Labor Induction with 50 μg Vaginal Misoprostol: Can We Reduce Induction-Delivery Intervals Safely?

Objective: To compare the efficacy and safety profile of two methods of labor induction i.e., intracervical dinoprostone gel (0.5 mg 8 h) and misoprostol (50 μg 4 h) for induction of labor in women with a poor Bishop's score.

Design: Observational study.

Study Period: January 1st, 2009 to December 31st, 2010.

Population: A total of 329 women with unfavorable cervices induced at or near term.

Methods: Two cervical ripening agent study arms were used: dinoprostone gel (193 women) and misoprostol (137 women).

Main Outcome Measures: Induction to delivery interval, cesarean section, incidence of meconium stained liquor, FHR pattern, incidence of uterine hyperstimulation, and neonatal outcomes.

Results: The induction to delivery interval was significantly shorter in the misoprostol group as compared to the dinoprostone group (p < 0.001). There was no difference in cesarean section rates between the two groups (dinoprostone gel 43 %; misoprostol 33 %; p = 0.144). The incidence of non-reassuring fetal heart rate pattern, meconium stained liquor, and uterine hyperstimulation were equivalent in both the groups (p = 0.529; 0.733; and 0.321, respectively). The neonatal outcomes in both the groups were comparable in terms of Apgar scores at birth (p = 0.160) and NICU admissions (p = 0.951).

Conclusions: Labor induction in women with unfavorable cervices results in high caesarean section rates. However, the use of misoprostol significantly reduces the induction to delivery interval, without adversely affecting the caesarean section rates and neonatal outcomes. Hence it may become a cost-effective alternative to dinoprostone gel in resource-poor settings like India.