Preference assessment of prenatal diagnosis for Down syndrome: is 35 years a rational cutoff?

OBJECTIVE

To compare the perceptions of miscarriage and birth of a child with Down syndrome among pregnant women and to evaluate the implications of these preferences for the traditional 35-year old maternal age risk boundary.

METHODS

An interviewer-administered survey was given to 186 pregnant women receiving antepartum care at a university hospital. Preferences, as reflected by utilities, for birth of a child with Down syndrome and pregnancy miscarriage, stratified by patient characteristics, were assessed.

RESULTS

The utility for the birth of a child with Down syndrome decreased (p < 0.001) as clinical severity increased from mild (0.78) to severe (0.65). Miscarriage of a pregnancy had a mean utility of 0.76 +/- 0.31. Women who desired prenatal diagnosis had a utility value for miscarriage (0.79 +/- 0.28) that was significantly higher than for the birth of a child with Down syndrome of unknown severity (0.73 +/- 0.27). In multivariable logistic regression, desire for prenatal diagnosis was the only factor associated with a preference of miscarriage over birth of an affected child (odds ratio 2.26, 95% confidence interval 1.03, 4.96).

CONCLUSION

Women who desire prenatal diagnosis do not perceive the birth of a child with Down syndrome and a pregnancy miscarriage to be equivalent health states. This finding calls into question the rationale of the 35-year-old maternal age criterion and suggests that actual patient preferences should be better incorporated into the decision to offer definitive prenatal diagnosis.

Indomethacin tocolysis and risk of necrotizing enterocolitis

OBJECTIVE

To investigate the possible association of indomethacin tocolysis with neonatal necrotizing enterocolitis.

METHODS

A case-control study was performed for the period November 1, 1997, through May 1, 1999. All cases of proven necrotizing enterocolitis were ascertained, and four controls for each case were randomly identified from all Special Care Nursery admissions before 37 weeks' gestation without necrotizing enterocolitis during that same period.

RESULTS

During the 18-month period there were 24 cases of necrotizing enterocolitis out of 10,200 deliveries. Infants with necrotizing enterocolitis were more preterm (29.7 +/- 3.9 compared with 32.7 +/- 6.0 weeks; P =.03) and had lower birth weights (1453 +/- 777 compared with 1820 +/- 678 g; P =.02) compared with controls (n = 96). Respiratory distress syndrome (RDS) and sepsis were both significantly associated with an increased risk of necrotizing enterocolitis: 16 of 24 cases compared with 40 of 96 controls had RDS (odds ratio [OR] 2.8, 95% confidence interval [CI] 1.0, 8.3) and 14 of 24 cases compared with 11 of 96 controls were septic (OR 10.8, 3.4, 95% CI 34.2). Indomethacin as a single agent was not associated with necrotizing enterocolitis (OR 1.0, 95% CI 0.2, 4.8). Using a logistic regression model, necrotizing enterocolitis was strongly associated with sepsis (adjusted OR 8.5, 95% CI 2.2, 32.5). When sepsis was removed from the model, double-agent tocolytic therapy was significantly associated with necrotizing enterocolitis (adjusted OR 6.9, 95% CI 1.1, 43.6).

CONCLUSION

Tocolysis with indomethacin as a single agent was not associated with necrotizing enterocolitis in this case-control study. Combination tocolytic therapy may be a marker for subclinical infection and not causally related to necrotizing enterocolitis.

Is the management of epidural analgesia associated with an increased risk of cesarean delivery?

OBJECTIVE

The aim of this study was to quantify the association of cesarean delivery with epidural analgesia management, specifically with the timing of epidural catheter placement in relation to labor, the type of epidural analgesia, and the use of bolus dosing.

STUDY DESIGN

A retrospective cohort design was used to investigate 1561 consecutive nulliparous parturients whose labor occurred between November 1, 1996, and June 30, 1997, at Northwestern Memorial Hospital and who were delivered of term, singleton neonates in a cephalic presentation. The relationship between the management of epidural analgesia and the risk for cesarean delivery was determined with stepwise logistic regression to control for potential confounding variables.

RESULTS

There was a significantly increased risk of cesarean delivery associated with decrements in cervical effacement (P =.001), cervical dilatation (P =.001), and fetal station (P =.001) at the time of epidural catheter placement. An increasing number of epidural boluses during the first stage of labor was also associated with increased risk of cesarean delivery (P =.001). After we controlled for maternal age, maternal body mass index, gestational age, infant birth weight, induction of labor, use of magnesium sulfate, and presence of chorioamnionitis, the adjusted odds of cesarean delivery associated with fetal station (odds ratio, 1.45; 95% confidence interval, 1.2-1.7) and epidural boluses (odds ratio, 1.55; 95% confidence interval, 1.3-1.8) during the first stage of labor remained significant.

CONCLUSION

The management of epidural analgesia during labor was associated with the potential for increased risk of cesarean delivery. This risk increased with higher stations of the fetal head at the time of epidural catheter placement and with more frequent epidural boluses of local anesthetic during the first stage of labor.

Evaluation of the centrifuged and Gram-stained smear, urinalysis, and reagent strip testing to detect asymptomatic bacteriuria in obstetric patients

OBJECTIVE

Our purpose was to compare the efficacy of the centrifuged and Gram-stained smear with the efficacy of both urinalysis and reagent strip testing for nitrites and leukocyte esterase in detecting asymptomatic bacteriuria in obstetric patients.

STUDY DESIGN

A midstream urine specimen was evaluated in 528 patients either at the initial prenatal visit or at a visit because of possible preterm labor. Separate aliquots were tested by centrifugation (with a Cytospin Cytocentrifuge; Shandon, Inc, Pittsburgh, Pa) with Gram stain, by microscopic urinalysis for the presence of moderate to large numbers of bacteria or >10 leukocytes per high-power field, and by reagent strips for the presence of nitrites or leukocyte esterase activity. Results were compared with those of a quantitative urine culture obtained with blood and MacConkey agar plates.

RESULTS

Thirty-six women (6.8%) had urine cultures showing 100,000 colony-forming units of a uropathogen per milliliter. The sensitivity and specificity of testing by centrifugation and Gram stain were 100% and 7.7%, respectively. Urinalysis and dipstick testing offered a sensitivity of 80.6% and 47.2%, respectively, with a specificity of 71.5% and 80.3%. No combination of tests, in series or in parallel, offered improved specificity over urinalysis alone.

CONCLUSIONS

Centrifugation with Gram stain of a urine specimen offers excellent sensitivity but very poor specificity compared with microscopic urinalysis for the detection of asymptomatic bacteriuria and is not an acceptable screening test in an obstetric population. The false-negative rates of urinalysis (19.4%) and reagent strip testing (52.8%) preclude these from being excellent screening tests for asymptomatic bacteriuria. Given the potential sequelae of undiagnosed asymptomatic bacteriuria in an obstetric population, we conclude that urine cultures should be used for all pregnant patients to detect asymptomatic bacteriuria.

