Neonatal morbidity at 34-37 weeks: The role of ruptured membranes

Objective: Evaluate neonatal morbidity in deliveries occurring between 34 0 /7 and 36 6/7 weeks' gestation, comparing outcomes in pregnancies complicat ed by preterm premature rupture of membranes with those in which delivery o ccurred with intact membranes prior to the onset of labor. Methods: The obstetric database was reviewed for a 5-year period. Healthy g ravidas delivering nonanomalous singleton gestations from vertex presentati ons were evaluated, with corticosteroid or antibiotic administration or bot h noted. The neonatal database was reviewed for the following complications : admission to the neonatal intensive care unit, need for assisted ventilat ion, and development of hyaline membrane disease, bronchopulmonary dysplasi a, intraventricular hemorrhage, necrotizing enterocolitis, or culture-prove n sepsis. Groups were compared using chi(2) tests. The power of this study to detect a ten-fold decrease in the likelihood of neonatal complications a t the P < .05 significance level was greater than 90%. Results: Of 853 eligible pregnancies, 414 (48.5%) gravidas had ruptured mem branes prior to the onset of active labor. No difference existed between gr oups in the number of patients who had received corticosteroids during preg nancy, but patients with ruptured membranes were more likely to have receiv ed antibiotics prior to delivery. No neonatal deaths occurred, and neonatal morbidity was low in both groups. Conclusion: No clinically significant difference exists in neonatal outcome between 34 Oh and 36 6/7 weeks' gestation as the result of membrane status prior to the onset of labor. (C) 1999 by The American College of Obstetric ians and Gynecologists.