A comparison of two dosing regimens of vaginally administered misoprostol for cervical ripening and induction of labour at term: A randomized controlled trial

Abstract

Background: The use of misoprostol in induction of labour has become established, but there exist wide variations in the dosing regimen.
Objective: The aim of this study was to compare the efficacy and safety of two regimens of intravaginal misoprostol for cervical ripening and labour induction at term.
Method: This prospective randomized clinical trial was conducted on 130 pregnant women at term in Aminu Kano Teaching Hospital, Kano, Nigeria. Those who fulfilled the criteria were randomized into 2 groups to receive intravaginal misoprostol tablets for 24 hours. Study group (A) received 4 hourly 25 µg misoprostol and Control group (B) 6 hourly 50 µg of misoprostol. Student t test, chi-square and Fisher Exact test were used to compare variables. P< 0.05 was considered statistically significant.
Results: Both regimens were effective in cervical ripening and induction of labour with 93.8% and 98.5% achieving vaginal deliveries for 25 µg and 50 µg groups respectively. Oxytocin need was significantly higher (p<0.001) in group A (76.9%) compared to group B (23.1%). The Mean induction- delivery interval in hours was significantly shorter (p< 0.001) in group B (19.31±6.91) compared to group A (25.57±7.25). The percentage of women who delivered within 24 hours of commencement of induction was significantly higher (p= 0.002) in group B. There was no difference in the modes of deliveries in both groups (p =0.074). Tachysystole developed in two and three women in group A and B respectively. There were no significant differences between the two groups in neonates with Apgar score < 7 at 1 minute, Apgar score < 7 at 5 minutes, nor the proportion admitted to NICU. There was no difference in the incidence of adverse maternal effects in each group with p- values > 0.05.
Conclusion: The mean induction-vaginal delivery interval and the number of women who delivered within 24 hours were better in 50µg group than 25µg group with no statistical significant difference in mode of deliveries, maternal and neonatal outcomes.