A randomised comparison of oral misoprostol and vaginal prostaglandin E2 tablets in labour induction at term.

OBJECTIVE: To compare the efficacy of 100 microg of oral misoprostol with 3 mg prostaglandin E2 vaginal tablets in term labour induction.

DESIGN: A non-blinded, randomised, controlled trial.

SETTING: A tertiary level, teaching Scottish Hospital.

POPULATION: Two hundred women at term with indications for labour induction and modified Bishop's cervical score of less than 8.

METHODS: The women were randomly allocated to receive either 100 microg of misoprostol orally (which could be repeated 4 hourly to a maximum of five doses if indicated), or a 3 mg tablet of prostaglandin E2 vaginally (which could be repeated in 6 hours, according to routine departmental protocol).

MAIN OUTCOME MEASURE: The number delivering vaginally within 24 hours of the induction.

RESULTS: Seventy-five women delivered vaginally in the misoprostol group and 73 in the PGE2 group. Of these, 50.7% in the misoprostol group and 54.8% in the PGE2 group delivered within 24 hours of the induction (RR 0.92, 95% CI 0.7 to 1.3). More women in the misoprostol group were given oxytocin, but this was not statistically significant (60%vs 47%, RR 1.3, 95% CI 0.98 to 1.7). Two women in the misoprostol group had uterine hyperstimulation. The neonatal outcomes were not significantly different in the two groups. There was a pound 1100 saving on direct drug costs in the misoprostol group.

CONCLUSIONS: Oral misoprostol (100 microg) has similar efficacy to vaginal PGE2 tablets, and may be an option to consider for term labour induction.