Routine ultrasound in pregnancy

The interest in studying routine ultrasound in pregnancy has provided useful results that can be applied to practice. There is no consistent evidence of risk caused by ultrasound, neither biologic risk for the fetus nor increased use of health services as a result of ascertained conditions. There is also no consistent benefit to routine ultrasound in terms of important health outcomes. In the United States, this finding may be related to the excellent care provided to women in the usual-care arm of trials and possibly also to practice patterns. For example, with a high background induction rate in the United States, the prevalence of perinatal morbidity from post-term pregnancy may be so low that differences could not be ascertained between routine-ultrasound and usual care arms of the RADIUS study. The evidence from the use of ultrasound to screen for anomalies reveals substantial concern regarding interobserver variability, as might be expected when using a test for screening that requires considerable skill. The range of observed sensitivities underscores the disadvantages of performing basic ultrasound on a routine basis rather than on selected patients. Because routine ultrasound can reduce perinatal deaths in a population of women who would consider pregnancy termination, pretest counseling may identify a subset of women for whom screening may be effective in improving health outcomes. This remains to be demonstrated in the United States.

Risk of cesarean delivery with elective induction of labor at term in nulliparous women

OBJECTIVE

To quantify the risk of cesarean delivery associated with elective induction of labor in nulliparous women at term.

METHODS

We performed a cohort study on a major urban obstetric service that serves predominantly private obstetric practices. All term, nulliparous women with vertex, singleton gestations who labored during an 8-month period (n = 1561) were divided into three groups: spontaneous labor, elective induction, and medical induction. The risk of cesarean delivery in the induction groups was determined using stepwise logistic regression to control for potential confounding factors.

RESULTS

Women experiencing spontaneous labor had a 7.8% cesarean delivery rate, whereas women undergoing elective labor induction had a 17.5% cesarean delivery rate (adjusted odds ratio [OR] 1.89; 95% confidence interval [CI] 1.12, 3.18) and women undergoing medically indicated labor induction had a 17.7% cesarean delivery rate (OR 1.69; 95% CI 1.13, 2.54). Other variables that remained significant risk factors for cesarean delivery in the model included: epidural placement at less than 4 cm dilatation (OR 4.66; 95% CI 2.25, 9.66), epidural placement after 4 cm dilatation (OR 2.18; 95% CI 1.06, 4.48), chorioamnionitis (OR 4.61; 95% CI 2.89, 7.35), birth weight greater than 4000 g (OR 2.59; 95% CI 1.69, 3.97), maternal body mass index greater than 26 kg/m2 (OR 2.36; 95% CI 1.61, 3.47), Asian race (OR 2.35; 95% CI 1.04, 5.34), and magnesium sulfate use (OR 2.18; 95% CI 1.04, 4.55).

CONCLUSION

Elective induction of labor is associated with a significantly increased risk of cesarean delivery in nulliparous women. Avoiding labor induction in settings of unproved benefit may aid efforts to reduce the primary cesarean delivery rate.

Risk adjustment for interhospital comparison of primary cesarean rates

OBJECTIVE

To create a method of controlling for case mix so that inferences could be made about variation in cesarean rates among hospitals.

METHODS

A total of 160,753 births from 1991 Illinois birth certificate data were analyzed. A multivariate model of characteristics independently associated with cesarean delivery was developed from a random 25% sample, validated on the other 75%, and used to create a probability of cesarean delivery for each woman. The validated model was used to calculate a predicted primary cesarean delivery rate for the 154 hospitals in Illinois that did at least 100 deliveries per year.

RESULTS

The final model included both medical and sociodemographic risk factors and predicted primary cesarean rates accurately over a full range of rates. Thirty-five hospitals (23%) had actual rates that were higher than their individual predicted 95% confidence interval (CI). Eighty-nine hospitals (58%) had actual rates within predicted CIs. Thirty hospitals (20%) had actual rates that were lower than the predicted 95% CI. Twenty-three percent of hospitals with actual rates greater than predicted rates were not in the top quartile of actual rates. Twenty-seven percent of hospitals with actual rates in the top quartile were doing cesarean deliveries appropriate for the risk status of the population served.

CONCLUSION

Risk adjusting for hospital case mix more accurately identifies outlier hospitals than raw, unadjusted primary cesarean delivery rates. We believe that risk adjusting should be the first step in understanding variations in primary cesarean delivery rates.

Reversal of diurnal cortisol rhythm and suppression of plasma testosterone in obstetric residents on call

OBJECTIVE

The study was undertaken to quantify the psychologic and physiologic responses to the stresses of an obstetrics/gynecology residency program.

METHODS

Six male residents were studied on four occasions: one day during the first 2 weeks of their residency, one day immediately following a vacation period, one day after a night on call in obstetrics, and one day while in the gynecology clinic. Stress was evaluated by validated psychologic instruments and by levels of plasma testosterone, luteinizing hormone (LH), cortisol, and prolactin in morning and afternoon blood samples.

RESULTS

Self-reported stress was significantly elevated during the first 2 weeks of the residency after a night on call. Anxiety scores were significantly elevated after a night on call as were depression subscores for some residents. Plasma testosterone was highly significantly suppressed after the obstetrics night on call and during the first 2 weeks of the residency in comparison with the vacation period. Luteinizing hormone levels were also significantly lower after the obstetrics on-call experience. Plasma cortisol levels after a night on call were suppressed in the morning and normal or elevated in the afternoon. In comparison, the gynecology rotation was associated with normal levels of testosterone and lower levels of cortisol.

CONCLUSION

In this small sample of residents, we observed an inverse relationship between self-reported stress levels and the concentrations of plasma testosterone and LH. The high levels of stress and anxiety expressed after a night on call also disrupted the normal pattern of plasma cortisol levels.

Risk factors for cesarean delivery in twin gestations near term

OBJECTIVE

We evaluated the risk factors associated with cesarean delivery in laboring twin gestations at least 36 completed weeks.

METHODS

We reviewed the records of 134 women with twin gestations who underwent a trial of labor between 1993 and 1995. Women who delivered by cesarean were compared with women who delivered vaginally. The factors associated with an increased risk for cesarean were determined using univariate analysis. Logistic regression was used to determine which of those factors was most strongly associated with cesarean delivery.

RESULTS

Of 134 laboring twin gestations, 25 (18.7%) delivered by cesarean and 109 (81.3%) delivered vaginally. Univariate analysis revealed that women who delivered by cesarean were more likely to be nulliparous, have a less advanced cervix at both admission and epidural placement, a higher mean oxytocin infusion rate for induction or augmentation of labor, a combined fetal weight greater than 5500 g, and received magnesium for seizure prophylaxis. Multivariate analysis identified that nulliparity and timing of epidural administration were the factors most strongly associated with cesarean delivery.

CONCLUSION

The timing of epidural analgesia is a modifiable risk factor strongly associated with cesarean delivery in term and near-term laboring twin gestations.

Quality assessment of perinatal regionalization by multivariate analysis: Illinois, 1991-1993

OBJECTIVE

To identify (1) those elements in the infrastructure of a regionalized perinatal network that have independent effects on the variation in perinatal mortality among nontertiary units (member level I and II hospitals) and (2) shortcomings, if any, in a traditional perinatal data base that impede quality assessment of contemporary regionalized care.

