Labor induction in term nulliparous women with premature rupture of membranes: oxytocin versus dinoprostone

Abstract

Introduction: Premature rupture of the membranes (PROM) refers to rupture of the fetal membranes prior to the onset of regular uterine contractions. Premature rupture of the membranes continues to be one of the most vexing issues of obstetrics due to increased maternal and fetal morbidity and mortality. Many studies have focused on how management should be in these cases. The purpose of this study was to investigate whether dinoprostone (PGE₂ analogue) administration is necessary for cervical ripening and labor induction in term women with premature rupture of membranes (PROM) and to compare maternal and neonatal outcomes between oxytocin usage and dinoprostone usage in PROM.

Material and methods: A total of 224 nulliparous singleton pregnant women at term, with PROM ≥ 12 h, vertex presentations, no prior uterine surgery, reactive non-stress test and Bishop scores ≤ 6 (unfavorable cervixes) were reviewed. Participants were divided into two groups as oxytocin and dinoprostone groups. The primary outcome was vaginal delivery within 24 h.

Results: The women in the oxytocin group were significantly younger than in the dinoprostone group (22.85 ±4.10 years vs. 25.99 ±4.94 years; p = 0.001). There were significant differences in vaginal delivery rates within 24 h. It was 72 of 112 (64.3%) vs. 53 of 112 (47.3%), p = 0.023 for oxytocin and dinoprostone groups, respectively.

Conclusions: Vaginal dinoprostone appears to be a relatively inefficient method of inducing labor compared with oxytocin in term pregnancies with PROM and unfavorable cervixes. However, dinoprostone may maintain uterine contractions as effectively as oxytocin once uterine contractions are established.

Keywords: dinoprostone; induction of labor; oxytocin; premature rupture of the membranes; prostaglandin E2.