Fetal Tachycardia in the Setting of Maternal Intrapartum Fever and Perinatal Morbidity

OBJECTIVE

 The fetal consequences of intrapartum fetal tachycardia with maternal fever or clinical chorioamnionitis are not well studied. We evaluated the association between perinatal morbidity and fetal tachycardia in the setting of intrapartum fever.

STUDY DESIGN

 Secondary analysis of a multicenter randomized control trial that enrolled 5,341 healthy laboring nulliparous women ≥36 weeks' gestation. Women with intrapartum fever ≥ 38.0°C (including those meeting criteria for clinical chorioamnionitis) after randomization were included in this analysis. Isolated fetal tachycardia was defined as fetal heart rate (FHR) ≥160 beats per minute for at least 10 minutes in the absence of other FHR abnormalities. FHR abnormalities other than tachycardia were excluded from the analysis. The primary outcome was a perinatal composite (5-minute Apgar's score ≤3, intubation, chest compressions, or mortality). Secondary outcomes included low arterial cord pH (pH < 7.20), base deficit ≥12, and cesarean delivery.

RESULTS

 A total of 986 (18.5%) of women in the trial developed intrapartum fever, and 728 (13.7%) met criteria to be analyzed; of these, 728 women 336 (46.2%) had maternal-fetal medicine (MFM) reviewer-defined fetal tachycardia, and 349 of the 550 (63.5%) women during the final hour of labor had validated software (PeriCALM) defined fetal tachycardia. After adjusting for confounders, isolated fetal tachycardia was not associated with a significant difference in the composite perinatal outcome (adjusted odds ratio [aOR] = 3.15 [0.82-12.03]) compared with absence of tachycardia. Fetal tachycardia was associated with higher odds of arterial cord pH <7.2, aOR = 1.48 (1.01-2.17) and of infants with a base deficit ≥ 12, aOR = 2.42 (1.02-5.77), but no significant difference in the odds of cesarean delivery, aOR = 1.33 (0.97-1.82).

CONCLUSION

 Fetal tachycardia in the setting of intrapartum fever or chorioamnionitis is associated with significantly increased fetal acidemia defined as a pH <7.2 and base excess ≥12 but not with a composite perinatal morbidity.

KEY POINTS

· The perinatal outcomes associated with fetal tachycardia in the setting of maternal fever are undefined.. · Fetal tachycardia was not significantly associated with perinatal morbidity although the sample size was limited.. · Fetal tachycardia was associated with an arterial cord pH <7.2 and base deficit of 12 or greater..

Genetic Predisposition to Adverse Neurodevelopmental Outcome of Extremely Low Birth Weight Infants

OBJECTIVE

 This study aimed to evaluate whether there are genetic variants associated with adverse neurodevelopmental outcomes in extremely low birth weight (ELBW) infants.

STUDY DESIGN

 We conducted a candidate gene association study in two well-defined cohorts of ELBW infants (<1,000 g). One cohort was for discovery and the other for replication. The discovery case-control analysis utilized anonymized DNA samples and evaluated 1,614 single-nucleotide polymorphisms (SNPs) in 145 genes concentrated in inflammation, angiogenesis, brain development, and oxidation pathways. Cases were children who died by age one or who were diagnosed with cerebral palsy (CP) or neurodevelopmental delay (Bayley II mental developmental index [MDI] or psychomotor developmental index [PDI] < 70) by 18 to 22 months. Controls were survivors with normal neurodevelopment. We assessed significant epidemiological variables and SNPs associated with the combined outcome of CP or death, CP, mental delay (MDI < 70) and motor delay (PDI < 70). Multivariable analyses adjusted for gestational age at birth, small for gestational age, sex, antenatal corticosteroids, multiple gestation, racial admixture, and multiple comparisons. SNPs associated with adverse neurodevelopmental outcomes with p < 0.01 were selected for validation in the replication cohort. Successful replication was defined as p < 0.05 in the replication cohort.

RESULTS

 Of 1,013 infants analyzed (452 cases, 561 controls) in the discovery cohort, 917 were successfully genotyped for >90% of SNPs and passed quality metrics. After adjusting for covariates, 26 SNPs with p < 0.01 for one or more outcomes were selected for replication cohort validation, which included 362 infants (170 cases and 192 controls). A variant in SERPINE1, which encodes plasminogen activator inhibitor (PAI1), was associated with the combined outcome of CP or death in the discovery analysis (p = 4.1 × 10-4) and was significantly associated with CP or death in the replication cohort (adjusted odd ratio: 0.4; 95% confidence interval: 0.2-1.0; p = 0.039).

CONCLUSION

 A genetic variant in SERPINE1, involved in inflammation and coagulation, is associated with CP or death among ELBW infants.

KEY POINTS

· Early preterm and ELBW infants have dramatically increased risks of CP and developmental delay.. · A genetic variant in SERPINE1 is associated with CP or death among ELBW infants.. · The SERPINE1 gene encodes the serine protease inhibitor plasminogen activator inhibitor..

Risk of Ischemic Placental Disease in Relation to Family History of Preeclampsia

OBJECTIVE

To assess the risk of ischemic placental disease (IPD) including preeclampsia, small for gestational age (SGA), and abruption, in relation to preeclampsia in maternal grandmother, mother, and sister(s).

STUDY DESIGN

We performed a secondary analysis of data from a randomized trial of vitamins C and E for preeclampsia prevention. Data on family history of preeclampsia were based on recall by the proband. The associations between family history of preeclampsia and the odds of IPD were evaluated from alternating logistic regressions.

RESULTS

Of the 9,686 women who delivered nonmalformed, singleton live births, 17.1% had IPD. Probands provided data on preeclampsia in 55.5% (n = 5,374) on all three family members, 26.5% (n = 2,562) in mother and sister(s) only, and 11.6% (n = 1,125) in sister(s) only. The pairwise odds ratio (pOR) of IPD was 1.16 (95% confidence interval [CI]: 1.00-1.36) if one or more of the female relatives had preeclampsia. The pORs of preeclampsia were 1.54 (95% CI: 1.12-2.13) and 1.35 (95% CI: 1.03-1.77) if the proband's mother or sister(s) had a preeclamptic pregnancy, respectively, but no associations were seen for SGA infant or abruption.

CONCLUSION

This study suggests that IPD may share a predisposition with preeclampsia, suggesting a familial inheritance.

Cord Blood Haptoglobin, Cerebral Palsy and Death in Infants of Women at Risk for Preterm Birth: A Secondary Analysis of a Randomised Controlled Trial

BACKGROUND

Antenatal exposure to intra-uterine inflammation results in precocious Haptoglobin (Hp) expression (switch-on status). We investigated the relationships between foetal Hp expression at birth with newborn and childhood outcomes.

METHODS

We evaluated cord blood samples from 921 newborns of women at imminent risk for preterm delivery randomised to either placebo (n = 471, birth gestational age (GA) median [min-max]: 31 [24-41] weeks) or magnesium sulphate (n = 450, GA 31 [24-42] weeks]). Primary outcome was infant death by 1 year and/or cerebral palsy (CP) ≥ 2 years of corrected age. Adjusted odd ratios (aOR) for neonatal and childhood outcomes were calculated controlling for GA, birth weight, sex, and magnesium exposure.

FINDINGS

Primary outcome occurred in 2.8% of offspring. Newborns were classified in three pre-defined categorisation groups by cord blood Hp switch status and IL-6 levels: inflammation-nonexposed (Category 1, n = 432, 47%), inflammation-exposed haptoglobinemic (Category 2, n = 449, 49%), and inflammation-exposed anhaptoglobinemic or hypohaptoglobinemic (Category 3, n = 40, 4%). Newborns, found anhaptoglobinemic or hypohaptoglobinemic (Category 3) had increased OR for intraventricular haemorrhage (IVH) and/or death (aOR: 7.0; 95% CI: 1.4-34.6, p = 0.02) and for CP and/or death (aOR: 6.27; 95% CI: 1.7-23.5, p = 0.006) compared with Category 2. Foetal ability to respond to inflammation by haptoglobinemia resulted in aOR similar to inflammation-nonexposed newborns. Hp1-2 or Hp2-2 phenotypes protected against retinopathy of prematurity (aOR = 0.66; 95% CI 0.48-0.91, p = 0.01).

INTERPRETATION

Foetal ability to switch-on Hp expression in response to inflammation was associated with reduction of IVH and/or death, and CP and/or death. Foetuses unable to mount such a response had an increased risk of adverse outcomes.Trial Registration: clinicaltrials.gov Identifier: NCT00014989.

Incidence of early-onset sepsis in infants born to women with clinical chorioamnionitis

Objective To determine the frequency of sepsis and other adverse neonatal outcomes in women with a clinical diagnosis of chorioamnionitis. Methods We performed a secondary analysis of a multi-center placebo-controlled trial of vitamins C/E to prevent preeclampsia in low risk nulliparous women. Clinical chorioamnionitis was defined as either the "clinical diagnosis" of chorioamnionitis or antibiotic administration during labor because of an elevated temperature or uterine tenderness in the absence of another cause. Early-onset neonatal sepsis was categorized as "suspected" or "confirmed" based on a clinical diagnosis with negative or positive blood, urine or cerebral spinal fluid cultures, respectively, within 72 h of birth. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by logistic regression. Results Data from 9391 mother-infant pairs were analyzed. The frequency of chorioamnionitis was 10.3%. Overall, 6.6% of the neonates were diagnosed with confirmed (0.2%) or suspected (6.4%) early-onset sepsis. Only 0.7% of infants born in the setting of chorioamnionitis had culture-proven early-onset sepsis versus 0.1% if chorioamnionitis was not present. Clinical chorioamnionitis was associated with both suspected [OR 4.01 (3.16-5.08)] and confirmed [OR 4.93 (1.65-14.74)] early-onset neonatal sepsis, a need for resuscitation within the first 30 min after birth [OR 2.10 (1.70-2.61)], respiratory distress [OR 3.14 (2.16-4.56)], 1 min Apgar score of ≤3 [OR 2.69 (2.01-3.60)] and 4-7 [OR 1.71 (1.43-2.04)] and 5 min Apgar score of 4-7 [OR 1.67 (1.17-2.37)] (vs. 8-10). Conclusion Clinical chorioamnionitis is common and is associated with neonatal morbidities. However, the vast majority of exposed infants (99.3%) do not have confirmed early-onset sepsis.

