Embryo Biopsy and Perinatal Outcomes for Singletons: An analysis of 16,246 frozen embryo transfer cycles reported in SART CORS.

Abstract Background Preimplantation genetic testing (PGT) is commonly performed by removal of cells from the trophectoderm, the outer layer of the blastocyst which will give rise to the placenta. Because PGT removes cells that are destined to form the placenta, it is possible that PGT could be associated with increased risk of adverse outcomes associated with abnormal placentation. Despite the increasing utilization of PGT, few studies have investigated perinatal outcomes, with published studies yielding contradictory findings, and of limited sample size. Objective(s) To compare perinatal outcomes for singleton pregnancies conceived following frozen embryo transfer of a single autologous blastocyst transfer, with and without PGT. Study Design Retrospective analysis of autologous frozen embryo transfer cycles leading to singleton live birth from the Society for Assisted Reproductive Technology Clinical Outcomes Reporting System (SART CORS), including cycles initiated from 2014-2015. Perinatal outcomes including birth weight, Z-score, small for gestational age, large for gestational age, macrosomia, and preterm birth were compared between pregnancies with and without PGT. We conducted multivariable linear regression for birth weight and Z-score and logistic regression for binary outcomes. False discovery rate was adjusted to decrease the Type I error from multiple hypothesis testing. Results Of 16246 frozen embryo transfers resulting in singleton birth included in this analysis, 6244 involved transfer of a single blastocyst which had undergone PGT, and the remainder (n=10,002) involved transfer of a single blastocyst which had not undergone biopsy. Compared to women from non-PGT group, average maternal age (35.8 ± 4.1 vs. 33.7 ± 3.9, p Conclusion Compared to FET without PGT, FET cycles with PGT was associated with a small increase in the likelihood of preterm birth. Although the increase in risk for prematurity was modest in magnitude, further investigation is warranted.