Vitrification with DMSO protects embryo membrane integrity better than solutions without DMSO

Area of Science:

• Reproductive Biology
• Cryobiology
• Developmental Biology

Background:

• Vitrification is a standard technique for embryo cryopreservation.
• Optimal vitrification protocols for early embryo recovery and survival are still under investigation.

Purpose of the Study:

• To compare the efficacy of two vitrification protocols with similar osmolarities for early embryo cryopreservation.
• To evaluate the impact of incubation times and cryodamage assessment methods on embryo viability.
• To assess the performance of vitrification protocols in both mouse and human embryo models.

Main Methods:

• Comparison of two vitrification protocols: Protocol A (DMSO, propane-2-diol, ethylene glycol) and Protocol B (propane-2-diol, ethylene glycol).
• Assessment of embryo viability using Alexa Fluor 488-conjugated annexin V and propidium iodide staining.
• Evaluation of embryo recovery, survival, and cleavage after vitrification and varying incubation times.
• Comparative studies using early mouse and human embryos.

Main Results:

• Both vitrification protocols demonstrated comparable embryo survival rates and were equally efficient in mouse and human models.
• Morphological assessment immediately post-vitrification was not a reliable indicator of embryo survival.
• Extended exposure to DMSO-containing solutions resulted in less cell membrane damage and death compared to DMSO-free solutions.

Conclusions:

• The choice between the two tested vitrification protocols does not significantly impact early embryo survival rates.
• Dimethyl sulphoxide (DMSO) presence in vitrification solutions appears to mitigate cryodamage.
• Accurate assessment of early embryo viability requires extended culture and evaluation of normal blastocyst development prior to clinical application.