HAEMOSTASIS IN MENSTRUAL ENDOMETRIUM IN THE PRESENCE OF AN INTRAUTERINE DEVICE

Abstract

The histology and ultrastructure of the hemostatic response in the [human] endometrium was studied in 12 uteri containing an inert or Cu wound intrauterine contraceptive device (IUD). The uteri were removed during the premenstrual phase or during the first 96 h of menstruation. The results were compared to earlier observations in non-IUD influenced endometrium. In all uteri the tissue shedding proceeded more slowly in the presence of an IUD and considerably fewer hemostatic plugs were found. The platelets in these plugs were more loosely packed and less degranulated, and the plugs contained less fibrin than in the absence of an IUD. Hemostatic plugs were still observed at times when no such plugs were seen in uteri without an IUD. Unoccluded vessel lesions were regularly seen and vessels open to the shedding surface were occasionally encountered. Apparently, IUD-induced menorrhagia is caused by the combination of delayed shedding and a decreased hemostatic reaction in the endometrium.