A scoring system for induction of labor using prostaglandin E2 vaginal tablets

A randomized controlled trial was carried out in order to establish the efficacy of a scoring system for calculating the dose of vaginal prostaglandin E2 tablets for the induction of labor. One hundred ten women were included in the study. The patients received a dose of prostaglandin E2 calculated according to a scoring system based on the Bishop's score, or the standard dose of 3 mg repeated 6 h later if labor did not start. The percentage of inductions achieved was the same with both regimens (92.7%). The mean total dose used in the scoring system-group (2.7 mg) was significantly lower than that used in the 3-mg group (3.5 mg, P less than 0.025). Thirty-seven of 55 women receiving the scoring dose delivered with amounts of 2.5 mg prostaglandin E2 or less. Three cases of uterine hyperstimulation were observed in the 3-mg group whereas no cases were observed in the scoring group. The scoring system is proposed as a method for calculating the dose of vaginal prostaglandin E2 for induction of labor and minimizing the risk of overdosage.