Infectious morbidity and microbiological findings in early and late preterm prelabor rupture of membranes managed expectantly

OBJECTIVE: The objective of this study was to describe and compare maternal infectious morbidity, microbiological findings, and neonatal outcomes among pregnancies with early (<34 weeks) and late (34 + 0-36 + 6 weeks) prelabor rupture of membranes (PPROM) managed expectantly at a single tertiary referral center. METHODS: This single-center retrospective cohort study included consecutive singleton pregnancies complicated by PPROM at ≥24 weeks of gestation and managed expectantly at Galilee Medical Center, a university-affiliated tertiary referral center in Nahariya, Israel, between August 2017 and May 2024. Patients were categorized according to gestational age at membrane rupture into early (n = 136) and late (n = 548) PPROM. Expectant management was applied using a 7-day antibiotic regimen (ampicillin-based until March 2023, followed by cefuroxime-based prophylaxis). Patients with active labor or clinical infection at admission were excluded. Primary outcomes were clinical chorioamnionitis and early-onset neonatal sepsis. RESULTS: Late PPROM was associated with lower rates of postpartum maternal infectious morbidity than early PPROM, including lower rates of intrapartum fever (2.6% vs. 6.6%), postpartum fever (0.2% vs. 2.9%), and surgical site infection (0.8% vs. 12.3%). In exploratory adjusted analysis, cefuroxime-based prophylaxis was associated with lower observed odds of clinical chorioamnionitis compared with ampicillin-based prophylaxis, whereas late versus early PPROM was not independently associated with clinical chorioamnionitis. CONCLUSION: Among pregnancies with PPROM managed expectantly, late PPROM was associated with lower observed rates of maternal infectious morbidity compared with early PPROM.