Adverse Maternal and Neonatal Outcomes in Indicated Compared with Spontaneous Preterm Birth in Healthy Nulliparas: A Secondary Analysis of a Randomized Trial

OBJECTIVE

To compare the risks of adverse maternal and neonatal outcomes associated with spontaneous (SPTB) versus indicated preterm births (IPTB).

METHODS

A secondary analysis of a multicenter trial of vitamin C and E supplementation in healthy low-risk nulliparous women. Outcomes were compared between women with SPTB (due to spontaneous membrane rupture or labor) and those with IPTB (due to medical or obstetric complications). A primary maternal composite outcome included: death, pulmonary edema, blood transfusion, adult respiratory distress syndrome (RDS), cerebrovascular accident, acute tubular necrosis, disseminated intravascular coagulopathy, or liver rupture. A neonatal composite outcome included: neonatal death, RDS, grades III or IV intraventricular hemorrhage (IVH), sepsis, necrotizing enterocolitis (NEC), or retinopathy of prematurity.

RESULTS

Of 9,867 women, 10.4% (N = 1,038) were PTBs; 32.7% (n = 340) IPTBs and 67.3% (n = 698) SPTBs. Compared with SPTB, the composite maternal outcome was more frequent in IPTB-4.4% versus 0.9% (adjusted odds ratio [aOR], 4.0; 95% confidence interval [CI], 1.4-11.8), as were blood transfusion and prolonged hospital stay (3.2 and 3.7 times, respectively). The frequency of composite neonatal outcome was higher in IPTBs (aOR, 1.8; 95% CI, 1.1-3.0), as were RDS (1.7 times), small for gestational age (SGA) < 5th percentile (7.9 times), and neonatal intensive care unit (NICU) admission (1.8 times).

CONCLUSION

Adverse maternal and neonatal outcomes were significantly more likely with IPTB than with SPTB.

The association among cytochrome P450 3A, progesterone receptor polymorphisms, plasma 17-alpha hydroxyprogesterone caproate concentrations, and spontaneous preterm birth

BACKGROUND

Infants born <37 weeks' gestation are of public health concern since complications associated with preterm birth are the leading cause of mortality in children <5 years of age and a major cause of morbidity and lifelong disability. The administration of 17-alpha hydroxyprogesterone caproate reduces preterm birth by 33% in women with history of spontaneous preterm birth. We demonstrated previously that plasma concentrations of 17-alpha hydroxyprogesterone caproate vary widely among pregnant women and that women with 17-alpha hydroxyprogesterone caproate plasma concentrations in the lowest quartile had spontaneous preterm birth rates of 40% vs rates of 25% in those women with higher concentrations. Thus, plasma concentrations are an important factor in determining drug efficacy but the reason 17-alpha hydroxyprogesterone caproate plasma concentrations vary so much is unclear. Predominantly, 17-alpha hydroxyprogesterone caproate is metabolized by CYP3A4 and CYP3A5 enzymes.

OBJECTIVE

We sought to: (1) determine the relation between 17-alpha hydroxyprogesterone caproate plasma concentrations and single nucleotide polymorphisms in CYP3A4 and CYP3A5; (2) test the association between progesterone receptor single nucleotide polymorphisms and spontaneous preterm birth; and (3) test whether the association between plasma concentrations of 17-alpha hydroxyprogesterone caproate and spontaneous preterm birth varied by progesterone receptor single nucleotide polymorphisms.

STUDY DESIGN

In this secondary analysis, we evaluated genetic polymorphism in 268 pregnant women treated with 17-alpha hydroxyprogesterone caproate, who participated in a placebo-controlled trial to evaluate the benefit of omega-3 supplementation in women with history of spontaneous preterm birth. Trough plasma concentrations of 17-alpha hydroxyprogesterone caproate were measured between 25-28 weeks of gestation after a minimum of 5 injections of 17-alpha hydroxyprogesterone caproate. We extracted DNA from maternal blood samples and genotyped the samples using TaqMan (Applied Biosystems, Foster City, CA) single nucleotide polymorphism genotyping assays for the following single nucleotide polymorphisms: CYP3A4*1B, CYP3A4*1G, CYP3A4*22, and CYP3A5*3; and rs578029, rs471767, rs666553, rs503362, and rs500760 for progesteronereceptor. We adjusted for prepregnancy body mass index, race, and treatment group in a multivariable analysis. Differences in the plasma concentrations of 17-alpha hydroxyprogesterone caproate by genotype were evaluated for each CYP single nucleotide polymorphism using general linear models. The association between progesterone receptor single nucleotide polymorphisms and frequency of spontaneous preterm birth was tested using logistic regression. A logistic model also tested interaction between 17-alpha hydroxyprogesterone caproate concentrations with each progesterone receptor single nucleotide polymorphism for the outcome of spontaneous preterm birth.

RESULTS

The association between CYP single nucleotide polymorphisms *22, *1G, *1B, and *3 and trough plasma concentrations of 17-alpha hydroxyprogesterone caproate was not statistically significant (P = .68, .44, .08, and .44, respectively). In an adjusted logistic regression model, progesterone receptor single nucleotide polymorphisms rs578029, rs471767, rs666553, rs503362, and rs500760 were not associated with the frequency of spontaneous preterm birth (P = .29, .10, .76, .09, and .43, respectively). Low trough plasma concentrations of 17-alpha hydroxyprogesterone caproate were statistically associated with a higher frequency of spontaneous preterm birth (odds ratio, 0.78; 95% confidence ratio, 0.61-0.99; P = .04 for trend across quartiles), however no significant interaction with the progesterone receptor single nucleotide polymorphisms rs578029, rs471767, rs666553, rs503362, and rs500760 was observed (P = .13, .08, .10, .08, and .13, respectively).

CONCLUSION

The frequency of recurrent spontaneous preterm birth appears to be associated with trough 17-alpha hydroxyprogesterone caproate plasma concentrations. However, the wide variation in trough 17-alpha hydroxyprogesterone caproate plasma concentrations is not attributable to polymorphisms in CYP3A4 and CYP3A5 genes. Progesterone receptor polymorphisms do not predict efficacy of 17-alpha hydroxyprogesterone caproate. The limitations of this secondary analysis include that we had a relative small sample size (n = 268) and race was self-reported by the patients.

Antenatal Magnesium and Cerebral Palsy in Preterm Infants

OBJECTIVE

To evaluate the relationship of maternal antenatal magnesium sulfate (MgSO4) with neonatal cranial ultrasound abnormalities and cerebral palsy (CP).

STUDY DESIGN

In a randomized trial of MgSO4 or placebo in women at high risk of preterm delivery, up to 3 cranial ultrasounds were obtained in the neonatal period. Images were reviewed by at least 2 pediatric radiologists masked to treatment and other clinical conditions. Diagnoses were predefined for intraventricular hemorrhage, periventricular leukomalacia, intracerebral echolucency or echodensity, and ventriculomegaly. CP was diagnosed at 2 years of age by standardized neurologic examination.

RESULTS

Intraventricular hemorrhage, periventricular leukomalacia, intracerebral echolucency or echodensity, and ventriculomegaly were all strongly associated with an increased risk of CP. MgSO4 administration did not affect the risk of cranial ultrasound abnormality observed at 35 weeks postmenstrual age or later. However, for the 82% of infants born at <32 weeks gestation, MgSO4 was associated with a reduction in risk of echolucency or echodensity. The reduction in risk for echolucency explained 21% of the effect of MgSO4 on CP (P = .04), and for echodensity explained 20% of the effect (P = .02).

CONCLUSIONS

MgSO4 given prior to preterm delivery was associated with decreased risk of developing echodensities and echolucencies at <32 weeks gestation. However, this effect can only partially explain the effect of MgSO4 on CP at 2 years of age.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00014989.

Relation between birth weight and weight and height at the age of 2 in children born preterm

OBJECTIVE

The aim of the study was to evaluate associations between fetal growth and weight at 2 years in infants born preterm using a customized approach for birth weight.

STUDY DESIGN

This is a secondary analysis of a multicenter trial that included a 2-year follow-up of children born prematurely. Customized birth weight percentiles were calculated using the Gardosi model for a U.S. population, and the relation between customized percentile and weight and height at 2 years (adjusted for gender using z-score) was determined using regression analysis and by comparing z-scores for children with birth weight <10th versus ≥10th percentile.

RESULTS

Weight z-score at 2 years was significantly lower in the <10th than in the ≥10th percentile group (median [interquartile range, IQR]: -0.66 [-1.58, -0.01] vs. -0.23 [-1.05, 0.55]; p < 0.001), and remained after adjusting for maternal education (p < 0.001). A similar relationship was noted for height z-score between groups (median [IQR]: -0.56 [-1.29, 0.19] vs. -0.24 [-0.99, 0.37]; p < 0.001). Positive relationships between customized birth weight percentile and weight and height at 2 years were noted (p < 0.001 for both), but were not strong (R (2) = 0.04 and 0.02, respectively).

CONCLUSION

Customized birth weight percentile is a minor determinant of weight at 2 years among children born preterm.

