[Termination of 10-16 weeks's gestation with mifepristone plus misoprostol: a multicentre randomized clinical trial]

To find out the optimal regimen of mifepristone in combination with misoprostol for termination of 10-16 week's gestation.

A randomized comparative study in 2,007 women requesting medical abortion at 10-16 week's gestation from 24 hospitals was conducted in Shanghai. Women were randomly divided into 4 groups. In group I (n = 511) women took mifepristone 75 mg orally per day for 2 days (total dose 150 mg), and 48 hours later misoprostol 0.6 mg orally every 3-4 hours for 3 times; group II (n = 491) mifepristone 100 mg orally per day for 2 days (total dose 200 mg) and 48 hours later same dose of misoprostol were taken as in group I; group III (n = 519) same dose of mifepristone as in group I and 48 hours later misoprostol given vaginally every 12 hours for 3 times; group IV (n = 486) same dose of mifepristone as in group II and 48 hours later same dose of misoprostol vaginally as in group III.

The successful abortion rate from group I to group IV were 88.6%, 89.4%, 90.9% and 94.0% respectively. The successful abortion rate of group IV was higher than that in group I and II with significant differences (P < 0.05). The average dose of misoprostol by vaginal route in successful case was much lower than that by oral (P < 0.01), and the rate of side effects was much lower by vaginal too.

Mifepristone taken 200 mg orally plus misoprostol vaginally is an optimal method for termination of 10-16 week's gestation.