479: Late preterm neonatal morbidity in high-risk hypertensive versus normotensive women

479 Late preterm neonatal morbidity in high-risk hypertensive versus normotensive women Cynthia Gyamfi-Bannerman, Victoria Fratto, Cande Ananth Columbia University Medical Center, Dept of Obstetrics and Gynecology, New York, NY OBJECTIVE: Late preterm (LP, 34 0/7 to 36 6/7 weeks) neonatal morbidity is now well-described. We previously reported the associations of neonatal respiratory morbidity in relation to mild and severe elevations in blood pressure (BP) in low-risk women. We now hypothesized that elevated BP will be associated with increased risk of late preterm neonatal morbidity in women with history of chronic hypertension, preeclampsia (PEC), or insulin-dependent diabetes in the current pregnancy (the “high-risk” cohort). STUDY DESIGN: This is a secondary analysis of a Maternal-Fetal Medicine Units Network study of aspirin to prevent preeclampsia in highrisk women (defined above). Women that delivered non-anomalous singleton births at 34 weeks were divided into 3 groups: normotensive, mild PEC or gestational hypertension (GH), and severe PEC/GH. The primary outcomes included respiratory (respiratory distress syndrome (RDS) or intubation) and non-respiratory (bronchopulmonary dysplasia, intraventricular hemorrhage, retinopathy of prematurity, SGA 10%, NICU admission, perinatal death, pulmonary hypertension, seizures, and 5 min Apgar 5) morbidity. We also analyzed these associations within sub-groups of women with a history of chronic hypertension, preeclampsia, or insulin-dependent diabetes in the current pregnancy. Analyses were adjusted for a variety of confounding factors. RESULTS: Of the 1542 women that met the inclusion criteria, 18.9% (n 256) and 14.3% (n 184) were diagnosed with mild or severe hypertension respectively. When compared to normotensive women, LP delivery rates were higher in women with mild PEC/GH (31.3% versus 15.8%; P 0.001) and in women with severe PEC/GH (42.4% versus 15.8%; P 0.001). The associations of respiratory morbidity in relation to hypertension groups are shown in the Table. CONCLUSION: In this cohort of high-risk women, the increased risk of late preterm neonatal morbidity in women that develop severe PEC/GH is evident only among infants that have morbidity that are non-respiratory in etiology. 480 The risks of neonatal sepsis and respiratory morbidity in fetuses exposed to corticosteroids after preterm PROM Cynthia Gyamfi-Bannerman, Chia-Ling Nhan-Chang, Cande Ananth Columbia University Medical Center, Dept of Obstetrics and Gynecology, New York, NY OBJECTIVE: Controversy exists regarding administration of antenatal corticosteroids (ACS) among women with preterm premature rupture of membranes (PPROM) after 30-32 weeks gestation. Reasons cited include (i) increased risk of neonatal sepsis; and (ii) increased fetal stress after PPROM causing endogenous steroid production and negating possible benefit. We sought to assess the risk of neonatal sepsis and respiratory distress syndrome (RDS) in a cohort of women with PPROM from 30 0/7 to 36 6/7 weeks of gestation. STUDY DESIGN: This is a secondary analysis of a Maternal-Fetal Medicine Units Network multicenter, observational study regarding mode of delivery after prior uterine surgery. Women with singleton gestations delivering from 30 0/7 to 36 6/7 weeks exposed to ACS were compared to women delivering at the same gestational ages who were unexposed. Associations between steroid exposure and risks of neonatal sepsis and RDS were estimated through a propensity score (PS) analysis based on log-linear regression models. These models were weighted based on the inverse probability of treatment weight. RESULTS: We identified 1743 women with PPROM who met inclusion criteria; of those 48% (n 836) received ACS. The mean gestational age was, on average, 2 weeks lower in women exposed to ACS than those unexposed (32.5 versus 34.7 weeks, P 0.001). In the unadjusted analyses, the risks of both RDS and sepsis were 40% and 60% higher in the ACS-exposed than in the unexposed groups. However, when these risks were adjusted for confounders at baseline (age, nulliparity, race, single marital status) and gestational age at delivery through a PS-based analysis, prenatal exposure to corticosteroid exposure was no longer associated with increased risks of both RDS and sepsis. CONCLUSION: In a cohort of women with PPROM, ACS exposure was not associated with increased risks of respiratory morbidity or neonatal sepsis. The PS method safeguards against treatment (steroid) selection bias in this observational cohort study. Odds of neonatal morbidity by blood pressure group Risk of neonatal morbidity by BP group in high-risk women www.AJOG.org Doppler Assess, Fetus, Prematurity, U/S, Med-Surg-Diseases Poster Session III