Obstetrics

MIAMI BEACH — Oral nifedipine is a faster acting and safer tocolytic than magnesium sulfate is, findings of a recent randomized study suggest.

A total of 192 women who presented between 24 and 34 weeks' gestation with contractions and cervical change or ruptured membranes were enrolled in the study. Of those randomized to receive nifedipine, significantly fewer achieved uterine quiescence (12 hours of six or fewer contractions per hour and no further cervical change within 48 hours), compared with the magnesium sulfate group (72% vs. 87%), Dr. Deirdre J. Lyell reported at the annual meeting of the Society for Maternal-Fetal Medicine.

However, in those who achieved quiescence, nifedipine acted within 6 hours vs. 8 hours for magnesium sulfate, and 34% of patients in the nifedipine group experienced side effects, compared with 65% in the magnesium sulfate group, said Dr. Lyell of Stanford (Calif.) University.

No side effects were significantly increased with nifedipine, compared with magnesium sulfate, although there was a trend toward greater risk for headache with nifedipine. Serious side effects such as shortness of breath were significantly more common with magnesium sulfate, and the three cases of pulmonary edema seen in this study all occurred in the magnesium sulfate group. Neonatal outcomes did not differ significantly between the two groups; birth weight, composite neonatal morbidity, and individual morbidity were similar, but neonates exposed to magnesium sulfate spent a slightly higher number of days overall in neonatal intensive care, Dr. Lyell noted.

An analysis of failed tocolysis in this study showed that 12 patients failed magnesium sulfate and 28 failed nifedipine. However, of 11 patients with continued contractions who were switched to an alternative tocolytic, all were in the nifedipine group. This finding raises the question of whether there was a physician bias against nifedipine in this unblinded study, she said.

“Interestingly, the majority of magnesium sulfate failures delivered within 40 hours vs. only 30% in the nifedipine group,” she said, adding that time to delivery was significantly shorter in those with magnesium sulfate failure. Nifedipine is increasingly used as a tocolytic and was associated in two small previous studies with fewer side effects than magnesium sulfate.

MIAMI BEACH — Oral nifedipine is a faster acting and safer tocolytic than magnesium sulfate is, findings of a recent randomized study suggest.

A total of 192 women who presented between 24 and 34 weeks' gestation with contractions and cervical change or ruptured membranes were enrolled in the study. Of those randomized to receive nifedipine, significantly fewer achieved uterine quiescence (12 hours of six or fewer contractions per hour and no further cervical change within 48 hours), compared with the magnesium sulfate group (72% vs. 87%), Dr. Deirdre J. Lyell reported at the annual meeting of the Society for Maternal-Fetal Medicine.

However, in those who achieved quiescence, nifedipine acted within 6 hours vs. 8 hours for magnesium sulfate, and 34% of patients in the nifedipine group experienced side effects, compared with 65% in the magnesium sulfate group, said Dr. Lyell of Stanford (Calif.) University.

No side effects were significantly increased with nifedipine, compared with magnesium sulfate, although there was a trend toward greater risk for headache with nifedipine. Serious side effects such as shortness of breath were significantly more common with magnesium sulfate, and the three cases of pulmonary edema seen in this study all occurred in the magnesium sulfate group. Neonatal outcomes did not differ significantly between the two groups; birth weight, composite neonatal morbidity, and individual morbidity were similar, but neonates exposed to magnesium sulfate spent a slightly higher number of days overall in neonatal intensive care, Dr. Lyell noted.

An analysis of failed tocolysis in this study showed that 12 patients failed magnesium sulfate and 28 failed nifedipine. However, of 11 patients with continued contractions who were switched to an alternative tocolytic, all were in the nifedipine group. This finding raises the question of whether there was a physician bias against nifedipine in this unblinded study, she said.

“Interestingly, the majority of magnesium sulfate failures delivered within 40 hours vs. only 30% in the nifedipine group,” she said, adding that time to delivery was significantly shorter in those with magnesium sulfate failure. Nifedipine is increasingly used as a tocolytic and was associated in two small previous studies with fewer side effects than magnesium sulfate.

MIAMI BEACH — Oral nifedipine is a faster acting and safer tocolytic than magnesium sulfate is, findings of a recent randomized study suggest.

A total of 192 women who presented between 24 and 34 weeks' gestation with contractions and cervical change or ruptured membranes were enrolled in the study. Of those randomized to receive nifedipine, significantly fewer achieved uterine quiescence (12 hours of six or fewer contractions per hour and no further cervical change within 48 hours), compared with the magnesium sulfate group (72% vs. 87%), Dr. Deirdre J. Lyell reported at the annual meeting of the Society for Maternal-Fetal Medicine.

However, in those who achieved quiescence, nifedipine acted within 6 hours vs. 8 hours for magnesium sulfate, and 34% of patients in the nifedipine group experienced side effects, compared with 65% in the magnesium sulfate group, said Dr. Lyell of Stanford (Calif.) University.

No side effects were significantly increased with nifedipine, compared with magnesium sulfate, although there was a trend toward greater risk for headache with nifedipine. Serious side effects such as shortness of breath were significantly more common with magnesium sulfate, and the three cases of pulmonary edema seen in this study all occurred in the magnesium sulfate group. Neonatal outcomes did not differ significantly between the two groups; birth weight, composite neonatal morbidity, and individual morbidity were similar, but neonates exposed to magnesium sulfate spent a slightly higher number of days overall in neonatal intensive care, Dr. Lyell noted.

An analysis of failed tocolysis in this study showed that 12 patients failed magnesium sulfate and 28 failed nifedipine. However, of 11 patients with continued contractions who were switched to an alternative tocolytic, all were in the nifedipine group. This finding raises the question of whether there was a physician bias against nifedipine in this unblinded study, she said.

“Interestingly, the majority of magnesium sulfate failures delivered within 40 hours vs. only 30% in the nifedipine group,” she said, adding that time to delivery was significantly shorter in those with magnesium sulfate failure. Nifedipine is increasingly used as a tocolytic and was associated in two small previous studies with fewer side effects than magnesium sulfate.

TORONTO — Recurrent pregnancy loss was not associated with inherited maternal thrombophilias in a prospective study, adding weight to the evidence against screening for such disorders in patients presenting with a history of first-trimester miscarriage.

“It's probably more important to rule out other possible etiological factors,” said lead investigator Dr. Sony Sierra in an interview.

The study, which she presented at the annual meeting of the Society for Gynecologic Investigation, genotyped 915 Hutterite women for inherited thrombophilia polymorphisms including Factor V Leiden (FVL) Arg506Gln, the MTHFR Ala222Val, and the prothrombin G20210A variants. A total of 141 women were identified with inherited thrombophilias and were prospectively followed through 342 pregnancies.

