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

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

A non-blinded, randomised, controlled trial.

A tertiary level, teaching Scottish Hospital.

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

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).

The number delivering vaginally within 24 hours of the induction.

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.

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