METHODS

We analyzed perinatal surveillance data for 3 years, from 1991 to 1993, in the state of Illinois, representing more than 190,000 annual births. Fetal death and neonatal mortality rates for the 97 nontertiary hospitals studied were the dependent variables of interest. Two sets of independent variables were studied, those assessing the maternal sociobehavioral risk of populations served and those assessing the network infrastructure (defined as the facilities of member hospitals and their function within the regionalized network). We used multivariate analysis to partition the variation in hospital rates of perinatal mortality into two components, one attributable to maternal sociobehavioral risk and the other to the network infrastructure.

RESULTS

Maternal sociobehavioral risk alone explained 73% of the variation in hospital fetal death rates and 38% of that in hospital neonatal mortality rates. When controlling for maternal sociobehavioral risk, rates of inborn very low birth weight (VLBW) deliveries (P < .001) and neonatal transport (P = .01) had independent effects on the variation in hospital fetal death rate; rates of inborn VLBW deliveries (P < .001), neonatal transport (P < .001), and proportion of VLBW infants transported out (P = .029) had independent effects on the variation in hospital neonatal mortality rate.

CONCLUSIONS

In this mature statewide network, the rate of inborn VLBW deliveries exerted the strongest independent effect on variation in level I and II hospital rates of both fetal death and neonatal mortality. However, that there was such a large effect from maternal sociobehavioral risk alone has important public health implications. Additions and modifications to traditional perinatal surveillance are suggested better to assess the quality of regionalization in a contemporary health care environment.

Early malnutrition and child neurobehavioral development: insights from the study of children of diabetic mothers

In this study we sought to discern whether disturbances in mothers' metabolism during pregnancy may exert long-range effects on the neurobehavioral development of the progeny. Participants were 139 women with diabetes in pregnancy and their singleton offspring. Serial estimates of circulating maternal fuels were obtained for each pregnancy, along with detailed records of perinatal course and outcome. Offspring were administered the Wechsler Intelligence Scale for Children--Revised (WISC-R) and Kaufman Test of Educational Achievement: Short Form (KTEA) at ages 7 to 11 years. The rate of WISC-R full-scale IQ scores below 70 in our cohort did not differ significantly from national estimates. Nonetheless, after statistically controlling for other influences, WISC-R verbal, performance, and full-scale IQ scores, and Bannatyne's indices of Verbal Conceptualization Ability, Acquired knowledge, Spatial Ability, and Sequencing Ability were inversely correlated with measures of maternal lipid and glucose metabolism in the second and third trimesters. KTEA Arithmetic scores were similarly correlated with measures of maternal lipids in the third trimester. All correlations indicate that poorer maternal metabolic regulation was attended by poorer child performance. The effects of maternal metabolism on fetal brain and neurobehavioral development are discussed as potential intermediary factors.

Metabolic response to meal eating and extended overnight fast in twin gestation

OBJECTIVE

Our purpose was to compare the metabolic response to normal meal eating and the vulnerability to starvation ketosis in twin versus singleton gestation.

STUDY DESIGN

Data are reported on 10 twin and 10 singleton nondiabetic gestations enrolled in a 40-hour metabolic study. Singletons were age (+/- 5 years) and prepregnancy weight (+/- 10% ideal body weight) matched with twins. The diet (35 kcal/kg ideal body weight for singletons, 40 kcal/kg ideal body weight for twins) was distributed as one fifth at 8 AM, two fifths at 1 PM, and two fifths at 6 PM. An overnight fast was extended until noon the following day. Glucose and beta-hydroxybutyrate measurements were made hourly except at night, when they were made every 2 hours. Insulin values were obtained before and after dinner and on the day when breakfast was delayed.

RESULTS

The glucose, beta-hydroxybutyrate, and insulin excursions in response to meal eating from 8 AM to 12:00 noon on day 1 were similar in twin and singleton pregnancies (analysis of variance for repeated measures, p < 0.05). On day 2, when breakfast was delayed, a progressive decrement in glucose was observed in both twins and singletons (p = 0.4682). Concurrently, there was a progressive rise in beta-hydroxybutyrate in both twins and singletons, which was significantly greater for twins compared with singletons (p = 0.002).

CONCLUSIONS

These data indicate that twin gestations are more vulnerable to the accelerated starvation of late normal pregnancy than singletons are in spite of additional caloric intake. We speculate that the observed difference may be the result of the increased metabolic demands of twin gestation.

Effect of pregnancy on renal function in patients with moderate-to-severe diabetic renal insufficiency

OBJECTIVE

Previous studies of patients with diabetic nephropathy and mild renal impairment have suggested no determination in renal function as a result of pregnancy. The objective of this study was to determine whether pregnancy may permanently worsen renal function in women with diabetic nephropathy and moderate-to-severe renal insufficiency.

RESEARCH DESIGN AND METHODS

Eleven patients were identified with diabetic nephropathy and moderate-to-severe renal dysfunction (creatinine [Cr] > or = 124 mumol/l [1.4 mg/dl]) at pregnancy onset by retrospective chart review. Alterations in glomerular filtration rate were estimated by using linear regression of the reciprocal of Cr over time. An equal number of nonpregnant premenopausal type 1 diabetic women with similar degrees of renal dysfunction served as a comparison group for nonpregnant rate of decline of renal function and potential contributing factors.

RESULTS

Mean serum Cr rose from 159 mumol/l (1.8 mg/dl) prepregnancy to 221 mumol/l (2.5 mg/dl) in the third trimester. Renal function was stable in 27%, showed transient worsening in pregnancy in 27%, and demonstrated a permanent decline in 45%. Proteinuria increased in pregnancy in 79%. Exacerbation of hypertension or preeclampsia occurred in 73%. Seven patients progressed to dialysis 6-57 months postpartum, with 71% (five of seven) of these cases attributed to acceleration of disease during the pregnancy. Student's tests and repeated-measures analysis of variance support a pregnancy-induced acceleration in the rate of decline of renal function.

CONCLUSIONS

In this series, patients with diabetic nephropathy and moderate-to-severe renal insufficiency were found to have a > 40% chance of accelerated progression of their disease as a result of pregnancy.

Prenatal and perinatal influences on long-term psychomotor development in offspring of diabetic mothers

OBJECTIVE

Our purpose was to assess to what extent disturbances in antepartum maternal metabolism and perinatal complications and morbidities contribute to poorer psychomotor development in offspring of diabetic mothers.

STUDY DESIGN

One hundred ninety-six pregnant women and their singleton offspring participated in this prospective cohort-analytic study. Ninety-five women had pregestational diabetes mellitus, and 101 women had gestational diabetes mellitus. Serial estimates of circulating maternal fuels were obtained throughout each index pregnancy along with detailed records of the perinatal course and outcome. Offspring were administered the psychomotor development index of the Bayley Scales of Infant Development at age 2 years and the Bruininks-Oseretsky Test Of Motor Proficiency at ages 6, 8, and 9 years. Tests were performed blinded to the mother's antepartum metabolic status, and perinatal history, and the child's previous test scores. Partial correlations and analyses of covariance were used to control for other influences and confounds, such as family socioeconomic status, racial or ethnic origin, patient group (i.e., pregestational or gestational diabetes mellitus), and sex of child.

