section name header

Evidence summaries

Mifepristone for Induction of Labour

Oral mifepristone appears to be effective for inducing labour compared to placebo. Level of evidence: "B"

A network meta-analysis 3 assessed the relative effectiveness, safety and cost-effectiveness of labour induction methods. 611 trials were included. The interventions most likely to achieve vaginal delivery within 24 hours were intravenous oxytocin with amniotomy (posterior rank 2; 95% credible intervals (CI) 1 to 9) and higher-dose (HASH(0x2fcfe80) 50 µg) vaginal misoprostol (rank 3; 95% CI 1 to 6) (table T1). Compared with placebo, several treatments reduced the odds of caesarean section, but there were considerable uncertainty in treatment rankings. For uterine hyperstimulation, double-balloon catheter had the highest probability of being among the best 3 treatments, whereas vaginal misoprostol (HASH(0x2fcfe80) 50 µg) was most likely to increase the odds of excessive uterine activity.

Interventions for failure to achieve vaginal delivery within 24 hours

Active intervention vs placeboOdds ratio95% CI
i.v. oxytocin with amniotomy0.050.07 to 0.32
Vaginal misoprostol HASH(0x2fcfe80) 50 μg0.090.06 to 0.24
Titrated (low-dose) oral misoprostol solution0.100.07 to 0.29
Vaginal misoprostol < 50 μg0.110.09 to 0.32
Buccal/sublingual misoprostol0.110.05 to 0.19
Vaginal PGE2 pessary (normal release)0.110.04 to 0.16
Oral misoprostol tablet HASH(0x2fcfe80) 50 μg0.160.05 to 0.20
Double-balloon or Cook's catheter0.180.01 to 0.16
Foley catheter0.190.09 to 0.46
Mifepristone0.760.05 to 0.20

A Cochrane review [Abstract] 1 included 10 trials with a total of 1 108 women. Mifepristone treated women were more likely to be in labour or to have a favourable cervix within 48 and 96 hours of treatment than were placebo treated/no treatment women (48 hours: RR 2.41, 95% CI 1.70 to 3.42, 4 studies, n= 293; 96 hours: RR 3.40, 95% CI 1.96 to 5.92, 2 studies, n=144). They were less likely to need augmentation with oxytocin (RR 0.80, 95% CI 0.66 to 0.97; 5 studies, n=499). Mifepristone treated women were less likely to undergo caesarean section (RR 0.74, 95% CI 0.60 to 0.92; 9 studies, n=1 043), but more likely to have an instrumental delivery (RR 1.43, 95% CI 1.04 to 1.96; 7 studies, n=814). Women receiving mifepristone were less likely to undergo a caesarean section as a result of failure to induce labour (RR 0.40, 95% CI 0.20 to 0.80). Abnormal fetal heart rate patterns were more common after mifepristone treatment (RR 1.85, 95% CI 1.17 to 2.93), but there was no evidence of differences in other neonatal outcomes. There is insufficient information on the occurrence of uterine rupture/dehiscence in the reviewed studies.

Another Cochrane review [Abstract] 2 interventions for labour induction in outpatient settings. Women who received mifepristone were less likely to require additional induction agents (average RR 0.59, 95% CI 0.37 to 0.95; 4 studies; n=311, I²=74%).

Comment: The quality of evidence is downgraded by imprecise results (few patients and wide confidence intervals).

    References

    • Hapangama D, Neilson JP. Mifepristone for induction of labour. Cochrane Database Syst Rev 2009;(3):CD002865. [PubMed]
    • Vogel JP, Osoti AO, Kelly AJ et al. Pharmacological and mechanical interventions for labour induction in outpatient settings. Cochrane Database Syst Rev 2017;(9):CD007701. [PubMed]
    • Alfirevic Z, Keeney E, Dowswell T et al. Which method is best for the induction of labour? A systematic review, network meta-analysis and cost-effectiveness analysis. Health Technol Assess 2016;20(65):1-584. [PubMed]

Primary/Secondary Keywords