Risk of Early-Onset Sepsis following Preterm, Prolonged Rupture of Membranes with or without Chorioamnionitis

Objective This study aims to determine whether preterm prolonged rupture of membranes (PPROM) increases the risk for early-onset sepsis (EOS) in preterm infants. Study Design Retrospective cohort study of infants 30 to 34 weeks' gestation from 2005 to 2014. Exposure to PPROM (rupture of membranes >= 18 hours) or chorioamnionitis (maternal temperature >= 38 degrees C during delivery plus notation of chorioamnionitis in the medical record) was collected. The primary outcome was proven or suspected EOS. Results A total of 2,192 infants were included. Overall, 1,750 (80%) were not exposed to PPROM or chorioamnionitis (group 1), 381 (17%) were exposed to PPROM without chorioamnionitis (group 2), and 61 (3%) were exposed to chorioamnionitis +/- PPROM (group 3). There was no difference in the incidence of proven or suspected EOS between groups 1 and 2 (5.4 vs. 5.5%, p = 0.86). Group 3 had a higher rate of EOS (24.6%) relative to groups 1 and 2 (p < 0.001). In multivariate analysis, risk of EOS was 4.1 times higher in infants exposed to chorioamnionitis. PPROM did not increase the risk of EOS in bivariate or multivariate analysis. Conclusion In the absence of chorioamnionitis, PPROM does not increase the risk of proven or clinically suspected EOS in 30 to 34 weeks' gestation infants.