OBJECTIVE: To evaluate the benefit of next-generation sequencing (NGS)-based preimplantation genetic testing for aneuploidy (PGT-A) for embryo selection in frozen-thawed embryo transfer. DESIGN: Randomized controlled trial. SETTING: Not applicable. PATIENT(S): Women aged 25-40 years undergoing IVF with at least two blastocysts that could be biopsied. INTERVENTION(S): Randomization for single frozen-thawed embryo transfer with embryo selection based on PGT-A euploid status versus morphology. MAIN OUTCOME MEASURE(S): Ongoing pregnancy rate (OPR) at 20 weeks' gestation per embryo transfer. RESULT(S): A total of 661 women (average age 33.7 ± 3.6 years) were randomized to PGT-A (n = 330) or morphology alone (n = 331). The OPR was equivalent between the two arms, with no significant difference per embryo transfer (50% [137/274] vs. 46% [143/313]) or per intention to treat (ITT) at randomization (41.8% [138/330] vs. 43.5% [144/331]). Post hoc analysis of women aged 35-40 years showed a significant increase in OPR per embryo transfer (51% [62/122] vs. 37% [54/145]) but not per ITT. CONCLUSION(S): PGT-A did not improve overall pregnancy outcomes in all women, as analyzed per embryo transfer or per ITT. There was a significant increase in OPR per embryo transfer with the use of PGT-A in the subgroup of women aged 35-40 years who had two or more embryos that could be biopsied, but this was not significant when analyzed by ITT. CLINICAL TRIAL REGISTRATION NUMBER: NCT02268786.
IVF, frozen-thawed embryo transfer, next-generation sequencing, preimplantation genetic testing, single-embryo transfer