[Mechanism of action of intrauterine contraceptives]. / K voprosu o mekhanizme deistviia vnutrimatochnykh kontratseptivov.

PIP: 80 women underwent histological and cytological examinations. Of these, 48 had used IUDs made of polyethylene. 32 were studied before the introduction of IUDs and served as a control. Data were taken only for those women who, upon use of an IUD, suffered no menstrual disruptions, anovulatory cycles, or inflammatory complications. To study the mechanism of action of these devices, the RNA count of the endometrium was comparatively examined. In comparison with the control group, those women using IUDs showed a reduction in the endometrial RNA count in the cytoplasm of the epithelial cells at the midstage of the secretory phase of the cycle and a retardation of the secretory development of the endometrium. These changes in the functional condition of the endometrium and the absence of any ovum fecundation is considered to be due to part of the mechanism of action of the IUD.^ieng