Weisberg Edith, Merki-Feld Gabriele S, McGeechan Kevin, Fraser Ian S
Sydney Centre for Reproductive Health Research, Family Planning New South Wales, NSW 2131, Australia; University of Sydney, NSW 2006, Australia.
Clinic for Reproductive Endocrinology, Department Gynaecology, University Hospital, 8006 Zürich, Switzerland.
Contraception. 2015 Feb;91(2):121-6. doi: 10.1016/j.contraception.2014.10.006. Epub 2014 Oct 22.
To compare bleeding patterns for 12 months continuous use of a contraceptive ring [contraceptive vaginal ring (CVR)] and pill [combined oral contraceptive (COC)] on a menstrually signaled regimen and the effectiveness of 4 days "treatment withdrawal" to stop bleeding.
Women, 66 to each group, were randomized to continuous use of a CVR (15 mcg ethinyl estradiol/150 mcg etonogestrel) or a low-dose pill (20 mcg ethinyl estradiol/100 mcg levonorgestrel) for 360 days on a menstrually signaled regimen. Bleeding/spotting days, daily use of ring or pill, was recorded. Endpoint was the total number of bleeding/spotting days for each method over four 90-day reference periods (RP) plus the analysis of bleeding patterns using modified World Health Organization criteria.
There was a reduction in the mean (±S.D.) number of bleeding/spotting days from RP1 (CVR 14.2±10; pill 16.6±10.9) to RP4 (CVR 8.8±9.6; pill 8.8±9.1). Fifteen percent of CVR and 4% COC users experienced amenorrhea or infrequent bleeding throughout the study. Amenorrhea increased over time (RP1 vs. RP4: CVR 10% vs. 21% and COC 2% vs. 30%). Compliance with the menstrually signaled regimen was poor. Ceasing hormones for 4 days stopped a bleeding episode within 5 days in the majority of episodes and many stopped spontaneously.
Bleeding patterns with continuous use of the CVR and COC are similar and improve over 1 year of use. The unpredictability, but short duration, of bleeding episodes should be stressed during counseling.
This information for clinicians and women about breakthrough bleeding patterns with use of a CVR or combined pill over 12 months using a menstrually signaled regimen will give women an indication of what to expect with continuous use.
比较在月经提示方案下连续使用12个月避孕环[阴道避孕环（CVR）]和避孕药丸[复方口服避孕药（COC）]的出血模式，以及4天“停药治疗”止血的有效性。
每组66名女性被随机分配，在月经提示方案下连续360天使用CVR（15微克炔雌醇/150微克依托孕烯）或低剂量药丸（20微克炔雌醇/100微克左炔诺孕酮）。记录出血/点滴出血天数、每日使用避孕环或药丸的情况。终点指标是每种方法在四个9个 天参考期（RP）内出血/点滴出血的总天数，以及使用改良的世界卫生组织标准分析出血模式。
从参考期1（CVR 14.2±10；药丸16.6±10.9）到参考期4（CVR 8.8±9.6；药丸8.8±9.1），出血/点滴出血的平均（±标准差）天数有所减少。在整个研究过程中，15%的CVR使用者和4%的COC使用者出现闭经或出血不频繁。闭经随时间增加（参考期1与参考期4：CVR为10%对21%，COC为2%对30%）。对月经提示方案的依从性较差。在大多数情况下，停止激素治疗4天可在5天内停止出血发作，许多发作会自行停止。
连续使用CVR和COC的出血模式相似，且在使用1年后有所改善。在咨询过程中应强调出血发作的不可预测性，但持续时间较短。
这些关于临床医生和女性在月经提示方案下连续12个月使用CVR或复方药丸时突破性出血模式的信息，将使女性了解连续使用时的预期情况。
