Application of a single "Universal warming protocol" for vitrified donor oocytes: A multicenter study

Area of Science:

• Reproductive Medicine
• Cryobiology
• Oocyte Vitrification

Background:

• Donor oocyte cryopreservation is crucial for assisted reproductive technologies.
• Vitrification and subsequent warming (devitrification) protocols aim to maximize oocyte survival and viability.
• Optimizing devitrification media is essential for successful cryopreservation outcomes.

Purpose of the Study:

• To evaluate the efficacy of the Universal Warming Protocol (UWP) for donor oocyte devitrification.
• To compare the outcomes of using different devitrification media with oocytes vitrified using a single medium.
• To determine if devitrification media must match the vitrification medium.

Main Methods:

• A multicenter study involving 2172 donor oocytes (metaphase II) vitrified using Kitazato media.
• Oocytes were devitrified using three different media: Kitazato, Irvine, and RapidWarm Omni.
• Key parameters assessed included survival, fertilization, cleavage, blastulation, and pregnancy rates (biochemical and clinical).

Main Results:

• The RapidWarm Omni media resulted in a statistically higher oocyte survival rate (94%) compared to Kitazato (86%) and Irvine (85%) media (P < 0.01).
• No significant differences were observed in fertilization, cleavage, or blastulation rates across the groups.
• Clinical pregnancy rates were comparable or higher when using Irvine and RapidWarm Omni media for devitrification.

Conclusions:

• The assumption that oocyte devitrification media must match the vitrification medium is not supported.
• It is feasible to use different devitrification media for donor oocytes previously vitrified with the same medium.
• This flexibility can enhance the efficiency and success of donor oocyte cryopreservation programs.