Transfer of thawed frozen embryo versus fresh embryo to improve the healthy baby rate in women undergoing IVF: the E-Freeze RCT.
Maheshwari A., Bari V., Bell JL., Bhattacharya S., Bhide P., Bowler U., Brison D., Child T., Chong HY., Cheong Y., Cole C., Coomarasamy A., Cutting R., Goodgame F., Hardy P., Hamoda H., Juszczak E., Khalaf Y., King A., Kurinczuk JJ., Lavery S., Lewis-Jones C., Linsell L., Macklon N., Mathur R., Murray D., Pundir J., Raine-Fenning N., Rajkohwa M., Robinson L., Scotland G., Stanbury K., Troup S.
BACKGROUND: Freezing all embryos, followed by thawing and transferring them into the uterine cavity at a later stage (freeze-all), instead of fresh-embryo transfer may lead to improved pregnancy rates and fewer complications during in vitro fertilisation and pregnancies resulting from it. OBJECTIVE: We aimed to evaluate if a policy of freeze-all results in a higher healthy baby rate than the current policy of transferring fresh embryos. DESIGN: This was a pragmatic, multicentre, two-arm, parallel-group, non-blinded, randomised controlled trial. SETTING: Eighteen in vitro fertilisation clinics across the UK participated from February 2016 to April 2019. PARTICIPANTS: Couples undergoing their first, second or third cycle of in vitro fertilisation treatment in which the female partner was aged