RESULTS

Children's average score on the Bruininks-Oseretsky test at ages 6 to 9 years correlated significantly with maternal second (p < 0.02) and third trimester (p < 0.001) beta-hydroxybutyrate. There was also a borderline association between the children's scores on the psychomotor development index at age 2 years and maternal third-trimester beta-hydroxybutyrate levels (p = 0.06). No other correlations approached significance.

CONCLUSIONS

Intrauterine metabolic experiences continue to influence the neurodevelopmental course in offspring of diabetic mothers. Prevailing practices in diabetes management and obstetric and neonatal care appear to effectively mitigate the potential long-term effects of most perinatal complications and morbidities. Management and obstetric and neonatal care appear to effectively miltigate the potential long-term effects of most perinatal complications and morbidities.

Screening for gestational diabetes mellitus in Korea

OBJECTIVES

To examine the effect of clinical characteristics on the prevalence of gestational diabetes mellitus (GDM) and to find the most effective screening program for GDM in Korea.

METHODS

Universal screening with a 50-g glucose load at 24-28 weeks' gestation, as recommended by the Third International Workshop-Conference on Gestational Diabetes Mellitus, was carried out among 3581 consecutive Korean women. Women with a 1-h plasma glucose > or = 130 mg/dl underwent a 3-h 100-g oral glucose tolerance test. The women's clinical characteristics and risk factors for GDM were recorded at the time of the screening test.

RESULTS

The overall prevalence of GDM in Korean women was 2.2 cases/100. Although only 1.3% of this population was obese, the prevalence of GDM was found to be significantly increased with increasing body mass index. When 135 mg/dl is used as a threshold, the number of women requiring a diagnostic test decreases to 19.5%, enabling identification of 98.8% of women with GDM.

CONCLUSION

Universal screening using 135 mg/dl as a threshold and early screening of those with two or more risk factors represent the most effective paradigm for Korea.

A randomized trial of extra-amniotic saline infusion versus laminaria for cervical ripening

OBJECTIVE

To compare extra-amniotic saline infusion versus laminaria for cervical ripening and labor induction.

METHODS

Patients of at least 34 weeks' gestation with a Bishop score of 3 or less were randomized to either laminaria ripening for 6 hours or more followed by oxytocin induction versus initiation of extra-amniotic saline infusion at the start of oxytocin induction. Indications for induction included 41 weeks' gestation or greater, hypertensive disease, diabetes, oligohydramnios, suspect fetal growth, and nonreassuring fetal testing.

RESULTS

There were no significant differences in maternal age, race, parity, gestational age, or indications for induction between the two groups (extra-amniotic saline infusion group, n = 26, laminaria group, n = 26). After only 3 hours of oxytocin induction, patients in the extra-amniotic saline infusion group achieved an identical distribution of Bishop scores compared with the patients in the laminaria group after 6 hours or more of pre-induction ripening as well as 3 hours of oxytocin induction. There were no differences in rates of cesarean delivery (extra-amniotic saline infusion 35%, laminaria 35%), infectious complications, or neonatal outcomes between the two groups. The induction-to-delivery interval (+/- standard deviation) was significantly shortened with extra-amniotic saline infusion (extra-amniotic saline infusion 12.9 +/- 5.7 hours versus laminaria 16.9 +/- 7.1 hours, P = .03). In addition, fewer cesarean deliveries were performed for failed inductions (cervix less than 5 cm dilated) in the extra-amniotic saline infusion group (one of 26 versus six of 26, P = .049).

CONCLUSION

Extra-amniotic saline infusion offers potential advantages over the use of laminaria. Extra-amniotic saline infusion saves a significant amount of time both by obviating the need for pre-induction cervical ripening and in shortening the induction-to-delivery interval. Also, fewer patients required cesarean delivery for failed induction of labor with extra-amniotic saline infusion.

Perinatal complications and cognitive development in 2- to 5-year-old children of diabetic mothers

OBJECTIVE

Our purpose was to assess whether perinatal complications contribute to lower intellectual attainment in offspring of diabetic mothers, independent of antepartum metabolic disregulation.

STUDY DESIGN

Subjects were 223 pregnant women and their singleton offspring. Eighty-nine women had pregestational diabetes mellitus, 99 had gestational diabetes mellitus, and 35 had normal gestational glucose metabolism. Perinatal complications were prospectively recorded on an examination checklist. The intelligence quotient of the child was assessed with the Bayley Scales of Infant Development at age 2 years and the Stanford-Binet Intelligence Scale at age 3 to 5 years.

RESULTS

No significant correlations emerged between either measure of child's intelligence quotient and any prevalent perinatal complication, after statistical correction for socioeconomic status, race or ethnic origin, patient group, and antepartum metabolic control.

CONCLUSIONS

Given prevailing practices in diabetes management and obstetric and neonatal care, the effects of prevalent perinatal complications on the intellectual development of offspring of diabetic mothers appear minimal.

The efficacy of oral terbutaline after intravenous tocolysis

OBJECTIVE

Our purpose was to investigate in a prospective, randomized study the efficacy of oral terbutaline after successful intravenous tocolysis in reducing preterm birth.

STUDY DESIGN

Patients between 28 and 35 weeks' gestation with uterine contractions and change in cervical examination were treated with intravenous magnesium sulfate for 12 to 24 hours. After successful tocolysis patients were approached for study participation and randomized to receive either oral terbutaline or no therapy. The dose of terbutaline was individualized to achieve a maternal pulse > 100 beats/min, and terbutaline was continued until 36 completed weeks of gestation. Recurrent preterm labor (contractions with change in cervical examination) for either group was treated with intravenous magnesium sulfate, and subsequent treatment was based on the previous randomization.

RESULTS

Fifty-five patients were enrolled (28 terbutaline, 27 no oral tocolytic). No difference was found between groups with respect to time gained (4.0 +/- 2.7 vs 4.6 +/- 3.1 weeks, p = 0.412), gestational age at delivery (35.6 +/- 2.7 vs 36.1 +/- 2.4 weeks, p = 0.562), > or = 37 weeks at delivery (nine vs 13, p = 0.291), recurrent preterm labor (10 vs four, p = 0.104), recurrent uterine contractions alone (five vs eight, p = 0.527), birth weight (2616 +/- 633 gm vs 2645 +/- 599 gm, p = 0.785), special care nursery admissions (eight vs six, p = 0.759), or neonatal respiratory distress syndrome (three vs two, p = 0.965).

CONCLUSION

The use of oral terbutaline after successful parenteral tocolysis failed to reduce the rate of preterm birth.

Reducing cesarean births at a primarily private university hospital

OBJECTIVE

The rise in cesarean birth at Northwestern Memorial Hospital in 1986 to 27.3% prompted implementation of three initiatives to reverse the escalating cesarean section rate.

