Comparison of 25 µg Vaginal Misoprostol Versus Dinoprostone Gel for Induction of Labor in Term Prelabor Rupture of Membranes: A Retrospective Record-Based Observational Study

Background and objective: Prelabor rupture of membranes (PROM) at term occurs in 8-10% of pregnancies, and a long latency period is associated with infection in both the mother and the newborn.In women with an unfavorable cervix, cervical ripening and induction of labor are widely used with prostaglandin analogs.However, the preferred agent in women with term PROM remains unclear.This study compared the efficacy and safety of 25 µg vaginal misoprostol (prostaglandin E1) and dinoprostone (prostaglandin E2) gel in women with term PROM.Materials and methods: This was a record-based, comparative, observational study with a retrospective design conducted at a tertiary care teaching hospital in West India over 12 months.Records of 200 women with term PROM (≥37 weeks), singleton cephalic pregnancy, and an unfavorable cervix (Bishop's score ≤6) were reviewed.The primary outcome was the induction-to-delivery interval and the proportion of vaginal deliveries within 24 hours.Secondary outcomes included change in Bishop score at six hours, oxytocin dose, interval from induction to active labor, need for oxytocin augmentation, mode of delivery, and maternal and neonatal safety outcomes.An independent-samples t-test was employed for continuous variables, and chisquare or Fisher's exact test was used for categorical variables; p < 0.05 was considered significant.Results: The two groups did not differ in maternal age, parity, PROM duration, or baseline Bishop score.The mean Bishop score at six hours was significantly higher in the misoprostol group (5.68 ± 1.31 vs 4.78 ± 1.26; p < 0.001).The mean induction-to-active-labor interval (6.80 ± 1.58 vs 8.19 ± 2.06 hours; p < 0.001) and the induction-to-delivery interval (11.81 ± 3.06 vs 13.78 ± 3.99 hours; p < 0.001) were significantly shorter with misoprostol, which also required fewer doses (1.62 ± 0.63 vs 1.91 ± 0.67; p = 0.002) and less oxytocin augmentation (16 (16.0%) vs 46 (46.0%); p < 0.001).No significant differences were observed in the proportion of vaginal deliveries within 24 hours (92 (92.0%) vs 94 (94.0%); p = 0.780) or cesarean deliveries (8 (8.0%) vs 6 (6.0%); p = 0.780).The groups did not differ in uterine hyperstimulation (5% vs 2%), abnormal fetal heart rate (8% vs 6%), postpartum hemorrhage (4% vs 5%), mean birth weight, or NICU admission (4% vs 0%).Conclusions: 25 µg vaginal misoprostol was associated with more effective cervical ripening and shorter time to delivery than dinoprostone gel, with fewer doses and a lower rate of oxytocin use, similar cesarean rates, and comparable maternal and neonatal safety.The use of low-dose vaginal misoprostol may represent a practical alternative to dinoprostone gel in term PROM.