Endometriosis is not detrimental to embryo implantation in oocyte recipients

Purpose: Our purpose was to determine the effects of endometriosis on implantation and pregnancy rates in ovum recipients. Methods: The medical records of 239 consecutive oocyte recipient patients who were treated between January 1, 1991, and June 30, 1995, were analyzed retrospectively Recipients with endometriosis (group I; n = 55) were compared to recipients without endometriosis (group II; n = 184). Patients in group I had active endometriotic disease confirmed by laparoscopy and were subdivided into mild (Stages I and II; n = 18) and moderate to severe (Stages III and IV; n = 37) endometriosis. Results: No difference was found in recipient age, endometrial thickness, donor age, and embryos transferred. The pregnancy rates (28 versus 29%) and implantation rates (12 and 13%) were also comparable between group I and group II, as well as between patients with mild and patients with moderate to severe endometriosis. Conclusions: The presence of endometriosis in oocyte recipients does not lower implantation or pregnancy rates. We conclude that the adverse effect of endometriosis on reproductive outcome is not related to implantation but, in fact, is most likely an effect on oocyte or embryo quality.