STUDY DESIGN

First, vaginal birth after cesarean section was more strongly encouraged. Second, after the 1988 calendar year the cesarean section rate of every obstetrician was circulated annually to each attending physician. Third, on completion of a prospective, randomized trial of the active management of labor in early 1991, this protocol was recommended as the preferred method of labor management for term nulliparous patients.

RESULTS

The total, primary, and repeat cesarean section rates declined from 27.3%, 18.2%, and 9.1% in 1986 to 16.9%, 10.6%, and 6.4%, respectively, in 1991. At the same time the perinatal mortality dropped from 19.5 to 10.3. Significant reductions in abdominal deliveries occurred for both private patients (30.3% to 19.1%, p < 0.0001) and clinic patients (20.8% to 11.5%, p < 0.0001). A decline in operative deliveries for dystocia and an increase in vaginal birth after prior cesarean section were the principal factors contributing to the lower cesarean section rates. However, in 1991 individual private physicians still had wide variations in primary cesarean section rates (4.6% to 21.1%) and use of vaginal birth after prior cesarean section (5.3% to 90%).

CONCLUSION

The cesarean section rate has been significantly reduced for both private and clinic patients. Differences in population demographics and individual physician practice patterns contributed to a higher incidence of cesarean birth on the private service.

Iatrogenic respiratory distress syndrome following elective repeat cesarean delivery

OBJECTIVE

To determine the incidence of iatrogenic respiratory distress syndrome (RDS) following elective repeat cesarean delivery and to identify whether it was associated with departures from accepted management guidelines.

METHODS

Between January 1986 and March 1991, there were 23,125 deliveries at Northwestern Memorial Hospital, of which 1207 were repeat cesarean births without labor. During this period, 18 neonates of 37 weeks' gestation or greater or 2500 g or greater who were delivered by elective repeat cesarean were admitted to the neonatal intensive care unit (NICU) for respiratory difficulties.

RESULTS

Five of the 18 neonates admitted to the NICU with respiratory difficulty following elective repeat cesarean delivery met the criteria for RDS. This represents an incidence of 0.41% (five of 1207), or one case of RDS for every 241 repeat cesarean deliveries without labor. Four of the five neonates required mechanical ventilation for an average of 6.8 days. The average NICU stay was 11.2 days. Complications included pneumothorax (one) and pulmonary hemorrhage (one). Departures from accepted management guidelines included a discrepancy between ultrasound and menstrual dates (two), no confirmation of menstrual dates (one), and delivery before 39 weeks' gestation (two).

CONCLUSION

Iatrogenic RDS continues to occur in the setting of elective repeat cesarean delivery and is associated with a failure to adhere to clinical protocols.

Antepartum management of triplet gestations

OBJECTIVE

We evaluated an alternative approach to the management of triplet gestations that did not include home uterine monitoring, prophylactic tocolysis, or routine antepartum hospitalization.

STUDY DESIGN

Fifteen patients were managed over a 42-month period by an antepartum protocol that emphasized patient education regarding signs and symptoms of preterm labor, weekly prenatal visits after 24 weeks' gestation with cervical examination, and increased rest in an outpatient setting. Tocolytic therapy was only used for regular uterine contractions when cervical change was documented.

RESULTS

Nine of 15 (60%) patients with management in this uniform manner were delivered at > or = 35 weeks' gestation, and six patients (40%) completed 37 weeks of pregnancy. Only five patients (33%) received tocolytic therapy. The mean birth weight was 1957 +/- 488 gm, and only 19 of 45 neonates (42%) were admitted to the intensive care nursery.

CONCLUSION

This management scheme was effective in reducing preterm delivery and thereby optimizing perinatal outcome.

Gestational diabetes mellitus. Influence of race on disease prevalence and perinatal outcome in a U.S. population

We explore whether racial differences in a United States population influence disease prevalence and perinatal outcome in gestational diabetes mellitus (GDM). The data presented are based on 3744 consecutive patients who underwent universal screening at 24-28 wk gestation; those with a 1-h plasma glucose greater than or equal to 7.2 mM underwent a 100-g 3-h oral glucose tolerance test (OGTT). The overall prevalence of GDM was 3.5 cases/100 with the standard O'Sullivan-Mahan diagnostic criteria derived for plasma, whereas use of the Carpenter-Coustan modification of the O'Sullivan-Mahan criteria yielded a prevalence of 5.5. The population was 39.1% white, 37.7% black, 19.8% Hispanic, and 3.4% Oriental/other. For those patients with a nondiagnostic test, mean plasma glucose at each time point of the OGTT was similar for all racial groups. Because of demographic and phenotypic heterogeneity between different racial groups, the influence of these different variables on the prevalence of GDM was tested by multiple logistic regression. Black and Hispanic race, maternal age, and percentage ideal body weight were found to have significant independent effects on the prevalence of GDM (P less than 0.05, 0.001, 0.001, and 0.001, respectively). The adjusted relative risk of GDM was significantly higher in black (1.81, 95% confidence interval [CI] 1.13-2.89, P less than 0.05) and Hispanic (2.45, 95% CI 1.48-4.04, P less than 0.001) patients compared with whites. The influence of race on infant birth weight was examined in the 92 patients with GDM controlled with diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Absence of hyperinsulinemia in isoimmunized fetuses treated with intravascular transfusion

We serially sampled blood from fetuses of five severely isoimmunized pregnancies at the time of each intrauterine intravascular transfusion and at birth. We were unable to demonstrate either an elevation in the plasma insulin/glucose ratio or a relationship between the insulin/glucose ratio and hemoglobin concentration at any time period. Plasma total glutathione concentration, however, decreased dramatically from the initial to the second transfusion (323 +/- 114 to 43 +/- 9 ng/ml; t = -5.06, p less than 0.01). We speculate that intrauterine transfusion may modify or prevent the previously reported fetal pancreatic beta-cell hyperplasia and hyperinsulinemia associated with isoimmunization by decreasing red blood cell hemolysis and thereby circulating glutathione.

Shoulder dystocia and birth trauma in gestational diabetes: a five-year experience

Over a 5-year period, 210 patients with gestational diabetes mellitus were delivered of offspring weighing greater than or equal to 3500 gm. Only three primary cesarean sections were performed electively because of suspected macrosomia. One hundred twenty patients were delivered vaginally. There were 15 shoulder dystocias but only one permanent brachial plexus injury. Seven of the 15 shoulder dystocias occurred in offspring weighing less than 4000 gm. Of variables examined, only the use of forceps was clearly associated with an increased risk of shoulder dystocia (odds ratio, 5.1). A policy to deliver by cesarean section all fetuses estimated to weigh greater than 4000 gm would considerably increase the number of cesarean sections with minimal fetal benefit.

Perinatal outcome following intravascular transfusion in severely isoimmunized fetuses

Twenty-six severely isoimmunized pregnancies managed exclusively with ultrasonographically guided intravascular fetal transfusions are reported. The mean gestational age plus and minus one standard deviation (+/- SD) was 26.3 +/- 3.6 weeks and the mean hematocrit (+/- SD) prior to initial transfusion was 20.6 +/- 6.7%. Four of seven hydropic fetuses and 9 of 19 without hydrops were less than or equal to 26 weeks gestation at the first transfusion. Overall survival was 85% (22/26). Survival was similar whether or not fetal hydrops was present (6/7 vs. 16/19) and whether or not the first transfusion was administered at less than or equal to 26 weeks gestation (10/13 vs. 12/13).

