Medical abortion at 57 to 63 days' gestation with a lower dose of mifepristone and gemeprost. A randomized controlled trial.
OBJECTIVE
To compare the abortifacient efficacy and side-effects of 200 mg and 600 mg of mifepristone, followed by gemeprost 1 mg vaginally, at 57 to 63 days' gestation.


METHODS
Double-blind, randomized controlled trial.


METHODS
Ten international centers.


METHODS
Eight hundred and ninety-six healthy women requesting medical abortion.


METHODS
Participants were randomly assigned to receive a single oral dose of mifepristone of either 200 mg or 600 mg followed in 48 h by gemeprost 1 mg vaginally. The allocation sequence was concealed by using a central pharmacy, and double masking was maintained throughout the study.


METHODS
Complete abortion rate was the principal outcome measure. We also evaluated the incidence of side-effects and time to abort.


RESULTS
The complete abortion rate with the lower dose of mifepristone was similar to that with the higher dose (92.4% vs. 91.7%). The relative risk of failure to achieve a complete abortion with the 200 mg dose compared to 600 mg dose was 0.9 (95% CI 0.6-1.4). The timing of the abortion and the incidence of side-effects were comparable in both groups, with the exception of reported nausea at one-week follow-up which was reported more frequently by women in the higher-dose group.


CONCLUSIONS
The 200 mg dose of mifepristone is equally as effective as the 600 mg dose in the antiprogestogen-prostaglandin regimen for pregnancy termination. With vaginal gemeprost, the abortifacient efficacy of the regimen remains high at 57-63 days' gestation.
D000020:Abortifacient Agents, Nonsteroidal / Q000008:administration & dosage*; D000021:Abortifacient Agents, Steroidal / Q000008:administration & dosage*; D000028:Abortion, Induced; D000282:Administration, Intravaginal; D000284:Administration, Oral; D000328:Adult; D000527:Alprostadil / Q000008:administration & dosage* / Q000031:analogs & derivatives*; D002681:China; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005060:Europe; D005260:Female; D005846:Georgia (Republic); D006723:Hong Kong; D006801:Humans; D007194:India; D015735:Mifepristone / Q000008:administration & dosage*; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D017524:Slovenia; D016896:Treatment Outcome; D014481:United States
D000020:Abortifacient Agents, Nonsteroidal; D000021:Abortifacient Agents, Steroidal; D015735:Mifepristone; C021182:gemeprost; D000527:Alprostadil