Factors and outcomes associated with longer latency in preterm premature rupture of membranes

Objective. To examine factors and outcomes associated with latency in preterm premature rupture of membranes (PPROM). Methods. A retrospective cohort study was conducted of all deliveries with a diagnosis of PPROM at 24-34 weeks of gestation at an academic medical center for the period 1980-2001. Gestational age at PPROM was examined as the primary independent variable. Primary outcome was duration from rupture of membranes until delivery. The association with neonatal and maternal perinatal morbidity was examined with duration of latency. Dichotomous outcomes were compared using the Chi-square test. Multivariable regression analyses were performed to control for potential confounding variables. Results. One thousand one hundred and sixty-eight patients were identified. Latency duration was inversely associated with gestational age at time of PPROM (p<0.001). These findings persisted when potential confounders were controlled for in multivariable models. Neonatal sepsis and chorioamnionitis were not associated with increased duration of latency. Conclusion. Earlier gestational age at time of PPROM is associated with longer latency duration, which, in turn, is not associated with increased neonatal sepsis or chorioamnionitis. These data can be used to counsel patients with PPROM about expected duration of latency and outcomes.