The influence of demographic and phenotypic heterogeneity on the prevalence of gestational diabetes mellitus

In order to explore the influence of demographic and phenotypic characteristics on the prevalence of gestational diabetes mellitus (GDM), data were analyzed from 3744 consecutive patients who underwent universal screening with a 50 g glucose load at 24-28 weeks gestational age. Those with a 1-h plasma glucose greater than or equal to 130 mg/dl underwent a 3-h, 100-g oral glucose tolerance test following dietary preparation. The population was 39.1% White, 37.7% Black, 19.8% Hispanic and 3.4% Oriental/other. The overall prevalence of GDM was 3.5 cases/100. Significant inter-racial differences in maternal age and prepregnant percent ideal body weight (PIBW) were observed, with White patients being older and leaner than Blacks and Hispanics. By multiple logistic regression, Black and Hispanic race, maternal age and PIBW were found to have significant independent effects on the prevalence of GDM. Controlling for age and PIBW, the adjusted relative risk of GDM was significantly higher in Black (1.81, 95% CI 1.13-2.89) and Hispanic (2.45, 95% CI 1.48-4.04) patients compared to White. We conclude that demographic and phenotypic characteristics of populations need to be taken into consideration in future studies of prevalence of GDM, perinatal implications and therapeutic approaches to the disease.

Northwestern University Twin Study X: Outcome of twin gestations complicated by gestational diabetes mellitus

Existing data concerning the effect of gestational diabetes on perinatal outcome in twin pregnancies is scant. We hypothesized that altered carbohydrate metabolism would worsen perinatal outcome in twin gestation in a manner similar to singleton gestation. Thirteen twin pregnancies complicated by gestational diabetes mellitus were matched by gestational age at delivery to 13 twin pregnancies unaffected by gestational diabetes. Comparing infants of diabetic mothers to infants of control mothers, there was a trend of greater likelihood of respiratory distress syndrome, hyperbilirubinemia, and prolonged neonatal intensive care nursery admissions. Our experience suggests that altered carbohydrate metabolism in multiple gestations increases the potential for neonatal morbidity.

Is intrauterine transfusion associated with diminished fetal growth?

Studies in animal models and human pregnancies suggest that severe fetal anemia and/or replacement of fetal with adult blood result in decreased pH, increased base deficit, and hyperlactacidemia. Similar changes have been noted in growth-retarded, nonanemic fetuses, and we therefore hypothesized that isoimmunized fetuses requiring intrauterine transfusions might have diminished growth. We longitudinally studied growth patterns in 17 isoimmunized fetuses by noting biparietal diameter and head and abdominal circumference measurements at each transfusion. The distributions of these measurements above and below the 25th, 50th, and 75th percentiles derived from our general obstetric population were compared at the initial transfusion and the last ultrasonogram performed before delivery. Birth weights also were noted and their distribution around the 25th, 50th, and 75th percentiles was compared to the expected distribution. For each ultrasonographic parameter, the distribution of measurements at the last ultrasonogram before delivery was not significantly different from the distribution at the initial ultrasonogram. The birth weight distribution also was not significantly different than the expected distribution. Thus we were unable to demonstrate slowing of fetal growth in our severely isoimmunized pregnancies.

Amniotic fluid insulin concentration as a predictor of obesity

Longitudinal correlations were obtained between amniotic fluid insulin concentration at 32 to 38 weeks' gestation and anthropometric characteristics at the age of 6 years in 56 children of diabetic mothers. The prospective studies indicated that at the age of 6 years, as at birth, the greatest increase in weight in relation to height (relative obesity) was seen in children who experienced the greatest exposures to insulin in the uterus (as judged by amniotic fluid insulin concentration). Significant correlations between amniotic fluid insulin and relative obesity at the age of 6 years were found after adjustment for maternal obesity and macrosomia at birth. The highest amniotic fluid insulin values are clustered in the subgroup of 14 children who were obviously obese by the age of 6 years. These findings are consistent with the hypothesis that there is an association between anthropometric development and intrauterine metabolism, and suggest that premature and excessive exposure to insulin during gestation may predispose to obesity in childhood. The amniotic fluid insulin concentration may predict this eventuality.

Infants of diabetic mothers with accelerated fetal growth by ultrasonography: are they all alike?

We studied longitudinal ultrasonographic growth patterns (abdominal circumference, biparietal diameter) initiated early in gestation in 52 pregnancies complicated by pregestational diabetes mellitus and 19 controls. Three predominant patterns of growth were ascertained including a heretofore unrecognized pattern characterized by accelerated abdominal circumference growth (greater than 90th percentile) before 24 weeks' gestational age. Maternal and neonatal anthropometric and metabolic parameters were contrasted for the three patterns. The findings suggest that in some cases of diabetic macrosomia that can be recognized before 24 weeks' gestation, augmented growth may be influenced by factors other than fetal hyperinsulinism.

Effects of intravascular, intrauterine transfusion on prenatal and postnatal hemolysis and erythropoiesis in severe fetal isoimmunization

In an investigation of the effects of intrauterine, intravascular transfusions (IUT) on fetal and neonatal hemolysis and erythropoiesis, 12 fetuses who received IUT for treatment of severe isoimmunization had serial measurements of hemoglobin concentration, Kleihauer-Betke stains to detect fetal hemoglobin-containing erythrocytes, and determination of plasma erythropoietin (EPO) concentration before each IUT, at birth, and postnatally. Reticulocyte counts and sensitizing antibody titers were measured in five fetuses. Mean values before the first IUT, before the final IUT, and at birth were as follows: hemoglobin level, 6.1, 9.1, and 11.3 gm/dl; reticulocyte count, 22.7%, 0.5%, and 0.9%; fetal hemoglobin-containing erythrocytes, 100%, 1.6%, and 1.5%; and EPO level, 12, 56, and 756 mU/ml, respectively. Only one neonate required exchange transfusion. In the first month postnatally, all infants had a profound anemia. All but one infant required simple blood transfusions postnatally. Before the first postnatal transfusion, mean hemoglobin concentration was 6.2 gm/dl, mean reticulocyte count was 0.8%, mean erythropoietin concentration was 23 mU/ml, and the sensitizing antibody titer remained markedly elevated. Except for the surge of EPO at birth, EPO levels did not rise prenatally or postnatally unless marked anemia (hemoglobin level less than 5 gm/dl) occurred. These observations suggest that the intrauterine and postnatal anemia in fetuses who receive IUTs may be explained both by hemolysis of newly formed erythrocytes by circulating antibody, which typically persisted for more than a month after birth, and by suppressed erythropoiesis.

