Impact of embryo biopsy for pgt-m testing on pregnancy outcomes

Preimplantation genetic testing for monogenic disease (PGT-M) is indicated for patients who are known carriers of or affected by single gene disorders There are limited data on neonatal outcomes from PGT-M transfers. Our objective is to compare neonatal outcomes in pregnancies resulting from embryos with PGT-M testing compared those that did not undergo biopsy. etrospective Cohort Study using Society of Assisted Reproductive Technologies- Clinical Outcomes Reporting System (SART-CORS) data. Frozen embryo transfer (FET) cycles of autologous blastocysts with and without biopsy for PGT-M were included. Primary outcomes included percentage large for gestational age (LGA), small for gestational age (SGA), and preterm delivery (PTD). Secondary outcomes included high birthweight (HB), term low birthweight (LBW) and clinical pregnancy measures. Sensitivity analyses were performed on cycles restricted to elective single embryo transfer (eSET) and singleton pregnancies. 628 PGT-M FET cycles and 9,046 non-PGT-M cycles were included. Patients undergoing PGT-M testing were younger (33±3.8 vs. 36±4.1 p<0.001) and were less likely to have a infertility. After adjusting for known confounding variables including age, race, BMI, smoking status, number of prior IVF cycles, previous births, and infertility diagnosis, the embryos that underwent PGT-M testing resulted in similar LB and did not exhibit differences in LGA, SGA or PTD. Transfers of PGT-M tested embryos were associated with lower miscarriage rate, aRR 0.69 (CI 0.48-0.98; p<0.001). In the sensitivity analyses, PGT-M FET cycles were associated with a higher likelihood of term LBW and SGA in eSET cycles. There was no difference in PTD. Similar results were observed in cycles with singleton pregnancies. PGT-M testing was associated with an increase in term LBW and SGA in blastocyst FET cycles in analyses restricted to eSET cycles and singleton pregnancies. While the analysis controlled for multiple confounding variables, there are other possible variables that may confound this association, including the day of biopsy which was not available in the SART database.