Predictors for cesarean delivery in preterm premature rupture of membranes.

Objective: To determine predictors for cesarean delivery (CD) in pregnancies complicated by preterm premature rupture of membranes (PPROM) with an intention for vaginal delivery.Materials and methods: A retrospective cohort analysis of all singleton, preterm deliveries (24 + 0 to 36 + 6 weeks) following PPROM (2007-2014). Exclusion criteria included: cases intended for CD prior to delivery; short interval from PPROM to delivery (<24 hours); cervical dilatation upon admission ≥4 cm; and major fetal anatomical/chromosomal abnormalities. Potential CD predictors were evaluated by univariate followed by multivariate regression analysis.Results: Overall, 465 deliveries met inclusion criteria. Of them, 53 (11.4%) ended with CD. Women in the CD group delivered at an earlier gestational age (34 versus 35 weeks) with lower birth weights (2115 versus 2386 grams), p < .05 for both. On univariate analysis, smaller cervical dilatation upon admission and prior to delivery, longer PPROM to delivery interval and delivery indication were the only significant determinants associated CD (p < .001 for all). On multivariable regression analysis, only la rger cervical dilatation prior to delivery remained an independent factor for lower rates of CD (aOR 0.15, 95% CI 0.08-0.28, p < .001).Conclusion: Small cervical dilatation prior to delivery is an independent risk factor for CD in pregnancies complicated by PPROM.