Embryo Transfer Timing for Infertility

(PRECiSE Trial)

This trial explores the optimal timing for embryo transfer during IVF (in vitro fertilization) to enhance pregnancy outcomes and patient satisfaction. It compares transferring embryos at the 8-cell stage (3 days after fertilization) with transferring them at the blastocyst stage (5-7 days after fertilization). The trial aims to guide decisions for women with 5 or fewer embryos, potentially reducing anxiety and improving treatment planning. Women undergoing their first IVF cycle with 5 or fewer embryos and not planning genetic testing may be suitable candidates for this study. As a Phase 3 trial, it represents the final step before FDA approval, offering participants the opportunity to contribute to a potentially groundbreaking treatment.

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

Research has shown that both early-stage (day 3) and later-stage (day 5) embryo transfers are generally safe. Studies indicate that transferring embryos on day 3 can lead to successful outcomes similar to those on day 5, with no major safety concerns reported for day 3 transfers.

Researchers are excited about this trial because it explores the timing of embryo transfer in treating infertility, specifically examining whether transferring embryos at the cleavage stage (day 3) or the blastocyst stage (days 5-7) leads to better outcomes. Unlike typical protocols that might not differentiate between these stages, this trial seeks to optimize the success rate by pinpointing the most effective timing for implantation. By potentially improving the chances of successful pregnancy, this research could refine and enhance current infertility treatment practices.

This trial will compare the effectiveness of two embryo transfer timings: cleavage-stage embryo transfer on Day 3 and blastocyst-stage embryo transfer on Days 5-7. Studies have shown that transferring embryos at either the early stage (Day 3) or the later stage (Days 5-7) can effectively achieve pregnancy. Research indicates that early-stage transfers can result in birth rates similar to those of later-stage transfers, especially when few embryos are available. Some studies suggest that early-stage transfers can be as effective as later-stage ones, making them a viable option for those with fewer embryos. Conversely, later-stage transfers have been linked to a higher chance of embryo implantation, potentially increasing the likelihood of pregnancy. Both methods have shown positive results, and the choice may depend on individual circumstances and preferences.¹⁵⁶⁷⁸