The rate of fetal loss, defined as loss at or before 20 weeks of gestation, was 16% in the cohort, which is comparable to the rate found in the general population, reported Dr. Sierra, of the department of obstetrics and gynecology at the University of British Columbia in Vancouver.

“We also found that the majority of miscarriages occurred at less than 12 weeks—and since there has been evidence to suggest that thrombophilias could be associated with later fetal loss beyond 20 weeks, our findings just lend further support to the data that for early miscarriage there is no significant association,” she said.

Genotype analysis was performed on a subset of 72 live offspring and compared with maternal and paternal genotyping. The analysis revealed an expected transmission rate of the MTHFR Val allele to offspring; however, there were significantly fewer children born with the FVL allele (28) than expected (37). (There were no parental carriers of the prothrombin 20210A allele.)

“The significant deficit of children who inherit the FVL Gln allele from either heterozygous parent suggests that there may be preferential early loss of fetuses with this polymorphism,” said Dr. Sierra. “This unexpected result suggests selection against inherited thrombophilic variants during embryogenesis.”

TORONTO — Recurrent pregnancy loss was not associated with inherited maternal thrombophilias in a prospective study, adding weight to the evidence against screening for such disorders in patients presenting with a history of first-trimester miscarriage.

“It's probably more important to rule out other possible etiological factors,” said lead investigator Dr. Sony Sierra in an interview.

The study, which she presented at the annual meeting of the Society for Gynecologic Investigation, genotyped 915 Hutterite women for inherited thrombophilia polymorphisms including Factor V Leiden (FVL) Arg506Gln, the MTHFR Ala222Val, and the prothrombin G20210A variants. A total of 141 women were identified with inherited thrombophilias and were prospectively followed through 342 pregnancies.

The rate of fetal loss, defined as loss at or before 20 weeks of gestation, was 16% in the cohort, which is comparable to the rate found in the general population, reported Dr. Sierra, of the department of obstetrics and gynecology at the University of British Columbia in Vancouver.

“We also found that the majority of miscarriages occurred at less than 12 weeks—and since there has been evidence to suggest that thrombophilias could be associated with later fetal loss beyond 20 weeks, our findings just lend further support to the data that for early miscarriage there is no significant association,” she said.

Genotype analysis was performed on a subset of 72 live offspring and compared with maternal and paternal genotyping. The analysis revealed an expected transmission rate of the MTHFR Val allele to offspring; however, there were significantly fewer children born with the FVL allele (28) than expected (37). (There were no parental carriers of the prothrombin 20210A allele.)

“The significant deficit of children who inherit the FVL Gln allele from either heterozygous parent suggests that there may be preferential early loss of fetuses with this polymorphism,” said Dr. Sierra. “This unexpected result suggests selection against inherited thrombophilic variants during embryogenesis.”

TORONTO — Recurrent pregnancy loss was not associated with inherited maternal thrombophilias in a prospective study, adding weight to the evidence against screening for such disorders in patients presenting with a history of first-trimester miscarriage.

“It's probably more important to rule out other possible etiological factors,” said lead investigator Dr. Sony Sierra in an interview.

The study, which she presented at the annual meeting of the Society for Gynecologic Investigation, genotyped 915 Hutterite women for inherited thrombophilia polymorphisms including Factor V Leiden (FVL) Arg506Gln, the MTHFR Ala222Val, and the prothrombin G20210A variants. A total of 141 women were identified with inherited thrombophilias and were prospectively followed through 342 pregnancies.

The rate of fetal loss, defined as loss at or before 20 weeks of gestation, was 16% in the cohort, which is comparable to the rate found in the general population, reported Dr. Sierra, of the department of obstetrics and gynecology at the University of British Columbia in Vancouver.

“We also found that the majority of miscarriages occurred at less than 12 weeks—and since there has been evidence to suggest that thrombophilias could be associated with later fetal loss beyond 20 weeks, our findings just lend further support to the data that for early miscarriage there is no significant association,” she said.

Genotype analysis was performed on a subset of 72 live offspring and compared with maternal and paternal genotyping. The analysis revealed an expected transmission rate of the MTHFR Val allele to offspring; however, there were significantly fewer children born with the FVL allele (28) than expected (37). (There were no parental carriers of the prothrombin 20210A allele.)

“The significant deficit of children who inherit the FVL Gln allele from either heterozygous parent suggests that there may be preferential early loss of fetuses with this polymorphism,” said Dr. Sierra. “This unexpected result suggests selection against inherited thrombophilic variants during embryogenesis.”

MIAMI BEACH — A prenatal sonographic finding of single umbilical artery is an indication for fetal echocardiography, Dr. Lami Yeo said at the annual meeting of the Society for Maternal-Fetal Medicine.

In a case series of 430 fetuses with this finding who were identified retrospectively from a database of more than 42,600 patients, 13% had sonographic structural cardiac abnormalities, said Dr. Yeo of Robert Wood Johnson Medical School, Piscataway, N.J.

About 67% of the 430 patients had isolated single umbilical artery, and the remaining 20% had only noncardiac defects, she noted.

Of the structural cardiac abnormalities, 26% were complex cardiac defects, 26% were septal defects only, 19% were left or right hypoplastic heart, 15% were conotruncal abnormalities, 6% were defects of the atrioventricular canal, and 9% were classified as “other” defects. (Percentages add to more than 100% due to rounding.) Nearly 75% of the defects were significant defects, Dr. Yeo said.

Furthermore, 80% of those with structural cardiac defects also had other anomalies.

The patients were all diagnosed with single umbilical artery from 1994 to 2005 using color Doppler imaging around the fetal bladder. Previous studies have suggested a connection between single umbilical artery and cardiac defects, but the studies were small, and the rates varied from 2% to 23%, Dr. Yeo noted.

This series—the largest reported from a single institution—confirms the significant incidence of structural cardiac abnormalities and therefore the need for fetal echocardiography in those with a prenatal diagnosis of single umbilical artery.

MIAMI BEACH — A prenatal sonographic finding of single umbilical artery is an indication for fetal echocardiography, Dr. Lami Yeo said at the annual meeting of the Society for Maternal-Fetal Medicine.

In a case series of 430 fetuses with this finding who were identified retrospectively from a database of more than 42,600 patients, 13% had sonographic structural cardiac abnormalities, said Dr. Yeo of Robert Wood Johnson Medical School, Piscataway, N.J.

About 67% of the 430 patients had isolated single umbilical artery, and the remaining 20% had only noncardiac defects, she noted.

