Reduction in multiple pregnancy rate in donor oocyte-recipient gestational carrier (GC) in vitro fertilization (IVF) cycles in the USA with single-embryo transfer and preimplantation genetic testing.

Purpose: To evaluate the utilization of single-embryo transfer (SET) and preimplantation genetic testing (PGT) in gestational carrier IVF cycles in the USA with donor oocyte and examine the impact on live birth and multiple gestation.

Methods: Retrospective cohort study using the Society of Assisted Reproductive Technology (SART) clinic database of 4776 donor oocyte-recipient IVF cycles in which a GC was used. The cycles were separated into 4 groups by use of PGT and number of embryos transferred as follows: (1) PGT and single-embryo transfer (PGT-SET); (2) PGT and multiple embryo transfer (PGT-MET); (3) no PGT and SET (NoPGT-SET); (4) no PGT and MET (NoPGT-MET). Primary outcomes were live birth rate (LBR) and multiple pregnancy rate (MPR).

Results: More than one blastocyst was transferred in 48.7% (2323/4774) of the cycles. When ≥1 blastocyst was transferred, with or without the use of PGT, the MPR was 45.5% and 42.0%, respectively. In comparison, in the PGT-SET and NoPGT-SET groups, the MPR was 1.4% (8/579) and 3.3% (29/883), respectively. Live birth rates increased with the use of PGT-A and with MET.

Conclusion: This study shows that SET, with or without PGT, is associated with a significantly reduced MPR in donor oocyte-recipient GC IVF cycles while maintaining high LBR. It also demonstrates that many infertility centers in the USA are not adhering to ASRM embryo transfer guidelines. Our findings highlight an opportunity to increase GC safety, which ultimately may lead to widened access to this increasingly restricted service outside the USA.