Accuracy of sonographic chorionicity classification in twin gestations

OBJECTIVES

To evaluate the accuracy of sonographic classification of chorionicity in a large cohort of twins and investigate which factors may be associated with sonographic accuracy.

METHODS

We conducted a secondary analysis of a randomized trial of preterm birth prevention in twins. Sonographic classification of chorionicity was compared with pathologic examination of the placenta. Maternal (age, body mass index, diabetes, and hypertension), obstetric (prior cesarean delivery, gestational age at the first sonographic examination, and antepartum bleeding), and sonographic (oligohydramnios, polyhydramnios, and twin-twin transfusion syndrome) factors were assessed for their possible association with accuracy.

RESULTS

A total of 545 twin sets in which chorionicity was classified by sonography before 20 weeks' gestation were included; 455 were dichorionic and 90 were monochorionic based on pathologic examination. Sonography misclassified 35 of 545 twin pregnancies (6.4%): 18 of 455 dichorionic twins (4.0%) and 17 of 90 monochorionic twins (19.0%). The sensitivity and specificity of sonographic diagnosis of monochorionicity were 81.1% and 96.0%, respectively. In a multivariable analysis, pregnancies with initial sonographic examinations before 14 weeks' gestation were less likely to have misclassified chorionicity than those with sonographic examinations at 15 to 20 weeks (odds ratio [OR], 0.47; 95% confidence interval [CI], 0.23-0.96). For each week increase in gestational age, the odds of misclassification rose by 10% (OR, 1.10; 95% CI, 1.01-1.2). In the multivariable analysis, maternal age, body mass index, parity, and prior cesarean delivery were not associated with sonographic accuracy.

CONCLUSIONS

Sonography before 20 weeks incorrectly classified chorionicity in 6.4% of twin gestations. Those with first sonographic examinations performed at earlier gestational ages had improved chorionicity diagnosis.

Relationship between 17-alpha hydroxyprogesterone caproate concentration and spontaneous preterm birth

OBJECTIVE

17-alpha hydroxyprogesterone caproate 250 mg weekly reduces recurrent spontaneous preterm birth in women with a prior spontaneous preterm birth by 33%. The dose is not based on pharmacologic considerations. A therapeutic concentration has not been determined hampering any attempt to optimize treatment. This study evaluated the relationship between 17-alpha hydroxyprogesterone caproate plasma concentrations and the rate of spontaneous preterm birth in women with singleton gestation.

STUDY DESIGN

A single blood sample was obtained between 25 and 28 weeks' gestation from 315 women with a spontaneous preterm birth who participated in a placebo-controlled, prospective, randomized clinical trial evaluating the benefit of omega-3 supplementation in reducing preterm birth. All women in the parent study received 17-alpha hydroxyprogesterone caproate and 434 received omega-3 supplementation and 418 received a placebo. Plasma from 315 consenting women was analyzed for 17-alpha hydroxyprogesterone caproate concentration.

RESULTS

There were no differences between placebo and omega-3 supplemented groups in demographic variables, outcomes or in mean 17-alpha hydroxyprogesterone caproate concentration. Plasma concentrations of 17-alpha hydroxyprogesterone caproate ranged from 3.7-56 ng/mL. Women with plasma concentrations of 17-alpha hydroxyprogesterone caproate in the lowest quartile had a significantly higher risk of spontaneous preterm birth (P = .03) and delivered at significantly earlier gestational ages (P = .002) than did women in the second to fourth quartiles. The lowest preterm birth rates were seen when median 17-alpha hydroxyprogesterone caproate concentrations exceeded 6.4 ng/mL.

CONCLUSION

Low plasma 17-alpha hydroxyprogesterone caproate concentration is associated with an increased risk of spontaneous preterm birth. This finding validates efficacy of this treatment but suggests that additional studies are needed to determine the optimal dosage.

Maternal 25-hydroxyvitamin d and preterm birth in twin gestations

OBJECTIVE

To assess whether there was an independent association between maternal 25-hydroxyvitamin D concentrations at 24-28 weeks of gestation and preterm birth in a multicenter U.S. cohort of twin pregnancies.

METHODS

Serum samples from women who participated in a clinical trial of 17 α-hydroxyprogesterone caproate for the prevention of preterm birth in twin gestations (2004-2006) were assayed for 25-hydroxyvitamin D concentrations using liquid chromatography tandem mass spectrometry (n=211). Gestational age was determined early in pregnancy using a rigorous algorithm. Preterm birth was defined as delivery of the first twin or death of either twin at less than 35 weeks of gestation.

RESULTS

The mean serum 25-hydroxyvitamin D concentration was 82.7 nmol/L (standard deviation 31.5); 40.3% of women had concentrations less than 75 nmol/L. Preterm birth at less than 35 weeks of gestation occurred in 49.4% of women with 25-hydroxyvitamin D concentrations less than 75 nmol/L compared with 26.2% among those with concentrations of 75 nmol/L or more (P<.001). After adjustment for maternal race and ethnicity, study site, parity, prepregnancy body mass index, season, marital status, education, gestational age at blood sampling, smoking status, and 17 α-hydroxyprogesterone caproate treatment, maternal 25-hydroxyvitamin D concentration of 75 nmol/L or more was associated with a 60% reduction in the odds of preterm birth compared with concentrations less than 75 nmol/L (adjusted odds ratio [OR] 0.4, 95% confidence interval [CI] 0.2-0.8). A similar protective association was observed when studying preterm birth at less than 32 weeks of gestation (OR 0.2, 95% CI 0.1-0.6) and after confounder adjustment.

CONCLUSIONS

Late second-trimester maternal 25-hydroxyvitamin D concentrations less than 75 nmol/L are associated with an increase in the risk of preterm birth in this cohort of twin pregnancies.

LEVEL OF EVIDENCE

II.

Haptoglobin phenotype, preeclampsia risk and the efficacy of vitamin C and E supplementation to prevent preeclampsia in a racially diverse population

Haptoglobin's (Hp) antioxidant and pro-angiogenic properties differ between the 1-1, 2-1, and 2-2 phenotypes. Hp phenotype affects cardiovascular disease risk and treatment response to antioxidant vitamins in some non-pregnant populations. We previously demonstrated that preeclampsia risk was doubled in white Hp 2-1 women, compared to Hp 1-1 women. Our objectives were to determine whether we could reproduce this finding in a larger cohort, and to determine whether Hp phenotype influences lack of efficacy of antioxidant vitamins in preventing preeclampsia and serious complications of pregnancy-associated hypertension (PAH). This is a secondary analysis of a randomized controlled trial in which 10,154 low-risk women received daily vitamin C and E, or placebo, from 9-16 weeks gestation until delivery. Hp phenotype was determined in the study prediction cohort (n = 2,393) and a case-control cohort (703 cases, 1,406 controls). The primary outcome was severe PAH, or mild or severe PAH with elevated liver enzymes, elevated serum creatinine, thrombocytopenia, eclampsia, fetal growth restriction, medically indicated preterm birth or perinatal death. Preeclampsia was a secondary outcome. Odds ratios were estimated by logistic regression. Sampling weights were used to reduce bias from an overrepresentation of women with preeclampsia or the primary outcome. There was no relationship between Hp phenotype and the primary outcome or preeclampsia in Hispanic, white/other or black women. Vitamin supplementation did not reduce the risk of the primary outcome or preeclampsia in women of any phenotype. Supplementation increased preeclampsia risk (odds ratio 3.30; 95% confidence interval 1.61-6.82, p<0.01) in Hispanic Hp 2-2 women. Hp phenotype does not influence preeclampsia risk, or identify a subset of women who may benefit from vitamin C and E supplementation to prevent preeclampsia.

Can changes in angiogenic biomarkers between the first and second trimesters of pregnancy predict development of pre-eclampsia in a low-risk nulliparous patient population?

OBJECTIVE

To determine if change in maternal angiogenic biomarkers between the first and second trimesters predicts pre-eclampsia in low-risk nulliparous women.

DESIGN

A nested case-control study of change in maternal plasma soluble Flt-1 (sFlt-1), soluble endoglin (sEng) and placenta growth factor (PlGF). We studied 158 pregnancies complicated by pre-eclampsia and 468 normotensive nonproteinuric controls.

SETTING

A multicentre study in 16 academic medical centres in the USA.

POPULATION

Low-risk nulliparous women.

METHODS

Luminex assays for PlGF, sFlt-1 and sEng performed on maternal EDTA plasma collected at 9-12, 15-18 and 23-26 weeks of gestation. Rate of change of analyte between first and either early or late second trimester was calculated with and without adjustment for baseline clinical characteristics.

MAIN OUTCOME MEASURES

Change in PlGF, sFlt-1 and sEng.

RESULTS

Rates of change of PlGF, sEng and sFlt-1 between first and either early or late second trimesters were significantly different in women who developed pre-eclampsia, severe pre-eclampsia or early-onset pre-eclampsia compared with women who remained normotensive. Inclusion of clinical characteristics (race, body mass index and blood pressure at entry) increased sensitivity for detecting severe and particularly early-onset pre-eclampsia but not pre-eclampsia overall. Receiver operating characteristics curves for change from first to early second trimester in sEng, PlGF and sFlt-1 with clinical characteristics had areas under the curve of 0.88, 0.84 and 0.86, respectively, and for early-onset pre-eclampsia with sensitivities of 88% (95% CI 64-99), 77% (95% CI 50-93) and 77% (95% CI 50-93) for 80% specificity, respectively. Similar results were seen in the change from first to late second trimester.

CONCLUSION

Change in angiogenic biomarkers between first and early second trimester combined with clinical characteristics has strong utility for predicting early-onset pre-eclampsia.