Of the structural cardiac abnormalities, 26% were complex cardiac defects, 26% were septal defects only, 19% were left or right hypoplastic heart, 15% were conotruncal abnormalities, 6% were defects of the atrioventricular canal, and 9% were classified as “other” defects. (Percentages add to more than 100% due to rounding.) Nearly 75% of the defects were significant defects, Dr. Yeo said.

Furthermore, 80% of those with structural cardiac defects also had other anomalies.

The patients were all diagnosed with single umbilical artery from 1994 to 2005 using color Doppler imaging around the fetal bladder. Previous studies have suggested a connection between single umbilical artery and cardiac defects, but the studies were small, and the rates varied from 2% to 23%, Dr. Yeo noted.

This series—the largest reported from a single institution—confirms the significant incidence of structural cardiac abnormalities and therefore the need for fetal echocardiography in those with a prenatal diagnosis of single umbilical artery.

MIAMI BEACH — A prenatal sonographic finding of single umbilical artery is an indication for fetal echocardiography, Dr. Lami Yeo said at the annual meeting of the Society for Maternal-Fetal Medicine.

In a case series of 430 fetuses with this finding who were identified retrospectively from a database of more than 42,600 patients, 13% had sonographic structural cardiac abnormalities, said Dr. Yeo of Robert Wood Johnson Medical School, Piscataway, N.J.

About 67% of the 430 patients had isolated single umbilical artery, and the remaining 20% had only noncardiac defects, she noted.

Of the structural cardiac abnormalities, 26% were complex cardiac defects, 26% were septal defects only, 19% were left or right hypoplastic heart, 15% were conotruncal abnormalities, 6% were defects of the atrioventricular canal, and 9% were classified as “other” defects. (Percentages add to more than 100% due to rounding.) Nearly 75% of the defects were significant defects, Dr. Yeo said.

Furthermore, 80% of those with structural cardiac defects also had other anomalies.

The patients were all diagnosed with single umbilical artery from 1994 to 2005 using color Doppler imaging around the fetal bladder. Previous studies have suggested a connection between single umbilical artery and cardiac defects, but the studies were small, and the rates varied from 2% to 23%, Dr. Yeo noted.

This series—the largest reported from a single institution—confirms the significant incidence of structural cardiac abnormalities and therefore the need for fetal echocardiography in those with a prenatal diagnosis of single umbilical artery.

ORLANDO — Pregnant women who are not heavy smokers may be more likely to successfully quit, according to research presented at the annual meeting of the Society for Research on Nicotine and Tobacco.

Lower amounts of smoking, adequate prenatal care, and higher incomes were all associated with women being more likely to quit smoking during pregnancy, said Beth Nordstrom Bailey, Ph.D., of East Tennessee State University in Johnson City. She analyzed predictors of smoking cessation among women living in rural Tennessee and Virginia, a population with a historically high rate of smoking.

Dr. Bailey conducted a chart review of 221 women who received prenatal care at a family medicine clinic in 2002 and 2003. She considered sociodemographic factors, medical factors, and substance use history. Of those women, 148 were self-identified as prepregnancy smokers. More than 60% of these smoked a pack or more a day.

Only 27% of the prepregnancy smokers were able to quit during pregnancy, 43% reduced their smoking by a quarter of a pack per day, and about 30% continued smoking at the same level.

The amount of smoking had the highest association with ability to quit. Prenatal care accounted for about 12% of the variation in quitting, Dr. Bailey said. In addition, women were more likely to quit if they had fewer prior pregnancies. Other factors such as marital status, history of depression, education, and use of drugs were not related to cessation.

ORLANDO — Pregnant women who are not heavy smokers may be more likely to successfully quit, according to research presented at the annual meeting of the Society for Research on Nicotine and Tobacco.

Lower amounts of smoking, adequate prenatal care, and higher incomes were all associated with women being more likely to quit smoking during pregnancy, said Beth Nordstrom Bailey, Ph.D., of East Tennessee State University in Johnson City. She analyzed predictors of smoking cessation among women living in rural Tennessee and Virginia, a population with a historically high rate of smoking.

Dr. Bailey conducted a chart review of 221 women who received prenatal care at a family medicine clinic in 2002 and 2003. She considered sociodemographic factors, medical factors, and substance use history. Of those women, 148 were self-identified as prepregnancy smokers. More than 60% of these smoked a pack or more a day.

Only 27% of the prepregnancy smokers were able to quit during pregnancy, 43% reduced their smoking by a quarter of a pack per day, and about 30% continued smoking at the same level.

The amount of smoking had the highest association with ability to quit. Prenatal care accounted for about 12% of the variation in quitting, Dr. Bailey said. In addition, women were more likely to quit if they had fewer prior pregnancies. Other factors such as marital status, history of depression, education, and use of drugs were not related to cessation.

ORLANDO — Pregnant women who are not heavy smokers may be more likely to successfully quit, according to research presented at the annual meeting of the Society for Research on Nicotine and Tobacco.

Lower amounts of smoking, adequate prenatal care, and higher incomes were all associated with women being more likely to quit smoking during pregnancy, said Beth Nordstrom Bailey, Ph.D., of East Tennessee State University in Johnson City. She analyzed predictors of smoking cessation among women living in rural Tennessee and Virginia, a population with a historically high rate of smoking.

Dr. Bailey conducted a chart review of 221 women who received prenatal care at a family medicine clinic in 2002 and 2003. She considered sociodemographic factors, medical factors, and substance use history. Of those women, 148 were self-identified as prepregnancy smokers. More than 60% of these smoked a pack or more a day.

Only 27% of the prepregnancy smokers were able to quit during pregnancy, 43% reduced their smoking by a quarter of a pack per day, and about 30% continued smoking at the same level.

The amount of smoking had the highest association with ability to quit. Prenatal care accounted for about 12% of the variation in quitting, Dr. Bailey said. In addition, women were more likely to quit if they had fewer prior pregnancies. Other factors such as marital status, history of depression, education, and use of drugs were not related to cessation.

MIAMI BEACH — Pelvic ultrasound is accurate for ruling out placenta accreta, and should be used as the primary screening tool in patients at high risk for this condition, Dr. Carri Warshak said at the annual meeting of the Society for Maternal-Fetal Medicine.

Magnetic resonance imaging also should be considered in the evaluation of all suspected cases, she added.

A historical cohort study of 433 patients with placenta previa who underwent ultrasound showed that this screening modality accurately predicted placenta accreta (which for the purposes of this study also included placenta increta and percreta) in 25 of the 32 women whose diagnosis was confirmed by pathologic examination, for a sensitivity of 0.78.

Ultrasound ruled out the condition in 397 of 401 patients, for a specificity of 0.99; MRI ruled out the condition in the remaining 4 patients, reported Dr. Warshak of the University of California, San Diego.

