Early chorionic activity in women bearing inert IUD, copper IUD and levonorgestrel-releasing IUD.

ABSTRACT

PIP: Early chorionic activity was compared in 100 IUD users (inert device, copper IUD, and a levonorgestrel-releasing IUD) and 22 controls through measurement of the serum human chorionic gonadotropin (hCG) beta-fraction. In the control group, 7 (32%) of the 22 women had hCG beta-fraction values indicative of chorionic activity (i.e., 5mIU/ml). In the group of women wearing an inert IUD (Lippes Loop), 8 (20%) were positive for early chorionic activity. In contrast, the incidence of premenstrual chorionic activity signs was very low among women with medicated IUDs: 5% among acceptors of the copper IUD and zero among women in the levonorgestrel-releasing IUD group. In general, elevated premenstrual hCG values are indicative of failed implantation. The high incidence of hCG activity recorded among Lippes Loop acceptors in this study is consistent with the anti-implantation effect postulated for inert devices. In contrast, medicated IUDs appear to act by preventing rather than interrupting implantation and therefore should not be regarded as abortifacient contraceptive agents.