Abstract

PIP: Protein and nucleic acid concentrations and activities of acid and alkaline phosphatase, beta-glucuronidase, and lactic dehydrogenase were systematically studied in endometrial biopsy specimens obtained from 10 24-35 year old women in this investigation. The biopses were taken during the proliterative phase on Cycle Days 10, 11, or 12 and during the luteal phase on Cycle Days 20, 21, 22, and 23 during the 2 consecutive cycles prior to insertion of the Cu-T, during several cycles of year 1 following insertion, and during the first 2 cycles after removal of the device. A significant increase in endometrial protein concentration occurred during Cycle 11-12 with the device in situ. No change was found in DNA or RNA concentrations. A significant decrease in alkaline phosphatase activity occurred in the secretory phase during and following Cycle 6 with the Cu-T in situ. The acid phosphatase activity was significantly increased in the proliferative phase during and following Cycle 6 with the device in utero. A significant decrease in beta-glucuronidase activity occurred with the Cu-T in situ, but no significant change in lactic dehydrogenase activity occurred. Since the enzymes examined are involved with the implantation of the ovum, their alterations may be the mode of action of the Cu-T.