Of an additional 58 women who were referred for MRI based on equivocal ultrasound findings, 39 were shown on pathologic examination to have placenta accreta. MRI accurately predicted the condition in 35 of the 39 patients for a sensitivity of 0.90, and ruled out the condition in the remaining 19 patients for a specificity of 1.

Information for the study was obtained from a perinatal database for patients screened by ultrasound between January 2000 and June 2005 and for patients screened by MRI between January 1992 and June 2005. The findings are important because they confirm the accuracy of ultrasound and MRI for detecting a condition that requires accurate prenatal diagnosis for optimal management, she said.

Furthermore, the incidence of abnormal placentation has increased 10-fold over the past decade, largely due to the increased cesarean section rate. An estimated 9% of pregnancies are affected, she noted.

The findings confirm those from the three largest studies of ultrasound diagnosis for placenta accreta; pooled data from those studies and the current study show pelvic ultrasound is 81% sensitive and 98% specific for diagnosis, she said.

MRI has been less well studied, and results have been conflicting, but the findings of this study suggest it has an important role in optimizing diagnostic accuracy, particularly in patients with equivocal findings on ultrasound, she concluded.

MIAMI BEACH — Pelvic ultrasound is accurate for ruling out placenta accreta, and should be used as the primary screening tool in patients at high risk for this condition, Dr. Carri Warshak said at the annual meeting of the Society for Maternal-Fetal Medicine.

Magnetic resonance imaging also should be considered in the evaluation of all suspected cases, she added.

A historical cohort study of 433 patients with placenta previa who underwent ultrasound showed that this screening modality accurately predicted placenta accreta (which for the purposes of this study also included placenta increta and percreta) in 25 of the 32 women whose diagnosis was confirmed by pathologic examination, for a sensitivity of 0.78.

Ultrasound ruled out the condition in 397 of 401 patients, for a specificity of 0.99; MRI ruled out the condition in the remaining 4 patients, reported Dr. Warshak of the University of California, San Diego.

Of an additional 58 women who were referred for MRI based on equivocal ultrasound findings, 39 were shown on pathologic examination to have placenta accreta. MRI accurately predicted the condition in 35 of the 39 patients for a sensitivity of 0.90, and ruled out the condition in the remaining 19 patients for a specificity of 1.

Information for the study was obtained from a perinatal database for patients screened by ultrasound between January 2000 and June 2005 and for patients screened by MRI between January 1992 and June 2005. The findings are important because they confirm the accuracy of ultrasound and MRI for detecting a condition that requires accurate prenatal diagnosis for optimal management, she said.

Furthermore, the incidence of abnormal placentation has increased 10-fold over the past decade, largely due to the increased cesarean section rate. An estimated 9% of pregnancies are affected, she noted.

The findings confirm those from the three largest studies of ultrasound diagnosis for placenta accreta; pooled data from those studies and the current study show pelvic ultrasound is 81% sensitive and 98% specific for diagnosis, she said.

MRI has been less well studied, and results have been conflicting, but the findings of this study suggest it has an important role in optimizing diagnostic accuracy, particularly in patients with equivocal findings on ultrasound, she concluded.

MIAMI BEACH — Pelvic ultrasound is accurate for ruling out placenta accreta, and should be used as the primary screening tool in patients at high risk for this condition, Dr. Carri Warshak said at the annual meeting of the Society for Maternal-Fetal Medicine.

Magnetic resonance imaging also should be considered in the evaluation of all suspected cases, she added.

A historical cohort study of 433 patients with placenta previa who underwent ultrasound showed that this screening modality accurately predicted placenta accreta (which for the purposes of this study also included placenta increta and percreta) in 25 of the 32 women whose diagnosis was confirmed by pathologic examination, for a sensitivity of 0.78.

Ultrasound ruled out the condition in 397 of 401 patients, for a specificity of 0.99; MRI ruled out the condition in the remaining 4 patients, reported Dr. Warshak of the University of California, San Diego.

Of an additional 58 women who were referred for MRI based on equivocal ultrasound findings, 39 were shown on pathologic examination to have placenta accreta. MRI accurately predicted the condition in 35 of the 39 patients for a sensitivity of 0.90, and ruled out the condition in the remaining 19 patients for a specificity of 1.

Information for the study was obtained from a perinatal database for patients screened by ultrasound between January 2000 and June 2005 and for patients screened by MRI between January 1992 and June 2005. The findings are important because they confirm the accuracy of ultrasound and MRI for detecting a condition that requires accurate prenatal diagnosis for optimal management, she said.

Furthermore, the incidence of abnormal placentation has increased 10-fold over the past decade, largely due to the increased cesarean section rate. An estimated 9% of pregnancies are affected, she noted.

The findings confirm those from the three largest studies of ultrasound diagnosis for placenta accreta; pooled data from those studies and the current study show pelvic ultrasound is 81% sensitive and 98% specific for diagnosis, she said.

MRI has been less well studied, and results have been conflicting, but the findings of this study suggest it has an important role in optimizing diagnostic accuracy, particularly in patients with equivocal findings on ultrasound, she concluded.

TORONTO — Women whose first babies are delivered by cesarean section face an elevated risk of placenta previa and placental abruption in their second pregnancies. And with two previous cesarean deliveries the risk of placenta previa is increased further in the third pregnancy, according to a study by Dr. Darios Getahun of the Robert Wood Johnson Medical School in New Brunswick, N.J., and his colleagues.

The study, which was recently published (Obstet. Gynecol. 2006;107:771–8), was presented as a poster at the annual meeting of the Society for Gynecologic Investigation.

“Although cesarean section has previously been reported as a risk factor for placenta previa, it has not been previously associated with abruption,” Dr. Getahun said in an interview at the meeting. “Cesarean section causes scarring of the uterine wall, with the result that placentation may not be optimal. That's why it may be leading to abruption,” he explained.

The study included a cohort of women from the Missouri longitudinally linked live birth and fetal death data files. Singleton births were analyzed for 156,475 women whose first two consecutive births occurred in the 1989–1997 study period, and 31,102 women whose first three consecutive births occurred within that period.

Among 40,472 women whose first delivery was by cesarean section, the relative risk of placenta previa was 1.5, and that of placental abruption was 1.3 in the second pregnancy, compared with women whose first delivery was vaginal.

There was a dose response noted for the risk of placenta previa, but not for placental abruption risk. Therefore, when both the first and second deliveries were by cesarean section, the risk of placenta previa doubled in the third pregnancy, but the risk of placental abruption did not increase further, compared with women whose first two deliveries were vaginal.