Vitamin D status and recurrent preterm birth: a nested case-control study in high-risk women

OBJECTIVE

To determine whether vitamin D status is associated with recurrent preterm birth, and any interactions between vitamin D levels and fish consumption.

DESIGN

A nested case-control study, using data from a randomised trial of omega-3 fatty acid supplementation to prevent recurrent preterm birth.

SETTING

Fourteen academic health centres in the USA.

POPULATION

Women with prior spontaneous preterm birth.

METHODS

In 131 cases (preterm delivery at <35 weeks of gestation) and 134 term controls, we measured serum 25-hydroxyvitamin D [25(OH)D] concentrations by liquid chromatography-tandem mass spectrometry (LC-MS) from samples collected at baseline (16-22 weeks of gestation). Logistic regression models controlled for study centre, maternal age, race/ethnicity, number of prior preterm deliveries, smoking status, body mass index, and treatment.

MAIN OUTCOME MEASURES

Recurrent preterm birth at <37 and <32 weeks of gestation.

RESULTS

The median mid-gestation serum 25(OH)D concentration was 67 nmol/l, and 27% had concentrations of <50 nmol/l. Serum 25(OH)D concentration was not significantly associated with preterm birth (OR 1.33; 95% CI 0.48-3.70 for lowest versus highest quartiles). Likewise, comparing women with 25(OH)D concentrations of 50 nmol/l, or higher, with those with <50 nmol/l generated an odds ratio of 0.80 (95% CI 0.38-1.69). Contrary to our expectation, a negative correlation was observed between fish consumption and serum 25(OH)D concentration (-0.18, P < 0.01).

CONCLUSIONS

In a cohort of women with a prior preterm birth, vitamin D status at mid-pregnancy was not associated with recurrent preterm birth.

Fetal male gender and the benefits of treatment of mild gestational diabetes mellitus

OBJECTIVE

We evaluated whether improvements in pregnancy outcomes after treatment of mild gestational diabetes mellitus differed in magnitude on the basis of fetal gender.

STUDY DESIGN

This is a secondary analysis of a masked randomized controlled trial of treatment for mild gestational diabetes mellitus. The results included preeclampsia or gestational hypertension, birthweight, neonatal fat mass, and composite adverse outcomes for both neonate (preterm birth, small for gestational age, or neonatal intensive care unit admission) and mother (labor induction, cesarean delivery, preeclampsia, or gestational hypertension). After stratification according to fetal gender, the interaction of gender with treatment status was estimated for these outcomes.

RESULTS

Of the 469 pregnancies with male fetuses, 244 pregnancies were assigned randomly to treatment, and 225 pregnancies were assigned randomly to routine care. Of the 463 pregnancies with female fetuses, 233 pregnancies were assigned randomly to treatment, and 230 pregnancies were assigned randomly to routine care. The interaction of gender with treatment status was significant for fat mass (P = .04) and birthweight percentile (P = .02). Among women who were assigned to the treatment group, male offspring were significantly more likely to have both a lower birthweight percentile (50.7 ± 29.2 vs 62.5 ± 30.2 percentile; P < .0001) and less neonatal fat mass (487 ± 229.6 g vs 416.6 ± 172.8 g; P = .0005,) whereas these differences were not significant among female offspring. There was no interaction between fetal gender and treatment group with regard to other outcomes.

CONCLUSION

The magnitude of the reduction of a newborn's birthweight percentile and neonatal fat mass that were related to the treatment of mild gestational diabetes mellitus appears greater for male neonates.

Timing of delivery and pregnancy outcomes among laboring nulliparous women

OBJECTIVE

The objective of the study was to compare pregnancy outcomes by completed week of gestation after 39 weeks with outcomes at 39 weeks.

STUDY DESIGN

Secondary analysis of a multicenter trial of fetal pulse oximetry in spontaneously laboring or induced nulliparous women at a gestation of 36 weeks or longer. Maternal outcomes included a composite (treated uterine atony, blood transfusion, and peripartum infections) and cesarean delivery. Neonatal outcomes included a composite of death, neonatal respiratory and other morbidities, and neonatal intensive care unit admission.

RESULTS

Among the 4086 women studied, the risks of the composite maternal outcome (P value for trend < .001), cesarean delivery (P < .001), and composite neonatal outcome (P = .047) increased with increasing gestational age from 39 to 41 or more completed weeks. Adjusted odds ratios (95% confidence interval) for 40 and 41 or more weeks, respectively, compared with 39 weeks were 1.29 (1.03-1.64) and 2.05 (1.60-2.64) for composite maternal outcome, 1.28 (1.05-1.57) and 1.75 (1.41-2.16) for cesarean delivery, and 1.25 (0.86-1.83) and 1.37 (0.90-2.09) for composite neonatal outcome.

CONCLUSION

Risks of maternal morbidity and cesarean delivery but not neonatal morbidity increased significantly beyond 39 weeks.

The stillbirth collaborative research network postmortem examination protocol

After reviewing the state of knowledge about the scope and causes of stillbirth (SB) in a special workshop sponsored by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), the participants determined that there is little guidance regarding the best use of postmortem examination (PM) to address the pathogenesis of stillbirth. In this report, we describe the PM procedure designed and used in the NICHD-supported Stillbirth Cooperative Research Network (SCRN). Perinatal pathologists, clinicians, epidemiologists, and biostatisticians at four tertiary care centers, a data coordinating center, and NICHD developed a standardized approach to perinatal PM, which was applied to a population-based study of stillbirth as part of the SCRN. The SCRN PM protocol was successfully instituted and used at the four medical centers. A total of 663 women with stillbirth were included: 620 delivered a single stillborn infant, 42 delivered twins, and one delivered triplets for a total of 676 stillborn infants. Of these women, 560 (84.5%) consented to PM (572 stillborn infants) that was conducted according to the SCRN protocol. A standardized PM protocol was developed to evaluate stillbirth consistently across centers in the United States. Novel testing and approaches that increase the yield of the PM can be developed using this model.

Fish consumption, erythrocyte fatty acids, and preterm birth

OBJECTIVE

To estimate the association between fish consumption and erythrocyte omega-3 long-chain polyunsaturated fatty acids and preterm birth in a high-risk cohort.

METHODS

This was an ancillary study to a randomized trial of omega-3 supplementation to prevent preterm birth in women with at least one previous spontaneous preterm delivery. Dietary fish intake was assessed by questionnaire and erythrocyte fatty acids were measured at enrollment (16-21 completed weeks of gestation). The association between fish consumption and preterm delivery was modeled with linear and quadratic terms.

RESULTS

The probability of preterm birth was 48.6% among women eating fish less than once a month and 35.9% among women eating fish more often (P<.001). The adjusted odds ratio for preterm birth among women reporting moderately frequent fish consumption (three servings per week) was 0.60 (95% confidence interval 0.38-0.95), with no further reduction in preterm birth among women who consumed more than three servings of fish per week. Erythrocyte omega-3 levels correlated weakly but significantly with frequency of fish intake (Spearman r=0.22, P<.001); women in the lowest quartile of erythrocyte omega-3 levels were more likely to report consuming less than one fish meal per month (40.3%) than were women in the highest three quartiles (26.3%, P<.001).

CONCLUSION

Moderate fish intake (up to three meals per week) before 22 weeks of gestation was associated with a reduction in repeat preterm birth. More than moderate consumption did not confer additional benefit. These results support the recommendations of the U.S. Food and Drug Administration and the American Congress of Obstetricians and Gynecologists for fish consumption during pregnancy.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, www.clinicaltrials.gov, NCT00135902.

Maternal insulin resistance and preeclampsia

OBJECTIVE

The purpose of this study was to determine whether mid-trimester insulin resistance is associated with subsequent preeclampsia.

STUDY DESIGN

This was a secondary analysis of 10,154 nulliparous women who received vitamin C and E or placebo daily from 9-16 weeks gestation until delivery. Of these, 1187 women had fasting plasma glucose and insulin tested between 22 and 26 weeks gestation. Insulin resistance was calculated by the homeostasis model assessment of insulin resistance (HOMA-IR) and the quantitative insulin sensitivity check index.

RESULTS

Obese women were twice as likely to have a HOMA-IR result of ≥75th percentile. Hispanic and African American women had a higher percentage at ≥75th percentile for HOMA-IR than white women (42.2%, 27.2%, and 16.9%, respectively; P < .001). A HOMA-IR result of ≥75th percentile was higher among the 85 nulliparous women who subsequently had preeclampsia, compared with women who remained normotensive (40.5% vs 24.8%; adjusted odds ratio, 1.9; 95% confidence interval, 1.1-3.2). Quantitative insulin sensitivity check index results were similar to the HOMA-IR results.

CONCLUSION

Midtrimester maternal insulin resistance is associated with subsequent preeclampsia.

