目的探索米非司酮合并米索前列醇（米索）终止１０～１６周妊娠最佳剂量及最佳给药途径。方法将来自上海２４所医院的２００７例孕１０～１６周要求药物终止妊娠的妇女，随机分成４种不同的治疗组。组Ⅰ：５１１例，米非司酮７５ｍｇ每天１次，连服２天（总量１５０ｍｇ），第３天晨口服米索０．６ｍｇ，每３～４小时重复１次，最多３次；组Ⅱ：４９１例，米非司酮１００ｍｇ每天１次，连服２天（总量２００ｍｇ），米索用法同组Ⅰ；组Ⅲ：５１９例，米非司酮用法同组Ⅰ，第３天晨阴道内放置米索０．６ｍｇ，每１２小时重复１次，最多３次；组Ⅳ：４８６例，米非司酮用法同组Ⅱ，米索用法同组Ⅲ。结果４组２４小时内的流产成功率分别为８８．６％、８９．４％、９０．９％和９４．０％。组Ⅳ的成功率明显高于组Ⅰ和组Ⅱ。２４小时内流产成功者米索的用量，阴道给药者比口服给药者明显减少（Ｐ＜０．００１），胃肠道副反应发生率也明显降低（Ｐ＜０．０５）。结论口服米非司酮２００ｍｇ合并阴道放置米索，是较好的药物终止１０～１６周妊娠的方法，可作为一种常规方法推荐在临床应用。 Objective To explore the optimal dose of mifepristone combined with misoprostol (misoprostol) to terminate the pregnancy of 10 ~ 16 weeks and the optimal route of administration. Methods A total of 40 pregnancies from 10 pregnant women in Shanghai’s 24 hospitals were enrolled in this study. Pregnant women were randomly assigned to 4 different treatment groups. Group Ⅰ: 511 cases, mifepristone 75mg once daily for 2 days (total 150mg), on the 3rd day morning oral misoprostol 0.6mg, once every 3 to 4 hours, up to 3 times; group Ⅱ: 491 cases, mifepristone 100mg once daily, even for 2 days (total 200mg), the use of misoprostol group Ⅰ; group Ⅲ: 519 cases, mifepristone use the same group Ⅰ, the first 3 days Intravaginal placement of misoprostol 0.6mg, repeated once every 12 hours, up to 3 times; Group Ⅳ: 486 cases, mifepristone use the same group Ⅱ, misoprostol group Ⅲ. Results The success rates of abortion within 24 hours in 4 groups were 88.6%, 89.4%, 90.9% and 94.0% respectively. The success rate of group Ⅳ was significantly higher than that of group Ⅰ and group Ⅱ. The amount of misoprostol that was successfully aborted in 24 hours was significantly lower in vaginal administration than in oral administration (P <0.001). The incidence of gastrointestinal side effects was also significantly reduced (P <0.05). Conclusions Oral mifepristone 200mg combined with vaginal misoprostol is a good method for stopping the pregnancy of 10 ~ 16 weeks and can be recommended as a routine method for clinical application.