Preterm premature rupture of membranes: does the duration of latency influence perinatal outcomes?

Objective Preterm premature rupture of membranes (PPROM) is the leading identifiable cause of prematurity. We hypothesized that, when controlled for delivery gestational age, potential prolonged exposure to inflammation/infection could be harmful to the developing fetus. Study Design We studied a retrospective cohort of pregnancies with PPROM at 22.0–33.9 weeks' gestation. The primary outcome was perinatal survival without major morbidity (grade III/IV intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia). Regression models assessed predictors of perinatal morbidity. Results Three hundred six women were included. PPROM occurred at a median of 29.4 weeks' gestation (interquartile range [IQR], 24.7–32.1 weeks' gestation). Median latency was 8 days (IQR, 3–15 days). Median delivery age was 31.4 weeks' gestation (IQR, 27.4–33.3 weeks' gestation). Two hundred seventy-seven infants (91%) survived; 233 infants (84% of survivors, 76% of all babies) did not have major morbidities. Gestational age (odds ratio, 0.60; 95% confidence interval, 0.53–0.68) and congenital sepsis (odds ratio, 13.2; 95% confidence interval, 3.9–44.5), but not latency, predicted perinatal morbidity in multivariate models. Conclusion Latency does not appear to worsen outcomes in pregnancies that are complicated by PPROM.