Research Question: Are there significant differences between cumulative live birth rates (CLBR) after short or extended embryo culture when comparisons are performed per cycle?
Design: This French national study included all IVF cycles performed from January 2016 to December 2019 with at least one cleaved embryo at day 2. The day 2/3 and day 5/6 groups were identified using the National Biomedicine Agency register. Only attempts involving the vitrification method were included.