ABSTRACT
The serum concentration of estradiol, progesterone [prog], levonorgestrel [LNG] and sex hormone binding globulin [SHPG] were measured and endometrial specimens were histologically examined in 50 women who had been using the contraceptive implants NORPLANTR for about five years. The hormonal levels obtained in different phases of the menstrual cycle suggested the occurrence of cyclic ovarian hormone production. However, prog. Concentration did not attain levels suggestive of normal corpus luteum function. The mean serum concentration of LNG was 0.3 +/- 0.15 [SD] ng/ml, a level similar to those reported for the earlier phases of NORPLANTR use. SHBG concentration was on the average 13.61 9.9 nmoL/L, lower than the mean value reported for normal women not using hormonal contraception. Again, endometerial patterns were suggestive of ovarian cyclisty. However, suppressed endo-metrium was found in 10, and irregular secretory pattern in 11 out of the 43 readable biopsies. Foci of cystic glandular hyperplasia were found in four specimens that showed otherwise proliferative endometrium.No evidence of malignant transformation were found in either the glandular or stromal elements. The results indicate that prolonged use of NORPLANT[R] does not result in a state of chronic hypoestrenism