factors for URD. During this period, 11 uterine ruptures and 10 uterine dehiscences occurred, along with 1 maternal death and 3 neonatal deaths. Other complications included intrapartum nonreassuring fetal status (67%), 5-minute Apgar score of less than 7 (52%), maternal blood transfusion (24%), neonatal hypoxic injury (14%), hysterectomy (14%), and endometritis (10%).

URD was independently associated with a fetal weight of greater than 8.8 lb, nonreassuring fetal status, oxytocin administration, and previous cesarean delivery. On the other hand, internal fetal monitoring was associated with a reduced risk of URD. The researchers concluded that in order to reduce the risk of URD, a delivery plan must include a cesarean history and fetal macrosomia assessment, along with the judicious use of oxytocin and intrapartum monitoring for nonreassuring fetal status.

Find this study

Diaz SD, Jones JE, Seryakov M, Mann WJ. April 2002 issue of the Southern Medical Journal; abstract online at www.medscape.com/viewarticle/432436.

Who may be affected by these findings?

Gravidas and practitioners contemplating vaginal birth after cesarean (VBAC).

Expert commentary

In the past decade, the issue of VBAC has dominated the obstetrics field. Attempts to lower cesarean-delivery rates have been fueled largely by concerns regarding cost of care. While the promotion of VBAC may save insurance companies money, the risks of a trial of labor cannot be ignored and must be thoroughly examined.

Specific factors estimating the risks or benefits of vaginal birth after cesarean remain controversial.

This study suggests that birth weight and oxytocin use may increase the risk of URD. However, these findings have not been supported by other studies.^1,2 Perhaps it is because this retrospective study harbors many limitations. For example, only symptomatic dehiscences were “discovered.” It is likely that a significant number of successful and uncomplicated VBACs sustained some degree of “bloodless dehiscence.” These, however, could not be accounted for unless routine inspection of the lower uterine segment was performed after each delivery. Another limitation of this study is the absence of labor management standards. The authors concluded that use of internal monitoring reduced the likelihood of URD, but this reduction could be a proxy for the more judicious use of uterotonic agents. Further, we do not have data regarding “decision-to-incision” intervals once fetal distress or URD was recognized.

It is important to note that the issue involved here is not one of equivalent risk, but rather, of acceptable risk, which can be determined only by the patient and her physician. At present, I’m inclined to agree with a New England Journal of Medicine editorial suggesting that if the safety of the fetus is the only consideration, elective repeat cesarean (ERC) should be the delivery of choice.³ Clearly, not every patient or clinician will see it this way.

Bottom line

The current study underscores the complexity of this issue. But while its conclusions may not be not unanimously agreed upon, the patient and the practitioner would be well advised to recognize that VBAC does indeed increase the risk of URD. Further, they should note that specific factors estimating the risks or benefits of VBAC remain controversial.

While these matters continue to be debated, facilities need to adopt a plan wherein rapid accomplishment of an emergency cesarean can occur and neonatal resuscitation personnel are immediately available.

THE QUESTION:
Does the risk of uterine rupture and dehiscence increase with a previous cesarean delivery?

Past studies

Prior research has demonstrated that patients undergoing a trial of labor after a cesarean delivery have an increased risk (1 in 200) of uterine rupture and dehiscence (URD).

This study

This 10-year review and case-control study examined 25,718 deliveries at a regional medical center to describe complications and identify risk factors for URD. During this period, 11 uterine ruptures and 10 uterine dehiscences occurred, along with 1 maternal death and 3 neonatal deaths. Other complications included intrapartum nonreassuring fetal status (67%), 5-minute Apgar score of less than 7 (52%), maternal blood transfusion (24%), neonatal hypoxic injury (14%), hysterectomy (14%), and endometritis (10%).

URD was independently associated with a fetal weight of greater than 8.8 lb, nonreassuring fetal status, oxytocin administration, and previous cesarean delivery. On the other hand, internal fetal monitoring was associated with a reduced risk of URD. The researchers concluded that in order to reduce the risk of URD, a delivery plan must include a cesarean history and fetal macrosomia assessment, along with the judicious use of oxytocin and intrapartum monitoring for nonreassuring fetal status.

Find this study

Diaz SD, Jones JE, Seryakov M, Mann WJ. April 2002 issue of the Southern Medical Journal; abstract online at www.medscape.com/viewarticle/432436.

Who may be affected by these findings?

Gravidas and practitioners contemplating vaginal birth after cesarean (VBAC).

Expert commentary

In the past decade, the issue of VBAC has dominated the obstetrics field. Attempts to lower cesarean-delivery rates have been fueled largely by concerns regarding cost of care. While the promotion of VBAC may save insurance companies money, the risks of a trial of labor cannot be ignored and must be thoroughly examined.

Specific factors estimating the risks or benefits of vaginal birth after cesarean remain controversial.

