RESUMO
TRIAL DESIGN: A randomised, parallel-group, double-blind, placebo-controlled multicentre study with health economic and nested qualitative studies to determine if mifepristone (Mifegyne®, Exelgyn, Paris, France) plus misoprostol is superior to misoprostol alone for the resolution of missed miscarriage. METHODS: Women diagnosed with missed miscarriage in the first 14 weeks of pregnancy were randomly assigned (1 : 1 ratio) to receive 200 mg of oral mifepristone or matched placebo, followed by 800 µg of misoprostol 2 days later. A web-based randomisation system allocated the women to the two groups, with minimisation for age, body mass index, parity, gestational age, amount of bleeding and randomising centre. The primary outcome was failure to pass the gestational sac within 7 days after randomisation. The prespecified key secondary outcome was requirement for surgery to resolve the miscarriage. A within-trial cost-effectiveness study and a nested qualitative study were also conducted. Women who completed the trial protocol were purposively approached to take part in an interview to explore their satisfaction with and the acceptability of medical management of missed miscarriage. RESULTS: A total of 711 women, from 28 hospitals in the UK, were randomised to receive either mifepristone plus misoprostol (357 women) or placebo plus misoprostol (354 women). The follow-up rate for the primary outcome was 98% (696 out of 711 women). The risk of failure to pass the gestational sac within 7 days was 17% (59 out of 348 women) in the mifepristone plus misoprostol group, compared with 24% (82 out of 348 women) in the placebo plus misoprostol group (risk ratio 0.73, 95% confidence interval 0.54 to 0.98; p = 0.04). Surgical intervention to resolve the miscarriage was needed in 17% (62 out of 355 women) in the mifepristone plus misoprostol group, compared with 25% (87 out of 353 women) in the placebo plus misoprostol group (risk ratio 0.70, 95% confidence interval 0.52 to 0.94; p = 0.02). There was no evidence of a difference in the incidence of adverse events between the two groups. A total of 42 women, 19 in the mifepristone plus misoprostol group and 23 in the placebo plus misoprostol group, took part in an interview. Women appeared to have a preference for active management of their miscarriage. Overall, when women experienced care that supported their psychological well-being throughout the care pathway, and information was delivered in a skilled and sensitive manner such that women felt informed and in control, they were more likely to express satisfaction with medical management. The use of mifepristone and misoprostol showed an absolute effect difference of 6.6% (95% confidence interval 0.7% to 12.5%). The average cost per woman was lower in the mifepristone plus misoprostol group, with a cost saving of £182 (95% confidence interval £26 to £338). Therefore, the use of mifepristone and misoprostol for the medical management of a missed miscarriage dominated the use of misoprostol alone. LIMITATIONS: The results from this trial are not generalisable to women diagnosed with incomplete miscarriage and the study does not allow for a comparison with expectant or surgical management of miscarriage. FUTURE WORK: Future work should use existing data to assess and rank the relative clinical effectiveness and safety profiles for all methods of management of miscarriage. CONCLUSIONS: Our trial showed that pre-treatment with mifepristone followed by misoprostol resulted in a higher rate of resolution of missed miscarriage than misoprostol treatment alone. Women were largely satisfied with medical management of missed miscarriage and would choose it again. The mifepristone and misoprostol intervention was shown to be cost-effective in comparison to misoprostol alone. TRIAL REGISTRATION: Current Controlled Trials ISRCTN17405024. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 68. See the NIHR Journals Library website for further project information.
Miscarriage is a common complication of pregnancy, affecting approximately one in four women. Sometimes, medical treatment (i.e. tablets) may be offered to start or speed up the miscarriage process in order for the womb to empty itself. A drug called misoprostol (a tablet that makes the womb contract) is currently recommended for this treatment. However, the addition of another drug called mifepristone [a tablet that reduces pregnancy hormones (Mifegyne®, Exelgyn, Paris, France)] might help the miscarriage to resolve more quickly. Therefore, we carried out the MifeMiso trial to test if mifepristone plus misoprostol is more effective than misoprostol alone in resolving miscarriage within 7 days. Women were randomly allocated by a computer to receive either mifepristone or placebo, followed by misoprostol 2 days later. Neither the women nor their health-care professionals knew which treatment they received. Some women also talked to the researchers about their experiences of taking part in the study. In total, 711 women were randomised to receive either mifepristone plus misoprostol or placebo plus misoprostol. Overall, 83% of women who received mifepristone plus misoprostol had miscarriage resolution within 7 days, compared with 76% of the women who received a placebo plus misoprostol. Surgery was required less often in women who received mifepristone plus misoprostol: 17% of women who received it required surgery, compared with 25% of women who received the placebo. Treatment with mifepristone did not appear to have any negative effects. Treatment with mifepristone plus misoprostol was more cost-effective than misoprostol alone, with an average saving of £182 per woman. Having taken part in the study, most women would choose medical management again and would recommend it to someone they knew who was experiencing a miscarriage.