Maternal serum interleukin-6, C-reactive protein, and matrix metalloproteinase-9 concentrations as risk factors for preterm birth <32 weeks and adverse neonatal outcomes

Elevated concentrations of interleukin-6 (IL-6), C-reactive protein (CRP), and matrix metalloproteinase-9 (MMP-9) in fetal and neonatal compartments have been associated with an increased risk for preterm birth (PTB) and/or neonatal morbidity. The purpose of this study was to determine if the maternal serum concentration of IL-6, CRP, and MMP-9 in women at risk for PTB, who are not in labor and have intact membranes, are associated with an increased risk for PTB <32 weeks and/or neonatal morbidity. Maternal serum samples collected from 475 patients enrolled in a multicenter randomized controlled trial of single versus weekly corticosteroids for women at increased risk for preterm delivery were assayed. Serum was collected at randomization (24 to 32 weeks' gestation). Maternal serum concentrations of IL-6, CRP, and MMP-9 were subsequently determined using enzyme-linked immunoassays. Multivariate logistic regression analysis was performed to explore the relationship between maternal serum concentrations of IL-6, CRP, and MMP-9 and PTB <32 weeks, respiratory distress syndrome (RDS), chronic lung disease (CLD), intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), and any sepsis. Maternal serum concentrations of IL-6 and CRP, but not MMP-9, above the 90th percentile at the time of randomization were associated with PTB <32 weeks. In contrast, there was no significant relationship between RDS and NEC and the maternal serum concentration of IL-6, CRP, or MMP-9 (univariate analysis). The development of CLD was associated with a high (above 90th percentile) IL-6 and CRP in maternal serum, even after adjustment for gestational age (GA) at randomization and treatment group. However, when GA at delivery was added to the model, this finding was nonsignificant. Neonatal sepsis was more frequent in neonates born to mothers with a high maternal serum concentration of CRP (>90th percentile). However, there was no significant association after adjustment for GA at randomization and treatment group. Logistic regression analysis for each analyte indicated that high maternal serum concentrations of IL-6 and CRP, but not MMP-9, were associated with an increased risk of IVH (odds ratio [OR] 4.60, 95% confidence interval [CI] 1.86 to 10.68; OR 4.07, 95% CI 1.63 to 9.50) after adjusting for GA at randomization and treatment group. Most babies (25/30) had grade I IVH. When GA at delivery was included, elevated IL-6 remained significantly associated with IVH (OR 2.77, 95% CI 1.02 to 7.09). An elevated maternal serum concentration of IL-6 and CRP are risk factors for PTB <32 weeks and subsequent development of neonatal IVH. An elevated maternal serum IL-6 appears to confer additional risk for IVH even after adjusting for GA at delivery.

Neonatal outcomes and operative vaginal delivery versus cesarean delivery

We compared outcomes for neonates with forceps-assisted, vacuum-assisted, or cesarean delivery in the second stage of labor. This is a secondary analysis of a randomized trial in laboring, low-risk, nulliparous women at >or=36 weeks' gestation. Neonatal outcomes after use of forceps, vacuum, and cesarean were compared among women in the second stage of labor at station +1 or below (thirds scale) for failure of descent or nonreassuring fetal status. Nine hundred ninety women were included in this analysis: 549 (55%) with an indication for delivery of failure of descent and 441 (45%) for a nonreassuring fetal status. Umbilical cord gases were available for 87% of neonates. We found no differences in the base excess (P = 0.35 and 0.78 for failure of descent and nonreassuring fetal status) or frequencies of pH below 7.0 (P = 0.73 and 0.34 for failure of descent and nonreassuring fetal status) among the three delivery methods. Birth outcomes and umbilical cord blood gas values were similar for those neonates with a forceps-assisted, vacuum-assisted, or cesarean delivery in the second stage of labor. The occurrence of significant fetal acidemia was not different among the three delivery methods regardless of the indication.

Second trimester cervical length and risk of preterm birth in women with twin gestations treated with 17-α hydroxyprogesterone caproate

OBJECTIVE

To compare rates of preterm birth before 35 weeks based on cervical length measurement at 16-20 weeks in women with twin gestations who received 17-α hydroxyprogesterone caproate (17OHPC) or placebo.

METHODS

This is a secondary analysis of a randomised, double-blind, placebo-controlled trial of twin gestations exposed to 17OHPC or placebo. Baseline transvaginal ultrasound evaluation of cervical length was performed prior to treatment assignment at 16-20 weeks. Cervical length measurements were categorised according to the 10th, 25th, 50th and 75th percentiles in the women studied. The effect of 17OHPC administration in women with a short (25th percentile) and long (75th percentile) cervix was evaluated.

RESULTS

Of 661 twin gestations studied, 221 (33.4%) women enrolled at 11 centers underwent cervical length measurement. The 10th, 25th, 50th, 75th percentiles for cervical length at 16-20 weeks were 32, 36, 40 and 44 mm, respectively. The risk of preterm birth <35 weeks was increased in women with a cervical length <25th percentile (55.8 vs. 36.9%, p=0.02). However, a cervical length >75th percentile at this gestational age interval was not protective for preterm birth (36.5 vs. 42.9%, p=0.42). Administration of 17OHPC did not reduce preterm birth before 35 weeks among those with either a short or a long cervix (64.3 vs. 45.8%, p=0.18 and 38.1 vs. 35.5%, p=0.85, respectively).

CONCLUSION

Women with twin gestations and a cervical length below the 25th percentile at 16-20 weeks had higher rates of preterm birth. In this subgroup of women, 17 OHPC did not prevent preterm birth before 35 weeks gestation. A cervical length above the 75th percentile at 16-20 weeks did not significantly reduce the risk of preterm birth in this high risk population.

Vitamins C and E to prevent complications of pregnancy-associated hypertension

BACKGROUND

Oxidative stress has been proposed as a mechanism linking the poor placental perfusion characteristic of preeclampsia with the clinical manifestations of the disorder. We assessed the effects of antioxidant supplementation with vitamins C and E, initiated early in pregnancy, on the risk of serious adverse maternal, fetal, and neonatal outcomes related to pregnancy-associated hypertension.

METHODS

We conducted a multicenter, randomized, double-blind trial involving nulliparous women who were at low risk for preeclampsia. Women were randomly assigned to begin daily supplementation with 1000 mg of vitamin C and 400 IU of vitamin E or matching placebo between the 9th and 16th weeks of pregnancy. The primary outcome was severe pregnancy-associated hypertension alone or severe or mild hypertension with elevated liver-enzyme levels, thrombocytopenia, elevated serum creatinine levels, eclamptic seizure, medically indicated preterm birth, fetal-growth restriction, or perinatal death.

RESULTS

A total of 10,154 women underwent randomization. The two groups were similar with respect to baseline characteristics and adherence to the study drug. Outcome data were available for 9969 women. There was no significant difference between the vitamin and placebo groups in the rates of the primary outcome (6.1% and 5.7%, respectively; relative risk in the vitamin group, 1.07; 95% confidence interval [CI], 0.91 to 1.25) or in the rates of preeclampsia (7.2% and 6.7%, respectively; relative risk, 1.07; 95% CI, 0.93 to 1.24). Rates of adverse perinatal outcomes did not differ significantly between the groups.

CONCLUSIONS

Vitamin C and E supplementation initiated in the 9th to 16th week of pregnancy in an unselected cohort of low-risk, nulliparous women did not reduce the rate of adverse maternal or perinatal outcomes related to pregnancy-associated hypertension (ClinicalTrials.gov number, NCT00135707).

A multicenter, randomized trial of treatment for mild gestational diabetes

BACKGROUND

It is uncertain whether treatment of mild gestational diabetes mellitus improves pregnancy outcomes.

METHODS

Women who were in the 24th to 31st week of gestation and who met the criteria for mild gestational diabetes mellitus (i.e., an abnormal result on an oral glucose-tolerance test but a fasting glucose level below 95 mg per deciliter [5.3 mmol per liter]) were randomly assigned to usual prenatal care (control group) or dietary intervention, self-monitoring of blood glucose, and insulin therapy, if necessary (treatment group). The primary outcome was a composite of stillbirth or perinatal death and neonatal complications, including hyperbilirubinemia, hypoglycemia, hyperinsulinemia, and birth trauma.

RESULTS

A total of 958 women were randomly assigned to a study group--485 to the treatment group and 473 to the control group. We observed no significant difference between groups in the frequency of the composite outcome (32.4% and 37.0% in the treatment and control groups, respectively; P=0.14). There were no perinatal deaths. However, there were significant reductions with treatment as compared with usual care in several prespecified secondary outcomes, including mean birth weight (3302 vs. 3408 g), neonatal fat mass (427 vs. 464 g), the frequency of large-for-gestational-age infants (7.1% vs. 14.5%), birth weight greater than 4000 g (5.9% vs. 14.3%), shoulder dystocia (1.5% vs. 4.0%), and cesarean delivery (26.9% vs. 33.8%). Treatment of gestational diabetes mellitus, as compared with usual care, was also associated with reduced rates of preeclampsia and gestational hypertension (combined rates for the two conditions, 8.6% vs. 13.6%; P=0.01).

CONCLUSIONS

Although treatment of mild gestational diabetes mellitus did not significantly reduce the frequency of a composite outcome that included stillbirth or perinatal death and several neonatal complications, it did reduce the risks of fetal overgrowth, shoulder dystocia, cesarean delivery, and hypertensive disorders. (ClinicalTrials.gov number, NCT00069576.)

The effect of 17-alpha hydroxyprogesterone caproate on the risk of gestational diabetes in singleton or twin pregnancies

OBJECTIVE

To compare the rates of gestational diabetes among women who received serial doses of 17-alpha hydroxyprogesterone caproate vs placebo.

STUDY DESIGN

Secondary analysis of 2 double-blind randomized placebo-controlled trials of 17-alpha hydroxyprogesterone caproate given to women at risk for preterm delivery. The incidence of gestational diabetes was compared between women who received 17-alpha hydroxyprogesterone caproate or placebo.

RESULTS

We included 1094 women; 441 had singleton and 653 had twin gestations. Combining the 2 studies, 616 received 17-alpha hydroxyprogesterone caproate and 478 received placebo. Among singleton and twin pregnancies, rates of gestational diabetes were similar in women receiving 17-alpha hydroxyprogesterone caproate vs placebo (5.8% vs 4.7%; P = .64 and 7.4% vs 7.6%; P = .94, respectively). In the multivariable model, progesterone was not associated with gestational diabetes (adjusted odds ratio, 1.04; 95% confidence interval, 0.62-1.73).

CONCLUSION

Weekly administration of 17-alpha hydroxyprogesterone caproate is not associated with higher rates of gestational diabetes in either singleton or twin pregnancies.

