Xiao B L, Zhou L Y, Zhang X L, Jia M C, Luukkainen T, Allonen H
National Research Institute for Family Planning, Beijing, China.
Contraception. 1990 Apr;41(4):353-62. doi: 10.1016/0010-7824(90)90035-t.
Intrauterine devices releasing 20 micrograms/day levonorgestrel were inserted in 10 women (ages 25-34). Bleeding and spotting patterns were recorded on a menstrual card during one year of follow-up. Blood samples were collected for radioimmunoassays of LH, estradiol (E2), progesterone (P) and levonorgestrel (LNG) and for sex hormone binding globulin (SHBG) 3 times a week during the 1st month of use, and twice a week during the 6th and 12th treatment months. Among the 10 women, two experienced irregular cycles with prolonged intermenstrual spotting, four had amenorrhea in the latter part of treatment months, while the other four had regular cycles. According to the serum levels of E2 and P, the hormone profiles were divided into four types of reaction: A) anovulatory, B) anovulatory but with high follicular activity, C) ovulatory but with luteal insufficiency, and D) ovulatory. Among the 29 treatment cycles, there were 10 D-type, 3 C-type, 13 B-type and 3 A-type of ovarian reactions: 44.8% of the cycles were ovulatory (C + D) and 55.2% were anovulatory (A + B). In general, serum levels of levonorgestrel were low in ovulatory cycles and were high in anovulatory cycles. The difference was statistically significant. There were marked individual differences. The decline of serum LNG from the 1st (492 pmol/l) to the 6th (320 pmol/l) treatment months was 34.9% on average. The amenorrheic cycles coincided mostly with the hormonal profile of ovulatory types, which indicated that the cause of amenorrhea is due to the local effect of levonorgestrel on the endometrium. The levonorgestrel levels were significantly correlated with serum SHBG, r = 0.8856, p less than 0.001, and with E2, r = 0.4661, p less than 0.05.
将每日释放20微克左炔诺孕酮的宫内节育器植入10名年龄在25至34岁之间的女性体内。在一年的随访期间，通过月经卡记录出血和点滴出血模式。在使用的第1个月，每周采集3次血样用于促黄体生成素（LH）、雌二醇（E2）、孕酮（P）和左炔诺孕酮（LNG）的放射免疫测定以及性激素结合球蛋白（SHBG）的检测；在治疗的第6个月和第12个月，每周采集2次血样。10名女性中，2名出现月经周期不规律且经期延长有点滴出血，4名在治疗后期出现闭经，另外4名月经周期正常。根据血清E2和P水平，激素谱分为四种反应类型：A）无排卵型，B）无排卵但卵泡活性高，C）有排卵但黄体功能不全，D）有排卵型。在29个治疗周期中，有10个D型、3个C型、13个B型和3个A型卵巢反应：44.8%的周期有排卵（C + D），55.2%无排卵（A + B）。一般来说，左炔诺孕酮血清水平在有排卵周期中较低，在无排卵周期中较高。差异具有统计学意义。存在明显的个体差异。血清LNG从第1个治疗月（492 pmol/l）到第6个治疗月（320 pmol/l）平均下降34.9%。闭经周期大多与有排卵型的激素谱相符，这表明闭经原因是左炔诺孕酮对子宫内膜的局部作用。左炔诺孕酮水平与血清SHBG显著相关，r = 0.8856，p < 0.001，与E2也显著相关，r = 0.4661，p < 0.05。
