Improved clinical outcomes with a modified warming protocol in donor oocyte cycles

Area of Science:

• Reproductive Medicine
• Embryology
• Cryopreservation

Background:

• Optimizing laboratory efficiency in assisted reproductive technologies is crucial.
• Shortening warming times for cryopreserved embryos is explored, but oocyte warming protocols require further evaluation.
• This study assesses a modified warming protocol (MWP) for vitrified donor oocytes.

Purpose of the Study:

• To evaluate the impact of a modified warming protocol (MWP) on embryonic development.
• To assess pregnancy outcomes following the use of vitrified donor oocytes warmed with MWP.
• To compare MWP with conventional warming protocol (CWP) and fresh oocytes.

Main Methods:

• Retrospective cohort study of 13,103 donor oocytes from January 2019 to August 2024.
• Oocytes were divided into three groups: conventional warming protocol (CWP), modified warming protocol (MWP), and fresh.
• Data analyzed included oocyte survival, fertilization rates, blastocyst formation, and ongoing pregnancy/live birth rates.

Main Results:

• Survival rates were similar between CWP and MWP groups (93.7% vs. 93.9%).
• Blastocyst formation (77.3%) and usable blastocyst formation (51.4%) were significantly higher with MWP compared to CWP (57.5% and 35.4%).
• Ongoing pregnancy/live birth rates were higher with MWP (66.7%) than CWP (50.4%), with MWP showing a positive association with outcomes.

Conclusions:

• The modified warming protocol (MWP) enhances blastocyst formation and pregnancy outcomes for vitrified donor oocytes.
• MWP results are comparable to those of fresh oocytes.
• MWP is proposed as a potential replacement for CWP to optimize donor cycle outcomes.