Long-term outcomes after repeat doses of antenatal corticosteroids

BACKGROUND

Previous trials have shown that repeat courses of antenatal corticosteroids improve some neonatal outcomes in preterm infants but reduce birth weight and increase the risk of intrauterine growth restriction. We report long-term follow-up results of children enrolled in a randomized trial comparing single and repeat courses of antenatal corticosteroids.

METHODS

Women at 23 through 31 weeks of gestation who remained pregnant 7 days after an initial course of corticosteroids were randomly assigned to weekly courses of betamethasone, consisting of 12 mg given intramuscularly and repeated once at 24 hours, or an identical-appearing placebo. We studied the children who were born after these treatments when they were between 2 and 3 years of corrected age. Prespecified outcomes included scores on the Bayley Scales of Infant Development, anthropometric measurements, and the presence of cerebral palsy.

RESULTS

A total of 556 infants were available for follow-up; 486 children (87.4%) underwent physical examination and 465 (83.6%) underwent Bayley testing at a mean (+/-SD) corrected age of 29.3+/-4.6 months. There were no significant differences in Bayley results or anthropometric measurements. Six children (2.9% of pregnancies) in the repeat-corticosteroid group had cerebral palsy as compared with one child (0.5% of pregnancies) in the placebo group (relative risk, 5.7; 95% confidence interval, 0.7 to 46.7; P=0.12).

CONCLUSIONS

Children who had been exposed to repeat as compared with single courses of antenatal corticosteroids did not differ significantly in physical or neurocognitive measures. Although the difference was not statistically significant, the higher rate of cerebral palsy among children who had been exposed to repeat doses of corticosteroids is of concern and warrants further study. (ClinicalTrials.gov number, NCT00015002 [ClinicalTrials.gov].).

The National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network Beneficial Effects of Antenatal Repeated Steroids study: impact of repeated doses of antenatal corticosteroids on placental growth and histologic findings

OBJECTIVE

In utero exposure to repeated doses of antenatal corticosteroids (ACSs) has been shown to reduce fetal growth. Our goal was to evaluate whether weekly betamethasone (R-ACS) alters placental growth and histologic findings.

STUDY DESIGN

In a multicenter randomized controlled trial of R-ACS vs a single course of ACS followed by weekly placebo (S-ACS), placentas were weighed after removal of the membranes and umbilical cord. A single pathologist who was masked to study group and pregnancy outcomes performed histologic evaluation for placental calcifications, infarction, fibrin deposition, and hemorrhage or thrombus formation, acute and chronic chorioamnionitis, fibromuscular vascular hyperplasia, nucleated red blood cells, and villous crowding, edema, fibrosis, or fibrinoid necrosis. Findings were compared between study groups and according to the number of courses of ACS.

RESULTS

One hundred ninety-four placentas were available for evaluation. Univariable analyses revealed no differences between study groups in any of the 19 evaluated histologic parameters between R-ACS and S-ACS groups overall or in analyses that were restricted to deliveries at < 32 or > or = 32 weeks of gestation. Calcifications were more common (P = .045) in the R-ACS group after controlling for other factors. Multivariable analysis revealed increasing gestational age at delivery, but not increasing ACS courses, to be associated with decreasing chorionic inflammation, villous edema, and fibrosis and with increasing villus crowding, fibrin deposition, and calcifications. Ninety-three placentas were weighed before formalin fixation. After controlling for delivery gestation and infant gender, placental weight was significantly lower in the R-ACS group (P = .017) and was related inversely to the number of ACS courses (P = .037). This finding was confirmed only for deliveries at > or = 32 weeks of gestation (525 vs 441 g for R-ACS and S-ACS group, respectively; P = .036).

CONCLUSION

Repeated antenatal corticosteroid treatments in pregnancy are associated with decreased placental growth in a dose-dependent fashion, but not with evident differences in histologic markers of placental inflammation, ischemia, or infarction. Histologic placental abnormalities should not be attributed to repeated courses of corticosteroids.

Gestational diabetes, pregnancy hypertension, and late vascular disease

The complexity of the several pathogenic pathways that cause hypertension and vascular disease and the prolonged interval that appears to predate clinical morbidity have hindered inquiry into the association between GDM and vascular disorders. As a forme fruste of later type 2 diabetes, GDM-affected gravidas are identified as at risk of diabetes-related atherosclerosis, glomerular disruption, and pathogenic retinal angio-genesis. That GDM is evidence for underlying chronic conditions such as dysregulation of innate immune response that, independent of the diabetic state, produces vascular disease is difficult state, produces vascular disease is difficult to assert with the present published literature. Cross-sectional studies of patients with established gestational hypertension or preeclampsia are ambiguous as to the possible pathogenic effect of insulin resistance. Cohort studies initiated in early and mid-pregnancy show evidence that both gestational hypertension and preeclampsia may be more prevalent in gravidas with greater insulin resistance. The association of gestational glucose intolerance with gestational hypertension appears to be independent of obesity and ambient glycemia but explained in part by insulin resistance. Late pregnancy preeclampsia is associated with elevated mid-pregnancy BMI, blood pressure, fasting glucose and insulin, urate, and C-reactive protein, suggestive of metabolic and immune dysregulation. GDM appears to be associated with overexpressed innate immune response, which, in turn, is associated with vascular dysfunction and vascular disease. Among women with GDM, markers of insulin resistance do not appear to correlate with hypertension in short-term cohort studies. However, when non-GDM subjects are compared with subjects with GDM, postpregnancy studies do show an associated with vascular dysfunction and vascular disease. Among women with GDM, markers of insulin resistance do not appear to correlate with hypertension in short-term cohort studies. However, when non-GDM subjects are compared with subjects with GDM, postpregnancy studies do show an association of insulin resistance with both inflammatory dysregulation and vascular dysfunction. Cohort studies that have used population-based pregnancy databases consistently identify a clinically significant association of both gestational hypertension and preeclampsia with later hypertensive disorders. Associations with coronary artery disease or stroke are less consistent, requiring further investigation. Preventing the evolution of diabetes and lipid and immune dysregulation of the metabolic syndrome has become a silent public health issue because of the epidemic of childhood and early adulthood obesity and the opportunity at hand to treat insulin resistance by behavioral and pharmacological interventions. However, limited available literature highlights the need for long-term cohort studies of women with well-characterized metabolic and vascular profiles during pregnancy and decades later. Our present knowledge suggests that screening for GDM provides an opportunity of pregnancy outcome improvement. Limited studies of diabetes prevention in at-risk patient groups suggest that we may have the opportunity to reduce the risk of later diabetes. Additional investigation is required to determine if interventions that prevent or postpone diabetes also delay the onset of vascular disease.

Inflammatory Mediators in Gestational Diabetes Mellitus

The connection between inflammation and insulin resistance has garnered much interest in the past decade. Epidemiologic as well as experimental data have supported the association. The purpose of this article is to review the current evidence linking inflammatory mediators and gestational diabetes mellitus.

Imatinib mesylate and metabolite concentrations in maternal blood, umbilical cord blood, placenta and breast milk

Treatment of maternal chronic myeloid leukemia with imatinib mesylate is avoided because of potential fetal effects. Two women with progression of disease during pregnancy required imatinib therapy. Concentrations of imatinib in maternal blood, placenta, umbilical cord blood and breast milk were 886, 2452, 0 to 157, and 596 ng/ml, respectively. Concentrations of the active metabolite CGP74588 in maternal blood, placenta, umbilical cord blood and breast milk were 338, 1462, 0 and 1513 ng/ml, respectively. As Imatinib and CGP74588 cross the mature placenta poorly, use of the drug after the first trimester may be reasonable under some circumstances. Imatinib and CGP74588 are found in breast milk, and therefore avoidance of breastfeeding is advisable.

Rates of Postpartum Glucose Testing After Gestational Diabetes Mellitus

OBJECTIVE

To estimate rates of postpartum glucose tolerance testing in women diagnosed with gestational diabetes mellitus (GDM) and to assess factors associated with testing.

METHODS

This was a retrospective cohort study of 344 women with GDM who received prenatal care in a maternal diabetes clinic during 2001-2004. Rates of postpartum glucose testing were estimated from hospital, clinic, and laboratory records. Demographic, clinical (obstetric history, antenatal, and delivery), and health care information was obtained from chart review.

RESULTS

Less than one half (45%) of women with GDM in our cohort underwent postpartum glucose testing-more than one third (36%) of whom had persistent abnormal glucose tolerance. After adjusting for clinical and health care characteristics, there was no independent relationship between most demographic characteristics and postpartum testing. Nor was there an association between clinical characteristics and the likelihood of being tested. Postpartum testing was strongly associated only with attendance of the postpartum visit: 54% of women who attended the visit were tested compared with 17% of women who did not attend (adjusted relative risk 3.04, 95% confidence interval 1.75-5.34, P<.001).

CONCLUSION

Although persistent abnormal glucose tolerance was common in our cohort, less than half of the women were tested for it. Our data suggest that to increase rates of postpartum glucose testing, improved attendance at the postpartum visit with greater attention to testing and better continuity between antenatal and postpartum care are required.

LEVEL OF EVIDENCE

II-2.

Single versus weekly courses of antenatal corticosteroids: evaluation of safety and efficacy

OBJECTIVE

The purpose of this study was to determine if weekly corticosteroids improve neonatal outcome without undue harm.

STUDY DESIGN

Women 23 to 32 weeks receiving 1 course of corticosteroids 7 to 10 days prior were randomized to weekly betamethasone or placebo.

