Optimal embryo management strategies for patients undergoing antagonist protocols in IVF treatment.

Purpose: Selection of optimal embryo transfer strategies for IVF patients treated with antagonist protocols.

Methods: A retrospective study was conducted to assess whether whole embryo culture to the blastocyst stage could enhance the cumulative live birth rate (CLBR). The study included data from the first oocyte retrieval cycle of 4131 patients who underwent IVF treatment between January 2018 and June 2022. Patients were categorized into two strategies based on whether they underwent partial blastocyst culture (PBC) or whole embryo culture (WEC), and were further subdivided into three subgroups according to the number of high-quality embryos on Day 3: 0-2 embryos (subgroup 1), 3-7 embryos (subgroup 2), and 8 or more embryos (subgroup 3). Propensity score matching was used to perform a 1:1 match for patients across the three subgroups. The primary outcome measure was the CLBR per oocyte retrieval cycle.

Results: After propensity score matching, there were no statistically significant differences in the baseline data among patients across the three corresponding subgroups for the PBC and WEC strategies. The analysis of CLBR in single oocyte retrieval cycles revealed that subgroup 1 had a significantly higher rate with the PBC strategy compared to the WEC strategy (33.0% vs. 25.7%, P = 0.018). In subgroups 2 and 3, there were no statistically significant differences in the CLBR between patients using the two embryo management strategies.

Conclusions: When patients have 0-2 high-quality embryos on Day 3, opting for Day 3 embryo transfer rather than blastocyst culture can increase the chances of embryo transfer and improve the CLBR.