Reproductive Outcomes of Transferring Blastocysts Derived From Frozen-Thawed Cleavage Embryos: A Systematic Review...

In in vitro fertilization (IVF), transferring frozen-thawed blastocysts is a widely adopted practice. This meta-analysis aims to evaluate the reproductive outcomes of transferring blastocysts derived from frozen-thawed cleavage embryos (FT-CDB group) compared to direct frozen-thawed blastocyst (DFB group) transfers.

We searched the following electronic databases for relevant studies: PubMed/MEDLINE, EMBASE, Scopus, and Web of Science. Studies were included if they compared the clinical and neonatal outcomes of IVF patients receiving either FT-CDB or DFB transfer with vitrification method. The protocol for this review has been registered in PROSPERO.

A total of seven studies (2057 patients) were included in the analysis. Participants in the FT-CDB group demonstrated significantly higher odds of achieving clinical pregnancy (OR 1.24, 95% CI 1.03-1.49, p = 0.022, I ² = 27%), and live birth (OR 1.31, 95% CI 1.08-1.60, p = 0.007, I ² = 0%) compared to the DFB group. No significant differences were observed in the birth weights of infants between the groups (MD -87.05 g, 95% CI -293.77 to 119.67, p = 0.41, I ² = 83%).

Transferring blastocysts derived from frozen-thawed cleavage embryos is associated with higher odds of clinical pregnancy and live birth compared to frozen-thawed blastocyst transfers.

PROSPERO number: CRD42024591620.