Evaluation of the efficacy of labor induction with vaginal misoprostol in a low-risk pregnant women population

TL;DR

This study found that vaginal misoprostol successfully induces labor in most low-risk pregnant women, especially those with prior deliveries.

Contribution

The study identifies predictors of successful labor induction with vaginal misoprostol in low-risk pregnancies.

Findings

71.4% of low-risk pregnant women successfully achieved vaginal delivery after misoprostol induction.

Women with no previous deliveries had lower success rates, while those with one previous delivery had higher success.

Higher Bishop scores and fewer misoprostol tablets were associated with successful induction.

Abstract

The aim of this study was to evaluate the success rate and predictors of labor induction using vaginal misoprostol in a low-risk pregnant women population.

A prospective cohort study was carried out with 196 pregnant women. Groups 2 and 4 of the Robson Classification admitted for induction of labor with vaginal misoprostol (25 μg tablets every 6 h, up to 4 tablets, for a maximum of 24 h). The success of labor induction was considered the achievement of vaginal delivery. Binary logistic regression was used to determine the best predictors of successful induction of labor with vaginal misoprostol.

Of all the pregnant women analyzed, 140 (71.4%) were successful and 56 (28.6%) were unsuccessful. Pregnant women who achieved successful induction had a higher number of pregnancies (1.69 vs. 1.36, p=0.023), a higher number of deliveries (0.57 vs. 0.19, p<0.001), a higher Bishop score (2.0 vs. 1.38, p=0.002), and lower misoprostol 25 μg tablets (2.18 vs. 2.57, p=0.031). No previous deliveries [x2(1)=3.14, odds ratio (OR): 0.24, 95% confidence interval (CI): 0.10–0.57, R2 Nagelkerke: 0.91, p=0.001] and the presence of one previous delivery [x2(1)=6.0, OR: 3.40, 95% CI: 1.13–10.16, R2 Nagelkerke: 0.043, p=0.029] were significant predictors of successful induction of labor with vaginal misoprostol.

A high rate of labor induction success using vaginal misoprostol in a low-risk population was observed, mainly in multiparous and with gestational age>41 weeks. No previous delivery decreased the success of labor induction, while one previous delivery increased the success of labor induction.