The effect of intrauterine devices, the stainless steel ring, the copper T220, and releasing levonorgestrel, on the bleeding profile and the morphological structure of the human endometrium--a comparative study of three IUDs. A morphometric study of 96 cases.

Thirty-four women using the stainless steel ring (SS), 43 women using the Copper T220 (TCu), and 19 women using levonorgestrel-releasing intrauterine devices (LNG) were admitted to the study. The light microscopic biopsy material was subjected to morphometric studies including 8 indices of endometrial activity before (Control) and after 24 months of exposure to the SS and TCu device and 3-10 months of exposure to the LNG device. The women were grouped into subjects with and without intermenstrual and prolonged bleeding. The results revealed that there were highly significant differences between the IUDs at the endometrial level as displayed by morphometry. However, the difference between bleeders and non-bleeders was not significant in any of the three types of IUDs. Although the mode of action of these IUDs at the endometrial level is different, the mechanism responsible for the irregular endometrial bleeding needs to be further investigated.