The interval between pregnancies also was analyzed, and the study found that for cesarean deliveries, but not vaginal ones, an interval of less than 1 year was associated with a relative risk of 1.7 for placenta previa and 1.5 for placental abruption.

TORONTO — Women whose first babies are delivered by cesarean section face an elevated risk of placenta previa and placental abruption in their second pregnancies. And with two previous cesarean deliveries the risk of placenta previa is increased further in the third pregnancy, according to a study by Dr. Darios Getahun of the Robert Wood Johnson Medical School in New Brunswick, N.J., and his colleagues.

The study, which was recently published (Obstet. Gynecol. 2006;107:771–8), was presented as a poster at the annual meeting of the Society for Gynecologic Investigation.

“Although cesarean section has previously been reported as a risk factor for placenta previa, it has not been previously associated with abruption,” Dr. Getahun said in an interview at the meeting. “Cesarean section causes scarring of the uterine wall, with the result that placentation may not be optimal. That's why it may be leading to abruption,” he explained.

The study included a cohort of women from the Missouri longitudinally linked live birth and fetal death data files. Singleton births were analyzed for 156,475 women whose first two consecutive births occurred in the 1989–1997 study period, and 31,102 women whose first three consecutive births occurred within that period.

Among 40,472 women whose first delivery was by cesarean section, the relative risk of placenta previa was 1.5, and that of placental abruption was 1.3 in the second pregnancy, compared with women whose first delivery was vaginal.

There was a dose response noted for the risk of placenta previa, but not for placental abruption risk. Therefore, when both the first and second deliveries were by cesarean section, the risk of placenta previa doubled in the third pregnancy, but the risk of placental abruption did not increase further, compared with women whose first two deliveries were vaginal.

The interval between pregnancies also was analyzed, and the study found that for cesarean deliveries, but not vaginal ones, an interval of less than 1 year was associated with a relative risk of 1.7 for placenta previa and 1.5 for placental abruption.

TORONTO — Women whose first babies are delivered by cesarean section face an elevated risk of placenta previa and placental abruption in their second pregnancies. And with two previous cesarean deliveries the risk of placenta previa is increased further in the third pregnancy, according to a study by Dr. Darios Getahun of the Robert Wood Johnson Medical School in New Brunswick, N.J., and his colleagues.

The study, which was recently published (Obstet. Gynecol. 2006;107:771–8), was presented as a poster at the annual meeting of the Society for Gynecologic Investigation.

“Although cesarean section has previously been reported as a risk factor for placenta previa, it has not been previously associated with abruption,” Dr. Getahun said in an interview at the meeting. “Cesarean section causes scarring of the uterine wall, with the result that placentation may not be optimal. That's why it may be leading to abruption,” he explained.

The study included a cohort of women from the Missouri longitudinally linked live birth and fetal death data files. Singleton births were analyzed for 156,475 women whose first two consecutive births occurred in the 1989–1997 study period, and 31,102 women whose first three consecutive births occurred within that period.

Among 40,472 women whose first delivery was by cesarean section, the relative risk of placenta previa was 1.5, and that of placental abruption was 1.3 in the second pregnancy, compared with women whose first delivery was vaginal.

There was a dose response noted for the risk of placenta previa, but not for placental abruption risk. Therefore, when both the first and second deliveries were by cesarean section, the risk of placenta previa doubled in the third pregnancy, but the risk of placental abruption did not increase further, compared with women whose first two deliveries were vaginal.

The interval between pregnancies also was analyzed, and the study found that for cesarean deliveries, but not vaginal ones, an interval of less than 1 year was associated with a relative risk of 1.7 for placenta previa and 1.5 for placental abruption.

MIAMI BEACH — Continuous subcutaneous insulin lispro infusion appears to be superior to multiple daily insulin lispro injections for the treatment of pregnant women with type 1 diabetes, Dr. Giorgio Mello reported at the annual meeting of the Society for Maternal-Fetal Medicine.

In a randomized controlled study of 71 pregnant women with type 1 diabetes and 142 matched, nondiabetic, pregnant controls, continuous subcutaneous insulin infusions (CSII) were found to mimic more closely than multiple daily injections (given as a premeal bolus) the normal postprandial glucose excursion pattern.

The CSII approach also was associated with fetal fat mass growth patterns similar to those seen in normal pregnancies, said Dr. Mello of the University of Florence, Italy.

The postprandial glucose excursions were calculated as areas under the curves at 0–1, 1–2, 2–4, and 0–4 hours in the three-meal postprandial area. Patients in both treatment groups had similar average daily glucose levels throughout gestation. But at 16−, 26−, and 36-week evaluations, those in the CSII group had 24-hour glycemic profiles similar to the normal group; those in the multiple daily injections group had a significantly longer time period in the three-meal postprandial areas.

Furthermore, fetuses in the CSII group, but not in the multiple daily injection group, had growth patterns similar to those of controls, as measured by ultrasound scans performed every 2 weeks between 25 and 38 weeks' gestation. Those in the multiple daily injections group had significantly higher abdominal and midthigh fat deposition during that period, Dr. Mello noted.

MIAMI BEACH — Continuous subcutaneous insulin lispro infusion appears to be superior to multiple daily insulin lispro injections for the treatment of pregnant women with type 1 diabetes, Dr. Giorgio Mello reported at the annual meeting of the Society for Maternal-Fetal Medicine.

In a randomized controlled study of 71 pregnant women with type 1 diabetes and 142 matched, nondiabetic, pregnant controls, continuous subcutaneous insulin infusions (CSII) were found to mimic more closely than multiple daily injections (given as a premeal bolus) the normal postprandial glucose excursion pattern.

The CSII approach also was associated with fetal fat mass growth patterns similar to those seen in normal pregnancies, said Dr. Mello of the University of Florence, Italy.

The postprandial glucose excursions were calculated as areas under the curves at 0–1, 1–2, 2–4, and 0–4 hours in the three-meal postprandial area. Patients in both treatment groups had similar average daily glucose levels throughout gestation. But at 16−, 26−, and 36-week evaluations, those in the CSII group had 24-hour glycemic profiles similar to the normal group; those in the multiple daily injections group had a significantly longer time period in the three-meal postprandial areas.

Furthermore, fetuses in the CSII group, but not in the multiple daily injection group, had growth patterns similar to those of controls, as measured by ultrasound scans performed every 2 weeks between 25 and 38 weeks' gestation. Those in the multiple daily injections group had significantly higher abdominal and midthigh fat deposition during that period, Dr. Mello noted.

MIAMI BEACH — Continuous subcutaneous insulin lispro infusion appears to be superior to multiple daily insulin lispro injections for the treatment of pregnant women with type 1 diabetes, Dr. Giorgio Mello reported at the annual meeting of the Society for Maternal-Fetal Medicine.

