The effect of propranolol plus misoprostol with misoprostol alone on induction of labor

One of the important issues in obstetrics is labor induction in the inappropriate conditions of the cervix. Misoprostol improves the condition of the cervix and shortens the duration of the labor and help in delivery sucess. Some studies have been published on the effect of propranolol on labor process in favor of shortening the labor. Therefore, this study was performed with aim to compare the effect of propranolol plus misoprostol with misoprostol alone on labor induction.

This double-blind clinical trial study was performed from November 2017 to September 2019 on 70 pregnant women referred to the maternities of Mashhad University Hospitals. The subjects were randomly divided into two groups. One group received 25 micrograms of sublingual misoprostol every 4-6 hours up to 6 doses plus a placebo capsule, and the other group received misoprostol with the same dose and method of the first group plus two doses of oral 20mg Propranolol tablet with interval of 4 hours. The interval between drug administration with onset of effective contractions, and onset of active phase and delivery were evaluated and compared in the two groups. Data were analyzed by SPSS statistical software (version 16). T-test and chi-square test were used to compare the groups, and equivalent non-parametric methods were used if necessary.

Mean interval of induction onset to effective contractions did not show any significant difference between the two groups (P=0.394). There was no significant difference between the two groups in the mean interval of induction onset to 4cm dilatation (P=0.82) and the mean interval of induction onset to delivery (P=0.108). Delivery complications showed no significant difference between the two groups (P=0.397). There was no significant difference between the two groups in the mean first and fifth minute Apgar score (P=0.715 and P=0.819, respectively).

Propranolol use had no effect on decreasing the induction to delivery interval and reducing cesarean rate. Also, it didn’t cause changes in neonatal outcomes and maternal complications. There were no side effects of propranolol tablets, including bradycardia, hypotension, and drowsiness.