Succes of labor induction methods in obese women: A scoping review

Background Obese women require labor induction more often than lean women, but induction in this group is less often successful, and the best method has not been established. The aim of this scoping review was to examine available evidence of the success of different induction methods in obese women. Methods We searched PubMed, Embase and Web of Science as well as bibliographies for studies of labor induction in obese women. Search terms included “obesity”, “induction of labor”, “cesarean section”, “misoprostol”, “amniotomy” and “mechanical induction”. Studies reporting outcomes of specific methods of labor induction in obese women were included, with cesarean section as the primary outcome. Results The search identified 644 studies, of which 27 were included, most of these were retrospective. There was a tendency towards more doses of misoprostol needed for the obese, but no benefit of using 50µg compared to 25µg oral misoprostol. Vaginal delivery rates rose with more days of misoprostol administration. Vaginal misoprostol seemed to be more efficient in the obese compared to oral misoprostol, with shorter time to delivery and more vaginal deliveries, but it might also carry a higher risk of uterine hyperstimulation. Evidence of the efficiency of Foley or balloon catheters in the obese was insufficient. Amniotomy led to more cesarean sections if performed at less than 4 cm of cervical dilation Conclusion The available evidence indicates that vaginal misoprostol might be more efficient than oral in obese parturients, and that obese women might have a better chance of achieving vaginal labor after multiple days of induction. Amniotomy at less than 4 cm of cervical dilation leads to higher risk of cesarean section in the obese. There is a lack of randomized trials examining labor induction in the obese.