This study suggests that birth weight and oxytocin use may increase the risk of URD. However, these findings have not been supported by other studies.^1,2 Perhaps it is because this retrospective study harbors many limitations. For example, only symptomatic dehiscences were “discovered.” It is likely that a significant number of successful and uncomplicated VBACs sustained some degree of “bloodless dehiscence.” These, however, could not be accounted for unless routine inspection of the lower uterine segment was performed after each delivery. Another limitation of this study is the absence of labor management standards. The authors concluded that use of internal monitoring reduced the likelihood of URD, but this reduction could be a proxy for the more judicious use of uterotonic agents. Further, we do not have data regarding “decision-to-incision” intervals once fetal distress or URD was recognized.

It is important to note that the issue involved here is not one of equivalent risk, but rather, of acceptable risk, which can be determined only by the patient and her physician. At present, I’m inclined to agree with a New England Journal of Medicine editorial suggesting that if the safety of the fetus is the only consideration, elective repeat cesarean (ERC) should be the delivery of choice.³ Clearly, not every patient or clinician will see it this way.

Bottom line

The current study underscores the complexity of this issue. But while its conclusions may not be not unanimously agreed upon, the patient and the practitioner would be well advised to recognize that VBAC does indeed increase the risk of URD. Further, they should note that specific factors estimating the risks or benefits of VBAC remain controversial.

While these matters continue to be debated, facilities need to adopt a plan wherein rapid accomplishment of an emergency cesarean can occur and neonatal resuscitation personnel are immediately available.

THE QUESTION:
Does the risk of uterine rupture and dehiscence increase with a previous cesarean delivery?

Past studies

Prior research has demonstrated that patients undergoing a trial of labor after a cesarean delivery have an increased risk (1 in 200) of uterine rupture and dehiscence (URD).

This study

This 10-year review and case-control study examined 25,718 deliveries at a regional medical center to describe complications and identify risk factors for URD. During this period, 11 uterine ruptures and 10 uterine dehiscences occurred, along with 1 maternal death and 3 neonatal deaths. Other complications included intrapartum nonreassuring fetal status (67%), 5-minute Apgar score of less than 7 (52%), maternal blood transfusion (24%), neonatal hypoxic injury (14%), hysterectomy (14%), and endometritis (10%).

URD was independently associated with a fetal weight of greater than 8.8 lb, nonreassuring fetal status, oxytocin administration, and previous cesarean delivery. On the other hand, internal fetal monitoring was associated with a reduced risk of URD. The researchers concluded that in order to reduce the risk of URD, a delivery plan must include a cesarean history and fetal macrosomia assessment, along with the judicious use of oxytocin and intrapartum monitoring for nonreassuring fetal status.

Find this study

Diaz SD, Jones JE, Seryakov M, Mann WJ. April 2002 issue of the Southern Medical Journal; abstract online at www.medscape.com/viewarticle/432436.

Who may be affected by these findings?

Gravidas and practitioners contemplating vaginal birth after cesarean (VBAC).

Expert commentary

In the past decade, the issue of VBAC has dominated the obstetrics field. Attempts to lower cesarean-delivery rates have been fueled largely by concerns regarding cost of care. While the promotion of VBAC may save insurance companies money, the risks of a trial of labor cannot be ignored and must be thoroughly examined.

Specific factors estimating the risks or benefits of vaginal birth after cesarean remain controversial.

This study suggests that birth weight and oxytocin use may increase the risk of URD. However, these findings have not been supported by other studies.^1,2 Perhaps it is because this retrospective study harbors many limitations. For example, only symptomatic dehiscences were “discovered.” It is likely that a significant number of successful and uncomplicated VBACs sustained some degree of “bloodless dehiscence.” These, however, could not be accounted for unless routine inspection of the lower uterine segment was performed after each delivery. Another limitation of this study is the absence of labor management standards. The authors concluded that use of internal monitoring reduced the likelihood of URD, but this reduction could be a proxy for the more judicious use of uterotonic agents. Further, we do not have data regarding “decision-to-incision” intervals once fetal distress or URD was recognized.

It is important to note that the issue involved here is not one of equivalent risk, but rather, of acceptable risk, which can be determined only by the patient and her physician. At present, I’m inclined to agree with a New England Journal of Medicine editorial suggesting that if the safety of the fetus is the only consideration, elective repeat cesarean (ERC) should be the delivery of choice.³ Clearly, not every patient or clinician will see it this way.

Bottom line

The current study underscores the complexity of this issue. But while its conclusions may not be not unanimously agreed upon, the patient and the practitioner would be well advised to recognize that VBAC does indeed increase the risk of URD. Further, they should note that specific factors estimating the risks or benefits of VBAC remain controversial.

While these matters continue to be debated, facilities need to adopt a plan wherein rapid accomplishment of an emergency cesarean can occur and neonatal resuscitation personnel are immediately available.