Objective: To investigate the association of epidemiological and pregnancy-related parameters with the latency period achieved in cases of preterm premature rupture of membranes (PPROM).
Method: A retrospective study was performed enrolling cases admitted in high-risk pregnancy unit (HRPU) with PPROM between 24 + 0 and 36 + 6 gestational week during 2002-2011. Cases with vaginal bleeding at admission, co-existing maternal or fetal pathology, placenta praevia, previous interventions in cervix or uterus, triplets or higher order pregnancies were excluded. Epidemiological parameters and latency period between admission due to PPROM and delivery were recorded. Obstetrical complications, mode of delivery, and neonatal morbidity parameters were also studied. A multivariate regression model was used to correlate latency period with epidemiological and pregnancy-related risk factors.
Results: Overall, there were 319 cases of PPROM admitted, of which 303 (94.9%) met inclusion criteria. Median latency period was 5.2 d. The latency interval exceeded 48 h in 65.0% of cases (197/303). Emergency cesarean was demanded in 20.2% of cases, chorioamnionitis was diagnosed in 7.5% while 76.1% of neonates were admitted in neonatal intensive care unit. Higher gestational week at admission was associated with shorter latency interval (p < 0.001), twin pregnancy with shorter latency interval (p = 0.02), while latency interval was significantly lower in cases complicated with chorioamnionitis (p = 0.048).
Conclusion: Gestational week at PPROM, twin gestation and chorioamnionitis are factors significantly affecting latency interval.