Transfer and uterine factors are the major recipient-related determinants of success with donor eggs

OBJECTIVE: To define the recipient-related determinants of outcome with donor eggs. DESIGN: Case-control study. SETTING: Community hospital-based assisted reproductive technology (ART) program. PATIENT(S): One hundred thirty-four embryo transfers (ETs) in which two recipients were matched to one donor. INTERVENTION(S): Controlled ovarian hyperstimulation (COH) and ovum retrieval in donors; IVF and ET to recipients. MAIN OUTCOME MEASURE(S): Recipients' age, body mass index (BMI), medical conditions, endometriosis, gravidity, uterine pathology, endometrial thickness, egg number, total motile sperm count, intracytoplasmic sperm injection (ICSI), zygote number, fertilization rate, embryos per ET, embryos frozen, embryo quality, difficulty with transfer, and ongoing pregnancies per ET. RESULT(S): Forty-one recipient pairs had discordant outcomes. Pregnant patients had a lower frequency (9.7% vs. 31.7%, P=.04) and lesser severity of uterine pathology. Endometrium <8 mm was found solely in failed cycles. Pregnant women had fewer moderate or difficult ETs (9.7% vs. 31.7%, P=.04) and more good embryos (1.8 vs. 1.3, P=.03) than the nonpregnant group. CONCLUSION(S): Analysis of recipient pairs with discordant outcomes identifies the recipient-related predictors of success by keeping oocyte quality and the laboratory component constant. Uterine pathology, thin endometrium, transfer difficulty, and number of high-grade embryos are the principal recipient-related determinants of outcome with donor eggs.