Blastocyst versus cleavage embryo transfer improves cumulative live birth rates, time and cost in oocyte recipients:
Elisabet Clua1, Ignacio Rodríguez1, Gemma Arroyo1
1Department of Obstetrics Gynecology and Reproductive Medicine, Dexeus University Hospital, Gran Via de Carles III, 71 08028 Barcelona, Spain.
Research Question:
Does embryo transfer day (day 5 versus day 3) affect cumulative live birth rates (CLBR), time to live birth (TLB) and cost per live birth (CPL) in recipients of donated oocytes?
Study Design:
A single-centre RCT conducted between April 2017 and August 2018. Recipients of donated oocytes were randomized to cleavage-stage (day 3) or to blastocyst-stage (day 5) embryo transfer. Eligible recipients were aged 18-50 years and in their first or second synchronous cycle. Primary outcome was CLBR (12 months from first embryo transfer), and fresh and subsequent cryopreserved transfers were considered; TLB and CPL were also analysed.
Results:
Recipients (n = 134) were randomized to the day-3 group (n = 69) or to the day-5 group (n = 65). Day-5 transfer resulted in a 15.9% relative increase in CLBR and a significant shorter TLB compared with day-3 transfer. To reach a 50% CLBR, the day-3 group required 6 months more than the day-5 group (15.3 versus 8.9 months, respectively). The average CPL in the day-3 strategy cost 24% more than the day-5 strategy (€14817.10 versus €10959.20). Clinical pregnancy rate was 25% less in the day-3 group. The trial was prematurely stopped after poor initial results in the day-3 arm led to unplanned interim analysis.
Conclusions:
The transfer of blastocyst-stage embryos in recipients of donated oocytes is preferred as it leads to a higher clinical pregnancy rate, live birth rate, shorter time to pregnancy and lower costs to achieve live birth, compared with cleavage-stage embryo transfer.
