In most pregnancies that miscarry, arrest of embryonic or fetal development occurs some time (often weeks) before the
miscarriage occurs. Ultrasound examination can reveal abnormal findings during this phase by demonstrating anembryonic pregnancies or embryonic or
fetal death. Treatment before 14 weeks has traditionally been surgical but medical treatments may be effective, safe, and acceptable, as may be waiting for spontaneous
miscarriage.
OBJECTIVES: We searched the Cochrane Pregnancy and Childbirth Group Trials Register (30 November 2005).
SELECTION CRITERIA: Randomised trials comparing medical treatment with another treatment (e.g. surgical evacuation), or placebo, or no treatment for early pregnancy failure. Quasi-random studies were excluded.
DATA COLLECTION AND ANALYSIS: Data were extracted unblinded.
MAIN RESULTS: Twenty four studies (1888 women) were included. Vaginal
misoprostol hastens
miscarriage (complete or incomplete) when compared with placebo: e.g.
miscarriage less than 24 hours (two trials, 138 women, relative risk (RR) 4.73, 95% confidence interval (CI) 2.70 to 8.28), with less need for uterine
curettage (two trials, 104 women, RR 0.40, 95% CI 0.26 to 0.60) and no significant increase in
nausea or diarrhoea. Lower-dose regimens of vaginal
misoprostol tend to be less effective in producing
miscarriage (three trials, 247 women, RR 0.85, 95% CI 0.72 to 1.00) with similar incidence of
nausea. There seems no clear advantage to administering a 'wet' preparation of vaginal
misoprostol or of adding
methotrexate, or of using laminaria tents after 14 weeks. Vaginal
misoprostol is more effective than vaginal
prostaglandin E in avoiding surgical evacuation. Oral
misoprostol was less effective than vaginal
misoprostol in producing complete
miscarriage (two trials, 218 women, RR 0.90, 95% CI 0.82 to 0.99). Sublingual
misoprostol had equivalent efficacy to vaginal
misoprostol in inducing complete
miscarriage but was associated with more frequent diarrhoea. The two trials of
mifepristone treatment generated conflicting results. There was no statistically significant difference between vaginal
misoprostol and
gemeprost in the induction of
miscarriage for
fetal death after 13 weeks.
AUTHORS' CONCLUSIONS: Available evidence from randomised trials supports the use of vaginal
misoprostol as a medical treatment to terminate non-viable pregnancies before 24 weeks. Further research is required to assess effectiveness and safety, optimal route of administration and dose. Conflicting findings about the value of
mifepristone need to be resolved by additional study.