In a randomized controlled study of 71 pregnant women with type 1 diabetes and 142 matched, nondiabetic, pregnant controls, continuous subcutaneous insulin infusions (CSII) were found to mimic more closely than multiple daily injections (given as a premeal bolus) the normal postprandial glucose excursion pattern.

The CSII approach also was associated with fetal fat mass growth patterns similar to those seen in normal pregnancies, said Dr. Mello of the University of Florence, Italy.

The postprandial glucose excursions were calculated as areas under the curves at 0–1, 1–2, 2–4, and 0–4 hours in the three-meal postprandial area. Patients in both treatment groups had similar average daily glucose levels throughout gestation. But at 16−, 26−, and 36-week evaluations, those in the CSII group had 24-hour glycemic profiles similar to the normal group; those in the multiple daily injections group had a significantly longer time period in the three-meal postprandial areas.

Furthermore, fetuses in the CSII group, but not in the multiple daily injection group, had growth patterns similar to those of controls, as measured by ultrasound scans performed every 2 weeks between 25 and 38 weeks' gestation. Those in the multiple daily injections group had significantly higher abdominal and midthigh fat deposition during that period, Dr. Mello noted.

Women who have had a baby who died from SIDS are more likely to have preterm birth or intrauterine growth restriction in their next pregnancy than are other women, reported Dr. Gordon C.S. Smith of the University of Cambridge (England) and his associates.

Similarly, women who have had a preterm or small-for-gestational-age (SGA) infant in one pregnancy are more likely to have a baby who dies from SIDS in the next pregnancy.

These associations were discovered in an analysis of large, comprehensive medical databases, and they strongly persisted when the data were adjusted for numerous maternal and demographic factors. However, the associations disappeared when gestational age and intrauterine growth restriction (IUGR) were factored into the analysis. From this finding, the investigators concluded that the link between SIDS and preterm birth/intrauterine growth restriction in other pregnancies is due to an as yet unknown maternal factor that underlies both disorders.

In the analysis, Dr. Smith and his associates reviewed information in a database on all Scottish in-hospital births, another database on all perinatal deaths in Scotland, and a third database on all Scottish birth and death records. They narrowed their study to focus on the records of 258,096 women who had one singleton birth between 1985 and 2001 and a second singleton birth between 1992 and 2001.

There were 332 women whose first infant died from SIDS, and 203 whose second infant died from SIDS, the investigators said (Lancet 2005;366:2107–11).

Women whose first infant died from SIDS were two to three times more likely to have a preterm delivery and two to three times more likely to deliver an SGA infant in the next pregnancy than were other women.

In women whose first delivery was preterm or whose first pregnancy was affected by IUGR, the risk of SIDS was elevated in the baby delivered in the subsequent pregnancy.

“We speculate that the association between SIDS in one pregnancy and obstetric complications in other pregnancies partly explains the tendency for SIDS events to recur,” they said.

Women who have had a baby who died from SIDS are more likely to have preterm birth or intrauterine growth restriction in their next pregnancy than are other women, reported Dr. Gordon C.S. Smith of the University of Cambridge (England) and his associates.

Similarly, women who have had a preterm or small-for-gestational-age (SGA) infant in one pregnancy are more likely to have a baby who dies from SIDS in the next pregnancy.

These associations were discovered in an analysis of large, comprehensive medical databases, and they strongly persisted when the data were adjusted for numerous maternal and demographic factors. However, the associations disappeared when gestational age and intrauterine growth restriction (IUGR) were factored into the analysis. From this finding, the investigators concluded that the link between SIDS and preterm birth/intrauterine growth restriction in other pregnancies is due to an as yet unknown maternal factor that underlies both disorders.

In the analysis, Dr. Smith and his associates reviewed information in a database on all Scottish in-hospital births, another database on all perinatal deaths in Scotland, and a third database on all Scottish birth and death records. They narrowed their study to focus on the records of 258,096 women who had one singleton birth between 1985 and 2001 and a second singleton birth between 1992 and 2001.

There were 332 women whose first infant died from SIDS, and 203 whose second infant died from SIDS, the investigators said (Lancet 2005;366:2107–11).

Women whose first infant died from SIDS were two to three times more likely to have a preterm delivery and two to three times more likely to deliver an SGA infant in the next pregnancy than were other women.

In women whose first delivery was preterm or whose first pregnancy was affected by IUGR, the risk of SIDS was elevated in the baby delivered in the subsequent pregnancy.

“We speculate that the association between SIDS in one pregnancy and obstetric complications in other pregnancies partly explains the tendency for SIDS events to recur,” they said.

Women who have had a baby who died from SIDS are more likely to have preterm birth or intrauterine growth restriction in their next pregnancy than are other women, reported Dr. Gordon C.S. Smith of the University of Cambridge (England) and his associates.

Similarly, women who have had a preterm or small-for-gestational-age (SGA) infant in one pregnancy are more likely to have a baby who dies from SIDS in the next pregnancy.

These associations were discovered in an analysis of large, comprehensive medical databases, and they strongly persisted when the data were adjusted for numerous maternal and demographic factors. However, the associations disappeared when gestational age and intrauterine growth restriction (IUGR) were factored into the analysis. From this finding, the investigators concluded that the link between SIDS and preterm birth/intrauterine growth restriction in other pregnancies is due to an as yet unknown maternal factor that underlies both disorders.

In the analysis, Dr. Smith and his associates reviewed information in a database on all Scottish in-hospital births, another database on all perinatal deaths in Scotland, and a third database on all Scottish birth and death records. They narrowed their study to focus on the records of 258,096 women who had one singleton birth between 1985 and 2001 and a second singleton birth between 1992 and 2001.

There were 332 women whose first infant died from SIDS, and 203 whose second infant died from SIDS, the investigators said (Lancet 2005;366:2107–11).

Women whose first infant died from SIDS were two to three times more likely to have a preterm delivery and two to three times more likely to deliver an SGA infant in the next pregnancy than were other women.

In women whose first delivery was preterm or whose first pregnancy was affected by IUGR, the risk of SIDS was elevated in the baby delivered in the subsequent pregnancy.

“We speculate that the association between SIDS in one pregnancy and obstetric complications in other pregnancies partly explains the tendency for SIDS events to recur,” they said.

PASADENA, CALIF. — Get a pregnant woman with cardiac arrest to the operating room.

That is where the best hope lies for her survival and that of her fetus, said Dr. J. Gerald Quirk at the annual meeting of the Obstetrical and Gynecological Assembly of Southern California.

