Landgren B M, Csemiczky G
Department of Obstetrics and Gynecology, Karolinska Hospital, Stockholm, Sweden.
Contraception. 1991 Feb;43(2):149-59. doi: 10.1016/0010-7824(91)90042-e.
The effects of follicular growth and hormonal indices of the deliberate omission of two low-dose combined oral contraceptives, a monophasic 130 micrograms ethinylestradiol + 150 micrograms desorgestrel) and a triphasic (30 micrograms ethinylestradiol + 50 micrograms levonorgestrel for 6 days, followed by 40 micrograms ethinylestradiol + 75 micrograms levonorgestrel for 5 days and 30 micrograms ethinylestradiol + 125 micrograms levonorgestrel for 10 days) combination during the first three days of one contraceptive pill cycle was studied in two groups of 10 women each. Follicular growth was followed by ultrasound scanning and plasma levels of estradiol, and progesterone were measured every other day until day 19 of the contraceptive pill cycle. In each group, ovulation occurred in one subject and 4 women reacted with follicular activity only, while 5 women on the monophasic and 3 on the triphasic formulation exhibited complete ovarian suppression. Two subjects on the triphasic preparation showed follicular growth followed by insufficient luteal function. Thus, the risk of escape ovulation when the pill-free interval is prolonged to 10 days in women taking low-dose combined oral contraceptive pills, is low (1/10).
研究了在一个避孕药周期的前三天故意漏服两种低剂量复方口服避孕药（单相制剂：130微克炔雌醇+150微克去氧孕烯；三相制剂：6天服用30微克炔雌醇+50微克左炔诺孕酮，随后5天服用40微克炔雌醇+75微克左炔诺孕酮，10天服用30微克炔雌醇+125微克左炔诺孕酮）对卵泡生长和激素指标的影响。每组10名女性，通过超声扫描监测卵泡生长情况，并每隔一天测量血浆雌二醇和孕酮水平，直至避孕药周期的第19天。每组中，一名受试者发生排卵，4名女性仅有卵泡活动反应，而5名单相制剂使用者和3名三相制剂使用者表现出完全的卵巢抑制。两名使用三相制剂的受试者出现卵泡生长但黄体功能不足。因此，服用低剂量复方口服避孕药的女性将无药间隔延长至10天时发生突破性排卵的风险较低（1/10）。
