长期使用Norplant皮下埋植剂妇女血清左炔诺孕酮水平的测定

Serum Levels of Levonorgestrel during Longterm Use of Norplant

目的（１）测定使用Ｎｏｒｐｌａｎｔ皮下埋植剂（１～１１年）的妇女血清左炔诺孕酮（ｌｅｖｏｎｏｒｇｅｓｔｒｅｌ，ＬＮＧ）水平，预测其可能使用的最长有效期限；（２）观察长期（５年）用药后血清ＬＮＧ水平与受试者体重间的相关性。方法应用放射免疫法测定血清中ＬＮＧ水平。结果使用Ｎｏｒｐｌａｎｔ１、３、５年后，血清ＬＮＧ均值分别为１２７３．５ｐｍｏｌ／Ｌ、９２４．０ｐｍｏｌ／Ｌ和７３９．６ｐｍｏｌ／Ｌ。第５～７年血清ＬＮＧ均值呈线性降低，第７～１０年，血清ＬＮＧ均值变化不明显。通过观察使用Ｎｏｒｐｌａｎｔ满５年的妇女发现，血清ＬＮＧ水平与体重呈负相关。结论体重小于６０ｋｇ的妇女。

Objective (1) Assessment of longest effective contraceptive duration of Norplant (containing levonorgestrel, LNG) by serum levonorgestrel levels. (2) To observe the possible relationships between the serum LNG levels of longterm use (5 years) and body weight. Methods To determine serum LNG levels in 230 women among 1 356 cases at various intervals between 1 and 11 years after implantation using RIA kits provided by WHO. Results The average serum levels of LNG in users of Norplant at the 1st, 3rd, 5th years were 1 273.5, 924.0 and 739.6pmol/L respectively. From the 5th to 7th years average serum LNG levels showed almost a linear decline, and from the 7th through 10th year it did not show much changes. The average serum LNG level was (511.1209) pmol/L. A significant negative correlation was found between serum LNG levels and body weight at the 5th years. ConclusionT5BZOne set of Norplant implants may provide effective contraception for 810 years in women with body weights less than 60kg.