RESULTS

The study was terminated by the independent data and safety monitoring committee with 495 of the anticipated 2400 patients enrolled. There was no significant reduction in the composite primary morbidity outcome (8.0% vs 9.1%, P = .67). Repeated courses significantly reduced neonatal surfactant administration (P = .02), mechanical ventilation (P = .004), CPAP (P = .05), pneumothoraces (P = .03). There was no significant difference in mean birth weight or head circumference. The repeat group had a reduction in multiples of the birth weight median by gestational age (0.88 vs 0.91) (P = .01) and more neonates weighing less than the 10th percentile (23.7 vs 15.3%, P = .02). Significant weight reductions occurred for the group receiving > or = 4 courses.

CONCLUSION

Repeat antenatal corticosteroids significantly reduce specific neonatal morbidities but do not improve composite neonatal outcome. This is accompanied by reduction in birth weight and increase in small for gestational age infants.

Acquired von Willebrand disease: management of labor and delivery with intravenous dexamethasone, continuous factor concentrate, and immunoglobulin infusion

Acquired von Willebrand disease is a rare bleeding disorder that can lead to complete absence of clotting factor 8 and von Willebrand factor. Recently, the hematologic literature has reported continuous infusion of factor concentrates and intravenous immunoglobulin as an improved therapy for active bleeding and prophylaxis in patients who are anticipating surgery with congenital von Willebrand disease. We describe the first case of a pregnant woman with acquired von Willebrand disease who underwent the described therapy during delivery.

Preterm premature rupture of membranes: risks of recurrent complications in the next pregnancy among a population-based sample of gravid women

OBJECTIVE

The purpose of this study was to ascertain the predictive value of antecedent preterm premature rupture of membranes for recurrent preterm premature rupture of membranes and preterm delivery rates in the next pregnancy compared with background rates among a population-based sample of women at a single institution.

STUDY DESIGN

Records of patients with index singleton pregnancies that were complicated by preterm premature rupture of membranes whose next delivery resulted in a delivery at >or=20 weeks at the same institution were reviewed for the incidence and gestational age of recurrent preterm premature rupture of membranes and preterm delivery. All subjects were patients of physicians whose obstetric practices were based at a single institution. Background rates of preterm premature rupture of membranes and preterm delivery in this population were generated from a systematically selected comparison group composed of the two deliveries after each of the study group's second delivery.

RESULTS

The rates of recurrent preterm premature rupture of membranes (16.7%) and preterm delivery (34.2%) in the 114 study group patients were substantially greater (odds ratio, 20.6; 95% CI, 4.7-90.2; and odds ratio, 3.6; 95% CI, 2.1-6.4) than noted background rates (0.96% and 12.5%) but considerably less than the recurrence rates of either preterm premature rupture of membranes or preterm delivery that were reported by others. The gestational age of preterm premature rupture of membranes in the index pregnancy affected neither the magnitude of risk nor the gestational age of recurrent preterm premature rupture of membranes or preterm delivery in the subsequent pregnancy. Stratification of outcome measures into three subgroups that were based on the gestational age of index preterm premature rupture of membranes demonstrated no significant differences in the incidence of preterm premature rupture of membranes or preterm delivery.

CONCLUSION

After a pregnancy that was complicated by preterm premature rupture of membranes, the risk for recurrent preterm premature rupture of membranes is increased by 20-fold and for recurrent preterm delivery by almost 4-fold. Gestational age of antecedent preterm premature rupture of membranes is predictive of neither risk nor timing of recurrent complications. Estimates of recurrence risks appear to be moderated by limiting analysis to a population-based sample of gravid women when compared with previous studies.

Amniotic fluid insulin at 14-20 weeks' gestation: association with later maternal glucose intolerance and birth macrosomia

OBJECTIVE

To examine the hypothesis that early second trimester amniotic fluid (AF) insulin concentration is elevated and later fetal growth is augmented in gravidas demonstrating later oral glucose intolerance.

RESEARCH DESIGN AND METHODS

In this prospective observational cohort study, AF was sampled at 14-20 weeks' gestation in 247 subjects, and 1-h 50-g oral glucose challenge tests (GCTs) were performed at > or = 24 weeks. AF insulin was assayed by an automated immuno-chemiluminometric assay (8). Macrosomia was defined as birth weight above the 90th centile.

RESULTS

AF insulin concentration (range 1.4-44.5 pmol/l) correlated positively with gestational age and maternal weight. A logistic regression analysis, adjusted for maternal age and midpregnancy weight, showed increased AF insulin multiples of gestational age-specific medians to be associated with subsequently diagnosed gestational diabetes mellitus (GDM) (OR 1.9, CI 1.3-2.4, P = 0.029). Among 60 subjects with GCT values > 7.2 mmol/l, each unit increase in AF insulin multiple of median (MOM) was associated with a threefold increase in fetal macrosomia incidence (3.1, 1.3-4.9, P = 0.048).

CONCLUSIONS

An elevated AF insulin concentration at 14-20 weeks' gestation is associated with subsequently documented maternal glucose intolerance. Among gravidas with GCT values > 7.2 mmol/l, elevated early AF insulin concentration is associated with fetal macrosomia. Maternal glucose intolerance may affect fetal insulin production before 20 weeks' gestation.

Midpregnancy serum C-peptide concentration and subsequent pregnancy-induced hypertension

OBJECTIVE

To test the hypothesis that elevated midpregnancy serum insulin (IRI) and C-peptide (CP) concentrations are associated with later development of pregnancy-induced hypertension (PIH), independent of prepregnancy obesity and midpregnancy blood pressure.

RESEARCH DESIGN AND METHODS

In this prospective study, a cohort of normotensive women, ages > or = years performed a 50-g glucose challenge test at 24-30 weeks' gestational age. Blood samples were collected after an overnight fast and 1 h after glucose ingestion. Serum IRI and CP concentrations were measured in each sample. Maternal height, blood pressure and proteinuria were measured at the time of glucose challenge testing and after 36 weeks' gestational age.

RESULTS

Of 320 subjects enrolled 44 women (13.8%) had subsequent PIH. Crude odds ratios (ORs) for devevelopment of PIH associated with each 1 U rise in log fasting IRI, log lasting CP. and glucosed-induced increase in CP (expressed as log [postprandial CP/fasting CP]) were 2.0 (95% CI 1.3-3.3), 1.8 (CI 1.2-2.7), and 2.3 (CI 1.1-4.9) respectively. After controlling for prepregnancy BMI, gestational age, and midpregnancy mean arterial pressure, adjusted ORs corresponding to log fastig IRI and CP for the development of PIH were 1.3 (95% CI 0.7-2.3) and 1.7 (CI 1.1-2.7) respectively, and, afterq adjustment for fasting CP, the adjusted OR of the glucose-induced rise in log CP was 3.7 (CI 1.5-9.3).

CONCLUSIONS

Mid-pregnancy tasting and postoral glucose CP levels are associated with subsequent development of PIH, independent of maternal obesity and midpregnancy baseline blood pressure. These findings many reflect an amplified beta3-cell response to glycemic stimulus, similar to that found in states of insulin resistance, that appears to be independently associated with PIH.

Glucocorticoid-associated maternal hyperglycemia: a randomized trial of insulin prophylaxis

OBJECTIVES

To study the degree and timing of maternal hyperglycemia following betamethasone therapy in nondiabetic patients and establish a prophylactic dose of insulin.

METHODS

Forty-five patients receiving betamethasone 12 mg i.m. at 7 AM on two consecutive days were randomized to no insulin (n = 20), low-dose insulin (n = 18), and high-dose insulin (n = 7) protocols. Each treatment group received s.c. insulin at 7 AM on the 2 days of betamethasone therapy (20 units NPH/10 units regular, and 40 units NPH/20 units regular, respectively). Capillary plasma glucose measurements were obtained at fasting and 2 h after meals for 3 days. A multivariate normal regression model was used to estimate and compare mean glucose levels.

RESULTS

Eighty-five percent of patients who did not receive insulin exhibited hyperglycemia at levels previously associated with fetal acidosis. Significant differences in mean postprandial plasma glucose levels were found between the no-treatment and insulin groups on days 1 and 2. No significant differences were noted between groups on day 3.

CONCLUSIONS

Transient maternal hyperglycemia occurs in a consistent pattern in nondiabetic patients receiving betamethasone, which can be limited by the concurrent use of insulin. Further studies to assess fetal acidosis in this setting are warranted.

Outcome of very low birth weight infants with histopathologic chorioamnionitis

OBJECTIVE

To determine neonatal outcome at 7 months of corrected age in very low birth weight (VLBW) infants with placental chorioamnionitis.

METHODS

We conducted a cohort study of 287 VLBW infants delivered as a result of preterm premature rupture of membranes (PROM) or preterm labor. Control subjects (n = 123) had placentas with absent umbilical cord inflammation and absent or low-grade membrane inflammation. Case subjects (n = 164) had moderate membrane inflammation or any umbilical cord inflammation. Neonatal and 7-month outcomes were compared. A power analysis showed that 98 total subjects were needed to reject the two-sided null hypothesis with a difference in mean Bayley index scores of at least 8.

RESULTS

Infants in the study group had significantly more preterm PROM, antenatal antibiotics, lower birth weight, lower gestational age, longer duration of ruptured membranes, and clinical chorioamnionitis. Intraventricular hemorrhage occurred more commonly in infants with placentas demonstrating chorioamnionitis (relative risk = 1.6, 95% confidence interval 1.1, 2.4, P =.013). One hundred sixty-seven (69%) of the 243 surviving infants had 7-month follow-up. There was no difference between cases and controls in mean Bayley mental developmental index (93 compared with 90, P =.25), psychomotor developmental index (89 compared with 90, P =.68), or in the number of infants that were developmentally delayed.

CONCLUSION

Despite a higher frequency of intraventricular hemorrhage, no difference in developmental scores was detected at 7 months of corrected age in VLBW infants with histologic chorioamnionitis.

