Vascular placental pathology and the relationship between hypertensive disorders of pregnancy and neonatal outcomes in very low birth weight infants.

OBJECTIVE: To investigate vascular placental pathology's effect on known associations between hypertensive disorders and four adverse neonatal outcomes-bronchopulmonary dysplasia, intraventricular hemorrhage or periventricular leukomalacia, necrotizing enterocolitis, and death.

STUDY DESIGN: Retrospective cohort of very low birth weight neonates born at a single center (n = 911). Statistical analysis included χ2 , t test, modified Poisson regression with robust error variance to measure risk, and Wald test. Stratified models assessed the effect of maternal hypertension on neonatal outcomes in those exposed to placental pathology.

RESULTS: Neonates exposed to maternal hypertension and placental pathology had an increased risk of bronchopulmonary dysplasia (relative risk (RR) = 5.23, 95% confidence interval (CI): 2.07, 13.22) compared to those exposed to hypertension without placental pathology (RR = 1.63, 95% CI: 1.14, 2.34; Wald test p = 0.02). Similar, but non-significant, trends also emerged for necrotizing enterocolitis and death.

CONCLUSION: Vascular placental pathology may amplify the risk of adverse outcomes in neonates exposed to hypertension and may mark the extent to which hypertension affects neonates.