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)

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)

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.

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)

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.

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.

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.

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.

Urinary estriols in diabetic pregnancy: a reappraisal.

The clinical usefulness of serial urinary estriols was tested in 138 insulin-dependent diabetic pregnant women. No action was taken on an estriol drop if fetal well-being was demonstrated by a reactive nonstress test and/or negative contraction stress test within 24 hours. Of 3085 estriol values, a greater than or equal to 40% estriol drop, confirmed by a greater than or equal to 40% decrease in the estriol-creatine ratio, was observed in 21 tests. In only two of these tests, was fetal distress indicated by a nonstress test or contraction stress test. A significant linear correlation was demonstrated between the mean level of estriol excretion and birth weight, placental weight, and fetal abdominal circumference measured by ultrasound. Chronically low estriol excretion (less than 12 mg per 24 hours at greater than 36 weeks' gestation) related to smaller placentas but not to fetal jeopardy.

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.

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.

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.

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.

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.

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.

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.

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).

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.