Premature onset of menstrual bleeding during ovulatory cycles in women with an intrauterine contraceptive device

Abstract

Daily peripheral plasma levels of progesterone and estradiol were determined during 13 menstrual cycles in 10 women with an intrauterine contraceptive Copper-T device (model TCu 200) and during two menstrual cycles in two women with a Lippes loop. As judged from the hormonal levels all cycles were ovulatory. Normal patterns of progesterone and estradiol were found as compared to 34 ovulatory control cycles for progesterone and 10 ovulatory control cycles for estradiol. However, in relation to the hormonal patterns, the menstrual bleeding usually started about two days earlier in the Copper-T cycles than in the control cycles, e.g., two days before progesterone and estradiol levels had declined to levels normally found at the onset of a menstrual bleeding. Similar findings were made in the two cycles from the women with a Lippes loop. The premature shedding of the endometrium in women with IUCD's may be due to endometrial changes caused by the device.