“A cesarean section by you in the emergency room 2 minutes after a patient is brought in by ambulance is no better than a C-section by the side of the road by EMTs [emergency medical technicians],” said Dr. Quirk, professor and chairman of obstetrics, gynecology, and reproductive medicine at the State University of New York at Stony Brook.

Potentially reversible causes of cardiac arrest during pregnancy include hemorrhage, trauma, hypoxia, hypothermia, hyper- and hypokalemia, myocardial infarction, metabolic acidosis, and iatrogenic factors such as medication or anesthesia errors. But complex physiologic and metabolic changes of pregnancy can complicate resuscitation.

“Remember, pregnancy is a high flow, low resistance state,” he said.

Cardiac output is high, and 30% of cardiac output perfuses the uterus. Systemic vascular resistance is low. Airway management may be difficult. Left uterine displacement is necessary, as is application of cricoid pressure to avoid aspiration.

There is a need for increased chest wall compression force, “but it can be hard to know what that force is,” said Dr. Quirk. “The patient is a risk for fractured ribs and pneumothorax.”

In applicable cases, the patient may require aggressive restoration of circulatory volume as well.

The most critical issue is time, he stressed. “If you're going to attempt resuscitation, the best rule of thumb is to do it with the uterus intact for 4–5 minutes,” he said.

In the face of declining oxygen saturation—in short, “if things are not going well”—urgent preparations should be made for the operative delivery of the fetus. The OR offers three things: bright lights, the proper instruments, and an anesthesia cart. “In most hospitals, it's a very short sprint from ER to some operating room,” he said.

In the time it takes to get the patient there, an anesthesiologist and several scrub nurses are likely to be available.

If resuscitative efforts result in restoration of sinus rhythm, “you can always decide not to deliver,” said Dr. Quirk.

The imperative to perform a rapid C-section on a mother in cardiac arrest evolved after a pivotal 1982 case in which a 27-year-old primigravida of 37 weeks' gestation failed to respond to advanced cardiopulmonary resuscitation efforts following massive hemoptysis. An effort was made to save the fetus via C-section. Within moments of the delivery, the mother's pulse was detected and both the mother and infant survived without neurologic sequelae.

Several other case reports led to a “strong push” to do emergency C-sections in such patients. However, the setting is important, said Dr. Quirk.

“If one is going to entertain a perimortem C-section in hopes of salvaging both the mother and the fetus, one must first think of salvaging the mother.”

“If you're going to undertake a C-section in the emergency room, the [mother's] going to die,” he stated. “How are you going to staunch the hemorrhage?”

When the mother cannot be saved, there is still hope for the fetus, but only for a brief time.

Survival of a fetus postmortem, although the stuff of Roman lore, Greek myth, and Shakespeare, has never been actually documented until modern times. Dozens of cases have now been described, but survival of a neurologically intact infant appears to depend on a narrow window of opportunity, with a “break point” of about 15 minutes. Studies suggest that after that point, surviving infants without severe neurologic sequelae are very rare.

The OR offers three things: bright lights, the proper instruments, an anesthesia cart. DR. QUIRK

PASADENA, CALIF. — Get a pregnant woman with cardiac arrest to the operating room.

That is where the best hope lies for her survival and that of her fetus, said Dr. J. Gerald Quirk at the annual meeting of the Obstetrical and Gynecological Assembly of Southern California.

“A cesarean section by you in the emergency room 2 minutes after a patient is brought in by ambulance is no better than a C-section by the side of the road by EMTs [emergency medical technicians],” said Dr. Quirk, professor and chairman of obstetrics, gynecology, and reproductive medicine at the State University of New York at Stony Brook.

Potentially reversible causes of cardiac arrest during pregnancy include hemorrhage, trauma, hypoxia, hypothermia, hyper- and hypokalemia, myocardial infarction, metabolic acidosis, and iatrogenic factors such as medication or anesthesia errors. But complex physiologic and metabolic changes of pregnancy can complicate resuscitation.

“Remember, pregnancy is a high flow, low resistance state,” he said.

Cardiac output is high, and 30% of cardiac output perfuses the uterus. Systemic vascular resistance is low. Airway management may be difficult. Left uterine displacement is necessary, as is application of cricoid pressure to avoid aspiration.

There is a need for increased chest wall compression force, “but it can be hard to know what that force is,” said Dr. Quirk. “The patient is a risk for fractured ribs and pneumothorax.”

In applicable cases, the patient may require aggressive restoration of circulatory volume as well.

The most critical issue is time, he stressed. “If you're going to attempt resuscitation, the best rule of thumb is to do it with the uterus intact for 4–5 minutes,” he said.

In the face of declining oxygen saturation—in short, “if things are not going well”—urgent preparations should be made for the operative delivery of the fetus. The OR offers three things: bright lights, the proper instruments, and an anesthesia cart. “In most hospitals, it's a very short sprint from ER to some operating room,” he said.

In the time it takes to get the patient there, an anesthesiologist and several scrub nurses are likely to be available.

If resuscitative efforts result in restoration of sinus rhythm, “you can always decide not to deliver,” said Dr. Quirk.

The imperative to perform a rapid C-section on a mother in cardiac arrest evolved after a pivotal 1982 case in which a 27-year-old primigravida of 37 weeks' gestation failed to respond to advanced cardiopulmonary resuscitation efforts following massive hemoptysis. An effort was made to save the fetus via C-section. Within moments of the delivery, the mother's pulse was detected and both the mother and infant survived without neurologic sequelae.

Several other case reports led to a “strong push” to do emergency C-sections in such patients. However, the setting is important, said Dr. Quirk.

“If one is going to entertain a perimortem C-section in hopes of salvaging both the mother and the fetus, one must first think of salvaging the mother.”

“If you're going to undertake a C-section in the emergency room, the [mother's] going to die,” he stated. “How are you going to staunch the hemorrhage?”

When the mother cannot be saved, there is still hope for the fetus, but only for a brief time.

Survival of a fetus postmortem, although the stuff of Roman lore, Greek myth, and Shakespeare, has never been actually documented until modern times. Dozens of cases have now been described, but survival of a neurologically intact infant appears to depend on a narrow window of opportunity, with a “break point” of about 15 minutes. Studies suggest that after that point, surviving infants without severe neurologic sequelae are very rare.

The OR offers three things: bright lights, the proper instruments, an anesthesia cart. DR. QUIRK

PASADENA, CALIF. — Get a pregnant woman with cardiac arrest to the operating room.

That is where the best hope lies for her survival and that of her fetus, said Dr. J. Gerald Quirk at the annual meeting of the Obstetrical and Gynecological Assembly of Southern California.

