Sublingual compared with oral misoprostol in term labour induction: a randomised controlled trial

Objective To compare the efficacy and patient acceptability of 50 mug of sublingual misoprostol with 100 mug of oral misoprostol in the induction of labour at term. Design Non-blinded randomised comparative trial. Setting Tertiary level UK Hospital. Sample Two hundred and fifty women at term with indications for labour induction. Methods Fifty micrograms of sublingual misoprostol or 100 mug of oral misoprostol was administered every four hours after random allocation, to a maximum of five doses. Main outcome measures Number of patients delivering vaginally within 24 hours of the induction, mode of delivery, neonatal outcomes and patient acceptability. Results There was no significant difference in the number of women delivering vaginally within 24 hours of the induction in the sublingual group as compared with the oral group (62.8% vs 59%, RR 1.1, 95% Cl 0.6-2.1), or in the mean induction to delivery time (21.8 vs 24.1 h, mean difference 2.3 h 95% CI -2.2 to +6.7). There was no difference in the uterine hyperstimulation rates (1.6% in both groups), operative delivery rates or neonatal outcomes. In the sublingual group, 92.6% found the induction acceptable with 15.8% finding the tablets with an unpleasant taste, while in the oral group it was 96.9% and 4%, respectively. More patients in the oral group thought that they would consider the same method of induction again as compared with the sublingual group (58.6% vs 40%, RR 1.4, 95% Cl 1.04-1.9). Conclusion Fifty micrograms of sublingual misoprostol every four hours has the same efficacy and safety profile as compared with 100 mug orally, but the oral route might be preferred by women.