每周口服米非司酮避孕的临床研究

Study on Weekly Administration of Mifepristone for Contraception

目的:研究每周一次口服米非司酮25mg或50mg用于常规避孕的可行性。方法:志愿参加避孕研究的健康妇女共33例,随机分为二组,自月经d2-3口服米非司酮,每例观察6个周期。A组(16例)每周口服米非司酮25mg;B组(17例)每周口服50mg。另在A组、B组中各选2例,每例服药前1个周期及服药后2-6个周期间,于黄体中期各取子宫内膜共2次作自身对照,测定子宫内膜形态学改变,应用免疫组化法检测基质金属蛋白酶(MMP)-9和MMP-26的表达。结果:A组共服药50个周期,1例妊娠,4例闭经,1例妇女经量极少;B组共服药81个周期,无1例妊娠,5例闭经,4例经期仅点滴出血。服药后与服药前比较内膜明显变薄,主要表现为基质和腺体发育不同步,大部分腺上皮分泌活动不明显。与对照周期相比,服药后二组MMP-9和MMP-26在子宫内膜腺上皮和基质细胞的表达均显著降低。结论:每周一次口服米非司酮(25mg或50mg)妇女的月经周期改变较大,临床避孕效果理想。每周口服50mg米非司酮可能是比较合适的剂量。但闭经率较高,且闭经的出现不可预测,妇女对其的可接受性较差。

Objective： To study whether the weekly administration of mifepristone （25 mg or 50 mg） was sufficient to contraception. Methods： Thirty-three women were randomly allocated to take mifepristone 25 mg （group A, 16 cases） or 50 mg （group B, 17 cases） doses once weekly starting on cycle d 2-3 for 6 cycles, they were healthy, fertile, sexually active female volunteers. An endometrial biopsy was collected in the mid-luteal phase in the control cycle and in the 2-6 treatment cycles and morphologic changes of endometrium were analyzed. Results： There were 1 pregnancy out of 50 cycles in group A, 4 amenorrhea; no pregnancy out of 81 cycles in group B, but 5 amenorrhea. The endometrial thickness was decreased significantly compared with that before the administration, the endometrial development was asynchronous and glandular diameter was reduced. The expressions of MMP-9 and MMP-26 in endometrial tissue of treatment cycles were lower than those of the control cycles. Conclusion： Administration of mifepristone 25 mg or 50 mg changes menstruate to a certain degree. The clinical contraceptive effectiveness is good, but the rate of amenorrhea is too high to widely be accepted.