“A cesarean section by you in the emergency room 2 minutes after a patient is brought in by ambulance is no better than a C-section by the side of the road by EMTs [emergency medical technicians],” said Dr. Quirk, professor and chairman of obstetrics, gynecology, and reproductive medicine at the State University of New York at Stony Brook.

Potentially reversible causes of cardiac arrest during pregnancy include hemorrhage, trauma, hypoxia, hypothermia, hyper- and hypokalemia, myocardial infarction, metabolic acidosis, and iatrogenic factors such as medication or anesthesia errors. But complex physiologic and metabolic changes of pregnancy can complicate resuscitation.

“Remember, pregnancy is a high flow, low resistance state,” he said.

Cardiac output is high, and 30% of cardiac output perfuses the uterus. Systemic vascular resistance is low. Airway management may be difficult. Left uterine displacement is necessary, as is application of cricoid pressure to avoid aspiration.

There is a need for increased chest wall compression force, “but it can be hard to know what that force is,” said Dr. Quirk. “The patient is a risk for fractured ribs and pneumothorax.”

In applicable cases, the patient may require aggressive restoration of circulatory volume as well.

The most critical issue is time, he stressed. “If you're going to attempt resuscitation, the best rule of thumb is to do it with the uterus intact for 4–5 minutes,” he said.

In the face of declining oxygen saturation—in short, “if things are not going well”—urgent preparations should be made for the operative delivery of the fetus. The OR offers three things: bright lights, the proper instruments, and an anesthesia cart. “In most hospitals, it's a very short sprint from ER to some operating room,” he said.

In the time it takes to get the patient there, an anesthesiologist and several scrub nurses are likely to be available.

If resuscitative efforts result in restoration of sinus rhythm, “you can always decide not to deliver,” said Dr. Quirk.

The imperative to perform a rapid C-section on a mother in cardiac arrest evolved after a pivotal 1982 case in which a 27-year-old primigravida of 37 weeks' gestation failed to respond to advanced cardiopulmonary resuscitation efforts following massive hemoptysis. An effort was made to save the fetus via C-section. Within moments of the delivery, the mother's pulse was detected and both the mother and infant survived without neurologic sequelae.

Several other case reports led to a “strong push” to do emergency C-sections in such patients. However, the setting is important, said Dr. Quirk.

“If one is going to entertain a perimortem C-section in hopes of salvaging both the mother and the fetus, one must first think of salvaging the mother.”

“If you're going to undertake a C-section in the emergency room, the [mother's] going to die,” he stated. “How are you going to staunch the hemorrhage?”

When the mother cannot be saved, there is still hope for the fetus, but only for a brief time.

Survival of a fetus postmortem, although the stuff of Roman lore, Greek myth, and Shakespeare, has never been actually documented until modern times. Dozens of cases have now been described, but survival of a neurologically intact infant appears to depend on a narrow window of opportunity, with a “break point” of about 15 minutes. Studies suggest that after that point, surviving infants without severe neurologic sequelae are very rare.

The OR offers three things: bright lights, the proper instruments, an anesthesia cart. DR. QUIRK

PASADENA, CALIF. — The Heimlich maneuver becomes unwieldy during the late stages of pregnancy, requiring adaptations, Dr. J. Gerald Quirk said at the annual meeting of the Obstetrical and Gynecological Assembly of Southern California.

Breast enlargement, diaphragm displacement, and the size and weight of a pregnant woman all contribute to difficulty in performing the traditional emergency maneuver to prevent choking during late pregnancy.

First described in 1974 by Dr. Henry Heimlich, a thoracic surgeon, the Heimlich maneuver involves standing behind a choking victim and placing a fist, thumb side in, underneath the diaphragm.

Using the other hand to push against the fist, a series of abrupt upward thrusts can usually dislodge a piece of food from the airway.

Not only is it difficult to hold a woman in this position during late pregnancy, it is also hard to exert the force necessary to perform the maneuver correctly, said Dr. Quirk, professor and chair of obstetrics, gynecology, and reproductive medicine at Stony Brook (N.Y.) University.

“The best thing to do is lay her on the floor and press down on the lower part of the sternum,” he said.

The woman should be tilted slightly to one side to prevent aortocaval compression.

Dr. Quirk said several case reports suggest that this adaptation is effective in late pregnancy.

PASADENA, CALIF. — The Heimlich maneuver becomes unwieldy during the late stages of pregnancy, requiring adaptations, Dr. J. Gerald Quirk said at the annual meeting of the Obstetrical and Gynecological Assembly of Southern California.

Breast enlargement, diaphragm displacement, and the size and weight of a pregnant woman all contribute to difficulty in performing the traditional emergency maneuver to prevent choking during late pregnancy.

First described in 1974 by Dr. Henry Heimlich, a thoracic surgeon, the Heimlich maneuver involves standing behind a choking victim and placing a fist, thumb side in, underneath the diaphragm.

Using the other hand to push against the fist, a series of abrupt upward thrusts can usually dislodge a piece of food from the airway.

Not only is it difficult to hold a woman in this position during late pregnancy, it is also hard to exert the force necessary to perform the maneuver correctly, said Dr. Quirk, professor and chair of obstetrics, gynecology, and reproductive medicine at Stony Brook (N.Y.) University.

“The best thing to do is lay her on the floor and press down on the lower part of the sternum,” he said.

The woman should be tilted slightly to one side to prevent aortocaval compression.

Dr. Quirk said several case reports suggest that this adaptation is effective in late pregnancy.

PASADENA, CALIF. — The Heimlich maneuver becomes unwieldy during the late stages of pregnancy, requiring adaptations, Dr. J. Gerald Quirk said at the annual meeting of the Obstetrical and Gynecological Assembly of Southern California.

Breast enlargement, diaphragm displacement, and the size and weight of a pregnant woman all contribute to difficulty in performing the traditional emergency maneuver to prevent choking during late pregnancy.

First described in 1974 by Dr. Henry Heimlich, a thoracic surgeon, the Heimlich maneuver involves standing behind a choking victim and placing a fist, thumb side in, underneath the diaphragm.

Using the other hand to push against the fist, a series of abrupt upward thrusts can usually dislodge a piece of food from the airway.

Not only is it difficult to hold a woman in this position during late pregnancy, it is also hard to exert the force necessary to perform the maneuver correctly, said Dr. Quirk, professor and chair of obstetrics, gynecology, and reproductive medicine at Stony Brook (N.Y.) University.

“The best thing to do is lay her on the floor and press down on the lower part of the sternum,” he said.

The woman should be tilted slightly to one side to prevent aortocaval compression.

Dr. Quirk said several case reports suggest that this adaptation is effective in late pregnancy.