Safety and efficacy of an oral misoprostol standard-dose regimen vs a low-dose regimen for induction of labour in Papua New Guinean women: An open-label randomised controlled trial.

Abstract

Oral misoprostol is widely used for induction of labour (IOL) in developing countries because of its many advantages. However, limited data exist concerning its safety and efficacy when lower doses are used. To determine the safety and efficacy of a low-dose oral misoprostol regimen (commencing at 12μg) compared to a standard-dose regimen (commencing at 25μg) in Papua New Guinea (PNG) women undergoing IOL. This was an open-label non-inferiority randomised controlled trial conducted at a provincial hospital in PNG. Women with singleton pregnancies ≥36weeks with cephalic presentation and a Bishops score of <6, requiring IOL were enrolled. Both regimens were incremented second-hourly to a maximum required dose within 24h or until commencement of labour. The primary outcome was the proportion of women who delivered within 24h of drug administration without any severe adverse events. Of the 262 women induced (130 standard-dose vs 132 low-dose), rates of successful induction were high for both regimens (120/130 (92%) vs 118/132 (89%); P=0.52). Fourteen women (11%) in the standard-dose regimen and 20 (15%) in the low-dose regimen had severe adverse events. There was no significant difference in the safety profile of the two regimens (106/130 (82%) vs 98/132 (74%); P=0.18). The induction-to-delivery time was significantly shorter in the standard-dose arm (15.2±8.7h vs 18.0±9.1h; P=0.01). The standard-dose regimen for IOL has greater efficacy in reducing induction-to-delivery time compared to the low-dose regimen. There was no significant difference in the number of adverse events between the two regimens.