Lethal fetal renal anomalies and obstetric outcome

The incidence of prenatal and intrapartum complications was examined among 33 pregnancies complicated by lethal fetal renal abnormalities (cases) and compared to 200 contemporaneous control pregnancies (controls) by retrospective record review. Cases experienced higher rates of antepartum bleeding (29% vs. 6%, p<0.0001) stillbirth (15% vs. 0%, p<0.0001), preterm birth (34.3+/-4.1 vs. 39.7+/-1.8, p<0. 0001) and breech presentation (48% vs. 4%, p<0.0001). Twenty-six of 33 cases had lung weights </= first centile. Primary cesarean section occurred more frequently in cases than in controls (48% vs. 9%, p<0.0001). Knowledge of poor fetal prognosis alone did not appear to influence obstetrical management. We conclude that timely consultation with sonologist and neonatologist and patient counseling may avoid unnecessary obstetrical intervention when pregnancy complications occur. Pregnancies complicated by lethal fetal renal abnormalities have higher rates of ante- and intrapartum complications leading to frequent abdominal delivery. This suggests that accurate predictive markers for lethal fetal renal disease may reduce ineffective obstetric intervention.

A high-sensitivity assay for amniotic fluid insulin at 14-20 weeks' gestation

OBJECTIVE

To examine sensitivity, precision, and sample stability of an immunochemiluminomimetric insulin assay in 14-20 week amniotic fluid (AF) and fetal age distribution of second-trimester AF insulin concentrations.

METHODS

We assayed fresh specimens from 576 gravidas who had amniocentesis at 14-20 weeks' gestation because of maternal age. In a preliminary study, samples were divided into aliquots and stored at 4C and -20C for 24 hours to assess freezing effect. Some samples stored at 4C were assayed repeatedly during a 14-day period and others, stored at -20C, were assayed after a 70-day period.

RESULTS

This assay reliably measured AF insulin to a detection limit of 0.03 microIU/mL. Insulin could be measured in all amniotic fluid samples and demonstrated a log10 Gaussian distribution, ranging from 0.24 to 7.41 microIU/mL. Interassay coefficients of variation ranged from 4.4 to 8.9% at concentrations of 0.4-2.0 microIU/mL. Linearity of dilution from 1.5 to 10 times was 99.2 +/- 8.6%. Spike recovery of 10 microIU/mL was from 92-109%. Recovery after freezing to -20C for 24 hours (101%) and 70 days (97%) and after storage at 4C for 14 days (97%) demonstrated no significant loss.

CONCLUSION

A two-site, dual monoclonal, immunochemiluminomimetric insulin assay was sufficiently sensitive and precise within the lower range of measured AF insulin concentrations to investigate clinical associations of 14-20 week AF insulin with maternal and fetal conditions. The insulin stability in this matrix suggests that assays can be reliable on specimens stored up to 70 days.

Influence of chorioamnionitis on developmental outcome in very low birth weight infants

OBJECTIVE

To determine the effect of exposure to chorioamnionitis on developmental outcome in very low birth weight (VLBW) infants.

METHODS

Five hundred four maternal charts (97% of all VLBW infants delivered from 1990 to 1994) were reviewed. A historical cohort study of the 330 infants delivered secondary to preterm premature rupture of membranes or preterm labor was performed. Case subjects (71) were delivered of mothers with chorioamnionitis by clinical criteria; control subjects (259) were delivered of mothers without chorioamnionitis. Bayley index scores at 7 months' corrected age and special care nursery outcomes were compared. One hundred seventy-three subjects were necessary to reject the two-sided null hypothesis with 80% power with a difference in mean Bayley index scores of at least 8.

RESULTS

Neonatal sepsis (8.5% compared with 1.9%; odds ratio [OR] = 4.7, 95% confidence interval [CI] 1.4, 15.9, P = .015) and a low 5-minute Apgar (72% compared with 55%; OR = 2.1, CI 1.2, 3.8, P = .012) occurred more frequently in the chorioamnionitis group. One hundred eighty-seven (68%) of 273 surviving neonates had follow-up. Cases and controls were similar in mean Bayley mental developmental index (91.2 compared with 91.8, P = .84), Bayley psychomotor developmental index (89.8 compared with 89.1, P = .82), and number of infants developmentally delayed. Duration of exposure to chorioamnionitis did not affect neonatal outcome.

CONCLUSION

Despite higher rates of sepsis and low Apgar scores, no difference in outcome at 7 months of corrected age was detected in VLBW infants exposed to chorioamnionitis. Contemporary neonatal management may reduce the adverse effects of this exposure.

The effect of pregnancy on the natural history of diabetic retinopathy and nephropathy

Retinopathy and nephropathy are complications of diabetes mellitus that can affect women of reproductive age. This article focuses on the effect of pregnancy on the risk of progression of microvascular disease, both during gestation and at long-term follow-up. Fortunately, with intensive medical surveillance and appropriate interventions, most women with types 1 and 2 diabetes mellitus can be offered an optimistic prognosis for child bearing.

The diagnosis of gestational diabetes

The concept of gestational diabetes goes back at least to 1946. Over the years, sophistication has increased regarding the pathophysiology of this condition. However, there is not universal agreement on how to diagnose gestational diabetes. The most widely used diagnostic criteria in the U.S. were validated by their predictive value for subsequent diabetes in the mother, rather than by their ability to identify risk to the fetus and newborn. The best available evidence supports the notion that the relationship between carbohydrate intolerance in pregnancy and adverse perinatal outcomes is a continuous one, and no single cutoff can separate pregnant women into those with high risk and those with no risk at all. Suggestions are made for arriving at appropriate, albeit arbitrary, diagnostic criteria.

The relationship between second-trimester amniotic fluid insulin and glucose levels and subsequent gestational diabetes

Associations between elevated amniotic fluid glucose and insulin levels in the second trimester and the subsequent development of gestational diabetes have been reported. We conducted a case-control study to determine which analyte best predicts future maternal glucose intolerance. Thirty-nine women diagnosed with gestational diabetes (criteria of Carpenter and Coustan, Am. J. Obstet. Gynecol., 144, 768, 1982) who had undergone genetic amniocentesis for advanced maternal age were matched with euglycaemic controls. Glucose and insulin concentrations were determined by analysis of stored amniotic fluid samples. No significant difference was detected between cases and controls for amniotic fluid glucose concentrations. Amniotic fluid insulin concentrations were significantly higher in cases (mean rank 4.44, P < 0.01, using matched rank analysis of variance, where 1 is the lowest and 6 is the highest rank). After conversion to multiples of the median, 20 per cent of women with subsequent gestational diabetes were found to have amniotic fluid glucose levels at or above the 90th centile, while 35 per cent of cases had similarly elevated amniotic fluid insulin levels. We conclude that second-trimester amniotic fluid insulin is a more sensitive predictor of impending glucose intolerance than amniotic fluid glucose, although neither is sufficiently powerful to use alone as a screening test.

Positional effects on maternal cardiac output during labor with epidural analgesia

OBJECTIVE

Our purpose was to test the hypothesis that the supine versus the lateral position is associated with a greater decrement in cardiac output after epidural analgesia in labor.

STUDY DESIGN

Twenty-one normal term subjects were randomized to the left lateral or supine position in early labor. Cardiac output measured by the acetylene rebreathing method, stroke volume, heart rate, mean arterial pressure, and systemic vascular resistance were obtained at 5-minute intervals, beginning before a 500 ml intravenous fluid bolus (baseline) and ending 45 minutes after epidural injection.

RESULTS

Mean baseline supine versus lateral group differences were significant for 21% lower cardiac output, 21% lower stroke volume, 19% higher mean arterial pressure, 50% higher systemic vascular resistance, and equivalent heart rate. In the supine group fluid bolus resulted in significantly increased cardiac output and stroke volume, decreased mean arterial pressure and systemic vascular resistance, and unchanged heart rate. In the supine group cardiac output and stroke volume decreased significantly after epidural injection. The lateral position group exhibited no hemodynamic alterations after fluid bolus or epidural.

CONCLUSIONS

In contrast to the lateral position, the supine position is associated with a significant postepidural decrement in cardiac output, not identified by a change in heart rate. This likely reflects an inability to maintain stable preload volume in the supine position.

Exercise fails to improve postprandial glycemic excursion in women with gestational diabetes

The effect of an acute period of moderate intensity exercise on maternal glycemic excursion following a mixed nutrient meal was studied. Five normal (NL) and six gestational diabetic (GDM) subjects were enrolled. A randomized crossover design was used to compare fasting glucose and insulin levels, peak glucose and insulin levels and incremental area of the glycemic and insulin curves following a mixed nutrient meal with or without an exercise stress that took place 14 h earlier. Exercise consisted of upright stationary cycling for 30 min at a heart rate consistent with 60% VO2max. The clinical characteristics of normal and gestational diabetic subjects were comparable. Mean values (+/-SEM) with, versus without, exercise for fasting glucose (NL: 78.9 +/- 2.6 vs. 80.0 +/- 2.6 mg/dl; GDM: 86.4 +/- 2.0 vs. 82.1 +/- 3.5 mg/ dl), peak glucose (NL: 132.3 +/- 10.4 vs. 139.1 +/- 15.6 mg/dl; GDM: 165.8 +/- 5.5 vs. 160.3 +/- 7.8 mg/dl), the area under the glycemic curve (NL: 5758 +/- 1038 vs. 6393 +/- 1281 mg/dl.min; GDM: 8,178 +/- 890 vs. 8,331 +/- 563 mg/dl.min) did not differ. Similarly, plasma insulin levels did not differ between protocols for either group of subjects. Exercise has been proposed as a treatment to reduce glycemia in gestational diabetes. Results from this study indicate a single bout of exercise did not blunt the glycemic response observed following a mixed nutrient meal.