Timing of induction for term prelabor rupture of membranes and intravenous antibiotics

Background: Induction of labor usually within 24 hours is recommended for term prelabor rupture of membranes. It is still unclear when within the 24 hours induction of labor for term prelabor rupture of membranes should be initiated. Antibiotic prophylaxis for group B Streptococcus is usually recommended for prolonged prelabor rupture of membranes. Objective: The aim of our study was to evaluate whether induction of labor at ≤6 hours from prelabor rupture of membranes with intravenous oxytocin in singleton pregnancies at ≥37 weeks’ gestation without regular uterine contractions reduces the administration of intravenous antibiotic agents. Study Design: This was a retrospective cohort study including all women with prelabor rupture of membranes at ≥37 weeks’ gestation and without regular uterine contractions in which labor was induced using intravenous oxytocin. Women were divided into 2 groups according to the timing of induction (≤6 hours vs >6 hours after prelabor rupture of membranes). Results: A total of 166 women with term prelabor rupture of membranes were included, 53 of whom (31.9%) were induced within 6 hours of prelabor rupture of membranes and 113 (68.1%) were induced after 6 hours. There were no differences in demographic characteristics and risk factors for term prelabor rupture of membranes between the 2 groups. Women who underwent induction of labor at ≤6 hours were significantly less exposed to intravenous antibiotic prophylaxis compared with women induced at >6 hours (36% vs 80.5%, respectively; odds ratio, 0.14; 95% confidence interval, 0.07–0.28). Furthermore, for women induced within 6 hours after prelabor rupture of membranes, the chances of delivering at <12 or <24 hours were increased, nonreassuring cardiotocogram significantly less common, and hospital stay significantly shorter. No differences were found in regard to neonatal outcomes. Conclusion: Induction of labor at ≤6 hours with intravenous oxytocin after term prelabor rupture of membranes is significantly associated with lesser use of antibiotic agents, shorter latency to delivery, lower incidence of nonreassuring cardiotocogram, and shorter hospital stay than induction of labor at >6 hours after prelabor rupture of membranes.