ASRM Guidelines for the number of fresh embryos to transfer were developed initially in 2008 and then updated in 2013. The guidelines were developed to address the increasing number of twins and high order multiples that IVF programs were reporting to SART. They recommended that patients <35 years old have elective single embryo transfer (eSET) unless they had two or more previously failed IVF cycles, poor embryo quality, or a low chance of having embryos cryopreserved. These guidelines apply to fresh embryo transfers.
We have observed an increase in twins in our frozen embryo transfer (FET) patients as cryopreservation methods have improved. Therefore, we sought to compare the live birth rates and multiple pregnancy rates for patients having eSET vs. elective double embryo transfer (eDET) in FET cycles. 391 patients, who met the criteria for eSET (< 35 years old; >1 cryopreserved blastocyst available), self-elected to have either eSET or eDET in their FET cycle.
We found no statistically significant differences in live birth rates between eSET and eDET cycles, but a significant decrease in multiple pregnancy rates with eSET. We conclude that eSET in FET cycles will reserve cryopreserved embryos for future FET attempts while decreasing multiple pregnancy complications and fetal loss and represents a significant potential cost savings for delivery and management of newborns born through IVF technologies.
Melanie R. Freeman, PhD1, M. Shaun Hinds, BS1, C. Kay Howard, BS1, Julie Howard, BS1, and George A. Hill, MD2. 1Ovation Fertility, Nashville, TN; 2Nashville Fertility Center, Nashville, TN