Detrimental effect of endometrial biopsies on pregnancy rate following human menopausal gonadotropin/human chorionic gonadotropin-induced ovulation.

The effect of luteal phase endometrial biopsy was studied in 33 anovulatory women treated with human menopausal gonadotropins (hMG) to induce ovulation and pregnancy. Over-all, 33 of 85 ovulatory cycles resulted in pregnancy (39%). Of 50 nonbiopsied cycles, 26 resulted in pregnancy (52%) whereas only 7 of 35 biopsied cycles resulted in pregnancy (20() (P less than 0.01). Four pregnancies terminated in spontaneous first-trimester abortions, 12% in the nonbiopsied group and 14% in the biopsied group. Luteal phase endometrial biopsy significantly lowers pregnancy rates in hMG-induced ovulatory cycles, but does not change abortion rates.