Goa Karen L, Warner Gregory T, Easthope Stephanie E
Adis International Inc., Langhorne, Pennsylvania 19047, USA.
Treat Endocrinol. 2003;2(3):191-206. doi: 10.2165/00024677-200302030-00005.
Ethinylestradiol 20 microg/day plus norelgestromin 150 microg/day have been formulated into a transdermal patch for hormonal contraception. The predominant mechanism of action for transdermal ethinylestradiol/norelgestromin (Ortho Evra, Evra) is inhibition of ovulation by suppression of gonadotropins. It suppresses follicular development, induces changes to the endometrium that reduce the probability of implantation, and increases the viscosity of cervical mucus, which may prevent sperm penetration into the uterus. Two large randomized, nonblind efficacy studies demonstrated that transdermal ethinylestradiol/norelgestromin was as efficacious in preventing pregnancy as oral triphasic ethinylestradiol/levonorgestrel or oral ethinylestradiol/desogestrel. A large, noncomparative study also showed transdermal ethinylestradiol/norelgestromin to have good contraceptive efficacy. Moreover, in the two comparative trials, women using transdermal ethinylestradiol/norelgestromin had higher rates of perfect compliance than women using oral contraception. Age did not affect the rate of perfect compliance in women using the transdermal ethinylestradiol/norelgestromin patch, whereas the rate of compliance reduced with younger age in oral contraceptive users. Pooled results from three efficacy studies found that 1.8% of patches were replaced as a result of complete detachment and 2.9% because of partial detachment. Physical exercise, water immersion, and living in a humid climate did not affect patch adhesion. Transdermal ethinylestradiol/norelgestromin was generally well tolerated in clinical trials. The most common menstrual disturbances were breakthrough bleeding/spotting and dysmenorrhea. The incidence of discontinuation of treatment because of an adverse event was < or = 3.2%, with the most common reason being application-site reactions.
Transdermal ethinylestradiol/norelgestromin offers a well tolerated, effective, reversible, and easy-to-use method of hormonal contraception with an increased likelihood of compliance relative to oral contraceptives.
乙炔雌二醇20微克/天加诺孕酯150微克/天已被制成用于激素避孕的透皮贴剂。透皮乙炔雌二醇/诺孕酯（欧然埃弗拉，埃弗拉）的主要作用机制是通过抑制促性腺激素来抑制排卵。它抑制卵泡发育，诱导子宫内膜发生变化以降低着床概率，并增加宫颈黏液的黏稠度，这可能会阻止精子进入子宫。两项大型随机、非盲性疗效研究表明，透皮乙炔雌二醇/诺孕酯在预防妊娠方面与口服三相乙炔雌二醇/左炔诺孕酮或口服乙炔雌二醇/去氧孕烯一样有效。一项大型非对照研究也表明透皮乙炔雌二醇/诺孕酯具有良好的避孕效果。此外，在两项对照试验中，使用透皮乙炔雌二醇/诺孕酯的女性完全依从率高于使用口服避孕药的女性。年龄对使用透皮乙炔雌二醇/诺孕酯贴剂的女性的完全依从率没有影响，而口服避孕药使用者的依从率随年龄减小而降低。三项疗效研究的汇总结果发现，1.8%的贴剂因完全脱落而被更换，2.9%因部分脱落而被更换。体育锻炼、水浸以及生活在潮湿气候中均不影响贴剂的黏附。透皮乙炔雌二醇/诺孕酯在临床试验中总体耐受性良好。最常见的月经紊乱是突破性出血/点滴出血和痛经。因不良事件而停药的发生率≤3.2%，最常见的原因是用药部位反应。
透皮乙炔雌二醇/诺孕酯提供了一种耐受性良好、有效、可逆且易于使用的激素避孕方法，相对于口服避孕药，其依从可能性增加。
