A Comparative Study of the Efficacy and Safety of Two Misoprostol Regimens for Labour Induction at Term in Delta State: A Two-centre Triple-blind Randomised Controlled Trial.

Abstract

The optimal administration of misoprostol for induction of labour (IOL), including its efficacy and safety, remains an issue in obstetrics. This study aimed to evaluate and compare the efficacy and safety of hourly Titrated oral misoprostol (TOM) doses and four-hourly vaginal misoprostol (VM) for labour induction at term in a multi-centre setting in Delta State, Nigeria. A total of 260 singleton term pregnancies were randomised using computer-generated numbers and opaque envelopes. The study compared the efficacy of hourly titrated oral misoprostol solution against four-hourly 25 mcg vaginal tablets. The primary outcome measure was the vaginal delivery rate within 24 h. The secondary outcomes included duration of active labour, time from induction initiation to delivery, caesarean section rate, total oxytocin dosage, presence of foetal heart rate abnormalities, abnormal uterine contractions and uterine rupture. Data analysis, utilising Chi-square and Student's t -tests, was conducted using IBM SPSS Statistics for Windows (Version 28.0; IBM Corp., Armonk, NY, USA). Women in the hourly titrated oral misoprostol group demonstrated a significantly higher rate of vaginal delivery within 24 h (96.2%) compared to the four-hourly VM group (83.1%) ( P < 0.338). Significant differences were observed between the groups in the rates of abnormal uterine contractions ( χ2 = 5.969, P = 0.015), abnormal foetal heart rate patterns ( χ2 = 6.660, P = 0.018) and caesarean section rates ( χ2 = 5.426, P = 0.015). No cases of uterine rupture occurred in either group during the study period. This study demonstrated comparable efficacy between hourly titrated oral misoprostol and four-hourly VM for labour induction. However, hourly titrated oral misoprostol exhibited a more favourable safety profile, as regards abnormal uterine contractions, foetal heart rate patterns and caesarean section rate.