Comparison of perinatal outcomes following frozen embryo transfer cycles using autologous versus donor oocytes in women 40 to 43 years old: analysis of SART CORS data.

OBJECTIVE: To study the differences in perinatal outcomes after frozen embryo transfer cycles using autologous or donor oocytes in women of advanced maternal age. DESIGN: Historical cohort study. SETTING: US national database from the Society of Assisted Reproductive Technology Clinic Outcome Reporting System (SART CORS) from 2009 to 2013. PATIENT(S): Women at 40-43 years of age undergoing autologous frozen embryo transfers (a-FET) or donor oocyte frozen embryo transfers (d-FET) resulting in singleton pregnancies that were entered in the SART CORS database from 2009 to 2013. RESULTS: a-FET resulted in 4402 singleton live births whereas d-FET resulted in 2703 singleton live births. d-FET resulted in a higher risk of preterm births (< 37 weeks), with adjusted odds ratio (aOR) 1.33 (95% CI 1.02-1.75), but similar risk of small for gestational age (SGA), with aOR 1.75 (95% CI 0.85-3.7), when compared to a-FET. However, when only single blastocyst transfer cycles are considered, d-FET and a-FET showed no difference in preterm births or other adverse perinatal outcomes. CONCLUSIONS: Singletons resulting from d-FET are at increased risk for perinatal morbidity. However, the risk was diminished in single blastocyst transfer cycles. Our study supports the current American Society for Reproductive Medicine (ASRM) guidelines of transferring a single blastocyst in d-FET cycles.