Amniotic fluid prolactin in the third trimester of pregnancies complicated by gestational or pregestational diabetes mellitus

Amniotic fluid concentrations of immunoreactive prolactin were measured during the third trimester in 184 diabetic gravidas and correlated with concurrent levels of prolactin in maternal plasma. Prolactin measurements concorded with previously published estimates in normal gravid women and averaged 825 +/- 32 ng/mL (mean +/- SEM) in amniotic fluid and 168 +/- 6.5 ng/mL in simultaneously sampled plasma. Cross-sectional and longitudinal analyses indicated that the prolactin levels in amniotic fluid of pregnant diabetics declined significantly between weeks 32 and 40 of gestation, whereas plasma levels did not change consistently during the same interval. Mean values for amniotic fluid prolactin did not correlate with simultaneous prolactin concentrations in plasma, nor with maternal age, clinical estimates of polyhydramnios, amniotic fluid creatinine content, or lecithin/sphingomyelin (L/S) ratios or subsequent birth weight of the offspring. Clear-cut correlations with overall maternal glucose regulation could not be demonstrated. However, subtle effects may be operative since amniotic fluid prolactin displayed weak but significant correlations with concurrent levels of maternal plasma glucose, and mean values for hemoglobin A1c (HbA1c) but not with mean values for fasting plasma glucose (FPG). Amniotic fluid prolactin concentrations were significantly greater in patients with pregestational diabetes (White classes C, D, and F) than in women with gestational diabetes mellitus (GDM) (our classes A1, A2, and B1). The differences could not be accounted for by differences in metabolic regulation, maternal age, or weights of these two populations.(ABSTRACT TRUNCATED AT 250 WORDS)

The prevalence of substance abuse in patients with suspected preterm labor

Premature labor is a recognized complication of substance abuse in pregnancy. However, the prevalence of substance abuse in patients first seen with symptoms of preterm labor and who deny use of illicit drugs is unknown. Between July 1, 1988, and December 15, 1988, 141 patients first seen at Northwestern Memorial Hospital in suspected preterm labor and a comparison group of 108 uncomplicated laboring term patients had urine toxicology screening performed to detect substance abuse. Positive urine toxicology screenings were found in 24 of 141 (17.0%) patients with suspected preterm labor and in 3 of 108 (2.8%) patients in the comparison group. The most common substance identified was cocaine (14/24 and 1/3, respectively). Of those patients in suspected preterm labor, 22 of 86 (25.6%) clinic patients had positive urine toxicology screenings as did 2 of 55 (3.6%) private patients. On the basis of our observations, we recommend that patients admitted in possible preterm labor be encouraged to submit to screening for substance abuse so that appropriate counseling and prenatal and neonatal care become available for these high-risk patients.

Factors influencing hemostasis after umbilical vein puncture in vitro

Bleeding from the site of cordocentesis can be detected by ultrasound examination, but significant hemorrhage into the amniotic fluid rarely occurs. To evaluate the relative contribution of amniotic fluid thromboplastins and the quantity of Wharton's jelly in facilitating coagulation at the puncture site, amniotic fluid samples and umbilical cord segments were obtained at cesarean section from 20 patients. After puncture of the umbilical vein, bleeding times were measured in amniotic fluid and 0.9% sodium chloride. The quantity of Wharton's jelly was assessed by measuring umbilical cord circumference. Mean bleeding times were significantly shorter in amniotic fluid compared with saline solution, but there was no consistent relationship between bleeding times and umbilical cord circumference. We conclude that properties of amniotic fluid facilitate coagulation at the site of umbilical vein puncture.

Cordocentesis: an appraisal of risks

Fetal blood sampling via cordocentesis is being used with increasing frequency. Between March 1986 and February 1988, we performed 58 intravascular transfusions (64 attempts) and 27 fetal blood samplings (28 attempts) guided by ultrasonography. The complication rates for intravascular transfusion and fetal blood sampling were 9.4% (6 of 64) and 7.1% (2 of 28), respectively. The procedure-related mortality rates were 4.7% (3 of 64) and 0%. We caution that the potential complications be seriously considered when appropriate patients are selected for cordocentesis. Additionally, we recommend that cordocentesis be performed only in tertiary care centers by personnel skilled in both ultrasonography and prenatal diagnosis.

Fetal acidosis in prolonged pregnancy cannot be attributed to cord compression alone

Fetal heart rate abnormalities associated with prolonged pregnancy have been attributed to umbilical cord vulnerability rather than placental insufficiency. Although intrapartum fetal heart rate patterns indicative of umbilical cord compression are common beyond 41 weeks' gestation, fetal intolerance to labor develops only in a subset of such patients. To test the hypothesis that suboptimal placental function contributes to reduced amniotic fluid volume and, ultimately, to fetal intolerance to labor, we prospectively collected biochemical and clinical data on 112 prolonged pregnancies. Data analysis was blinded to outcome and included cord blood acid-base measurements and intrapartum fetal heart rate interpretation. We observed a high incidence of umbilical cord compression (46.4%), but this finding was not predictive of emergent delivery in 32 of 52 cases (61.5%). Fetal acidosis (arterial pH less than 7.20) occurred more often in patients with cord compression, but the anticipated increase in carbon dioxide tension was not observed. Instead, a primary metabolic or combined acidosis was encountered in those fetuses delivered emergently. The additional findings of lower amniotic fluid volume and diminished birth weight in those patients delivered for fetal intolerance to labor suggest a direct role for suboptimal placental function in selected patients with prolonged pregnancy.

Fetal heart rate changes after fetal intravascular treatment with pancuronium bromide

Because of recurrent needle dislodgement secondary to fetal movement, we have altered our intravascular transfusion technique by replacing maternal premedication (meperidine and diazepam [group 1]) with fetal intravascular infusion of pancuronium bromide (Pavulon [group 2]), a nondepolarizing neuromuscular blocking agent. Baseline fetal heart rate, number of accelerations, and variability were assessed before and after transfusion in both groups. Whereas there were no changes after transfusion in the former group, those fetuses who received pancuronium bromide demonstrated a dramatic abolishment of accelerations and decrease in variability, with the heart rate pattern often appearing "sinusoidal-like." These alterations in fetal heart rate were temporary changes that reverted to normal once the fetus "awakened" from the neuromuscular blockade. We speculate that these changes in fetal heart rate are secondary to the interaction of the reported hypertensive and vagolytic effects of pancuronium bromide.

Apgar scores and umbilical cord arterial pH in the breech neonate

Apgar scores and umbilical cord arterial pH measurements of 449 singleton breech deliveries are compared retrospectively to those of 1425 singleton vertex neonates. In the vaginal deliveries the Apgar scores and umbilical arterial pH were higher for the vertex neonates. There were no differences in either Apgar scores or umbilical arterial pH between the breech and vertex neonates delivered by cesarean section. Whereas Apgar scores in the less than 1000 g and greater than or equal to 2500 g weight groups were lower in the breech neonates delivered vaginally compared to cesarean section, umbilical arterial pH measurements were similar. The data suggest that liberal use of cesarean section may improve the Apgar scores but will probably not appreciably improve the acid-base status of the breech neonate.

