Nash H A, Robertson D N, Jackanicz T M
Contraception. 1978 Oct;18(4):395-409. doi: 10.1016/0010-7824(78)90025-2.
The correlations of plasma levels of levonorgestrel, megestrol acetate and norgestrienone with the doses delivered from subdermal implants and contraceptive rings have been examined. Differences in plasma levels as large as three-fold between different subjects receiving nearly identical doses were observed with all three steroids. The relative plasma levels seen from one subject to another showed high consistency over time. Part of the explanation may lie in differing levels of sex hormone binding globulin, but additional factors must be operative since megestrol acetate binds only weakly with this carrier.
已对左炔诺孕酮、醋酸甲地孕酮和诺孕三烯酮的血浆水平与皮下植入剂和避孕环释放剂量之间的相关性进行了研究。在接受几乎相同剂量的不同受试者之间，观察到所有三种甾体激素的血浆水平差异高达三倍。从一个受试者到另一个受试者观察到的相对血浆水平随时间显示出高度一致性。部分解释可能在于性激素结合球蛋白水平的差异，但由于醋酸甲地孕酮与这种载体的结合较弱，所以必定还有其他因素在起作用。
