A randomised controlled trial of low-dose misoprostol and dinoprostone vaginal pessaries for cervical priming

Abstract

Objective: We studied the efficacy of 25-microg misoprostol pessaries as either single or double dose compared with a 3-mg dinoprostone pessary for cervical priming.

Design and setting: A randomised controlled trial in Singapore.

Population: One hundred and seventy-one women with term pregnancies and modified Bishop scores (mBS) < or =6 from 2003 to 2004.

Method: Patients were randomised to single misoprostol dose, double misoprostol dose or the current dinoprostone regimen.

Main outcome measures: Primary outcome was number of women who achieved favourable mBS >6 or active labour by day 2. Secondary outcomes were time interval from insertion to delivery, cardiotocographic abnormalities, delivery and neonatal outcome.

Results: More women in the misoprostol double-dose group (96.6%) and dinoprostone group (93%) achieved the primary outcome compared with the single-dose group (77.8%) (P = 0.003 and P = 0.03, respectively). There was no difference in secondary outcomes. More multiparous women achieve primary outcome compared with nulliparous women (odds ratio 0.21, 95% confidence interval 0.06-0.77).

Conclusion: Double-dose misoprostol 25 microg is as effective as dinoprostone 3 mg inserts for cervical priming; both are more efficacious than a single-dose misoprostol pessary. Parity prognosticates the success of induction.