Umbilical cord size and amniotic fluid volume in prolonged pregnancy

Expectant management of prolonged pregnancy is predicated on reassuring biophysical testing. However, even the combination of a reactive nonstress test and normal amniotic fluid volume may not prevent subsequent morbidity. To test the hypothesis that diminished cord Wharton's jelly incurs risk of peripartum cord compression in addition to decreased amniotic fluid, 68 patients with confirmed gestational age greater than or equal to 41 weeks were evaluated prospectively with semiweekly nonstress tests and weekly ultrasound examinations. Amniotic fluid volume was assessed, and umbilical cord diameter was measured and then correlated with the quantity of Wharton's jelly at delivery, determined by cord circumference. A significant correlation between cord circumference and umbilical cord diameter was observed, even in those patients with decreased amniotic fluid volume. Either an amniotic fluid volume less than 3.8 cm or an umbilical cord diameter less than 1.6 cm was associated with significant cord compression patterns. Peripartum morbidity was greatest in the presence of a smaller cord and decreased fluid, suggesting a synergism between these two factors for the risk of cord compression in prolonged pregnancy.

Gestational diabetes mellitus: a syndrome with phenotypic and genotypic heterogeneity

One hundred ninety-nine gravida with gestational diabetes mellitus (GDM) defined as "carbohydrate intolerance of varying severity with onset or first recognition during pregnancy" have been stratified into subgroups on the basis of fasting plasma glucose and evaluated for further phenotypic and genotypic heterogeneity. A significantly greater proportion of the women in all our groups were older and heavier than in a "control" population of 148 consecutive gravida with documented normal oral glucose tolerance. After correction for age and weight by covariate analysis, absolute insulinopenia in response to oral glucose could be demonstrated in all GDM groups, although exceptions were present in each. The incidence of diabetes in the mothers of our patients with GDM was 8-fold greater than in controls; the incidence in fathers did not deviate from control patterns. HLA-DR3 and DR4 antigens were more frequently present in GDM and the increase was statistically significant in blacks. At the time of diagnosis, cytoplasmic islet cell antibodies (ICA) were significantly more common in GDM associated with elevated fasting plasma glucose than in controls; the frequency of ICA was 18.4% (7/38) in women with fasting plasma glucose greater than or equal to 130 mg/dl. Our findings indicate that GDM entails genotypic as well as phenotypic diversity and may include patients with slowly-evolving Type I diabetes mellitus, as well as patients with Type II diabetes mellitus, and women with asymptomatic diabetes which antedated the pregnancy (i.e. pregestational diabetes mellitus). Appreciation of this heterogeneity should be incorporated into any evaluation of intervention strategies for women with GDM or into prognoses concerning their postpartum metabolic status.

Diabetic macrosomia: accuracy of third trimester ultrasound

Sonar biparietal diameter, head circumference, and abdominal circumference percentile values obtained late in the third trimester were compared with birth weight percentile (relative to dates) in 147 diabetic mothers and 40 control fetuses of nondiabetics. Estimates of fetal weight by the method of Shepard et al were also calculated from these sonar data and compared with birth weight percentile. Abdominal circumference values greater than the 90th percentile correctly predicted macrosomia (defined as birth weight greater than 90th percentile) in 78% of cases. Biparietal diameter and head circumference percentiles were significantly less predictive of macrosomia. When analyzed in a similar manner, estimated fetal weights greater than the 90th percentile correctly predicted macrosomia at birth in 74% of cases. However, when both the abdominal circumference and the estimated fetal weight exceeded the 90th percentile, macrosomia was correctly diagnosed in 88.8% of pregnant women with diabetes mellitus.

Meconium below the vocal cords at delivery: correlation with intrapartum events

Intrapartum events were studied in 272 patients with meconium-stained amniotic fluid. All infants underwent DeLee suction followed by intubation and 58 of 272 had meconium present below the vocal cords at delivery. Neither the total duration of variable fetal heart rate decelerations or a continuous saltatory pattern nor the presence or absence of late decelerations could be related to an increased risk of meconium below the vocal cords. When a rising baseline fetal heart rate and decreased variability were present as well, a significantly greater proportion of patients had meconium below the vocal cords. Routine obstetric and pediatric suctioning did not prevent the single death that occurred in a fetus who had deep meconium aspiration in utero.

Real-time ultrasound estimations of weight in fetuses of diabetic gravid women

To test the applicability of equations for fetal weight estimations in a group of fetuses suspected of being large for gestational age, real-time ultrasound measurements of fetal biparietal diameters and abdominal circumferences were obtained for 34 fetuses of diabetic mothers. In the first phase of the study the accuracy in the prediction of weight was assessed with use of two known equations. In the second phase, biparietal diameter, abdominal circumference, and actual birth weight data of the 34 study fetuses were used as independent variables to determine the best-fitting equation for relating estimated fetal weight (EFW) to biparietal diameter (BPD) and abdominal circumference (AC); this equation is log (EFW) = 0.02597 AC + 0.2161 BPD - 0.1999 (AC X BPD2)/1000 + 1.2659. The standard deviation of differences is 322.26 gm and multiple R = 0.781. In the final phase the reliability of this equation was compared to those of Thurnau and Shepard in 34 additional fetuses of diabetic gravid women. The data suggest that in these fetuses suspected of being large for gestational age the weight estimates calculated at or near term may be enhanced if predictive equations are formulated specifically from the data for such fetuses.

Gestational diabetes mellitus. Heterogeneity of maternal age, weight, insulin secretion, HLA antigens, and islet cell antibodies and the impact of maternal metabolism on pancreatic B-cell and somatic development in the offspring

We have examined gravida with gestational diabetes mellitus (GDM), as defined by the National Diabetes Data Group (Diabetes 1979; 28:1039), for phenotypic and genotypic heterogeneity. Fasting plasma glucose (FPG) at diagnosis was used for further stratification of GDM according to putative metabolic severity into class A1 (FPG less than 105 mg/dl [N = 129]), class A2 (FPG 105-129 mg/dl [N = 47]), and class B1 (FPG greater than or equal to 130 mg/dl [N = 23]). All GDM classes tended to be older and heavier than consecutive gravida with documented normal glucose tolerance (controls, N = 148). Subdivision into "lean" and "obese" indicated that plasma immunoreactive insulin (IRI) was greater after overnight fast in the obese of all groups except B1. However, absolute increases in IRI above fasting levels in response to glucose during OGTT were significantly enhanced by obesity only in class A2 gravida. Adjustment for the effects of age and weight by covariate analysis indicated that the IRI response to glycemic stimulation is usually attenuated in all forms of GDM. Mean values for increases in IRI above fasting values during the first 15 min and IRI increments relative to the increases in plasma glucose throughout the 180-min OGTT were below control values in all GDM groups and progressively so, i.e., A1 less than A2 less than B1. The absolute insulinopenia was not invariable; a small number of gravida from all GDM groups displayed well-preserved IRI responses to oral glucose. Genotypic evaluation of the GDM population disclosed an increased occurrence of "markers" known to be associated with type I diabetes mellitus.(ABSTRACT TRUNCATED AT 250 WORDS)