A 10%-15% reduction in live birth rate and a 47% decrement in multiple birth rate with single embryo transfer (SET) compared with double embryo transfer (DET) was observed in the setting of favorable patient prognostic factors, a recent study found. This retrospective cohort analyzed factors associated with high live birth rate and low multiple birth rate in fresh and frozen-thawed assisted reproductive technology (ART) cycles between 2004 and 2013. The study population included 181,523 women undergoing in vitro fertilization (IVF) with autologous fresh first cycles, 27,033 with fresh first oocyte donor cycles, 37,658 with fresh second cycles, and 35,446 with frozen-thawed second cycles. Researchers found:
- In patients with favorable prognostic factors, including younger maternal age, transfer of a blastocyst, and additional embryos cryopreserved, the gain in the live birth rate from SET to DET was ~10% to 15%.
- However, the multiple birth rate increased from ~2% to >49% in both autologous and donor fresh and frozen-thawed transfer cycles.
Mersereau J, Stanhiser J, Coddington C, Jones T, Luke B, Brown MB. Patient and cycle characteristics predicting high pregnancy rates with single embryo transfer: An analysis of the Society for Assisted Reproductive Technology outcomes between 2004 and 2013. [Published online ahead of print September 16, 2017]. Fertil Steril. doi:10.1016/j.fertnstert.2017.07.1167.