Vitrification vs Slow-Freezing: Cryopreservation Science

Both human egg and embryo cells contain significant water content. At VCRM, we utilize ultra-rapid vitrification (flash-freezing), which avoids dehydration damage and ice crystal formation entirely.

Rather than slow cooling, cells undergo brief immersion in high-concentration cryoprotectant solutions and are doused in liquid nitrogen so rapidly that water molecules solidify instantantly into a glass-like solid without forming crystalline structures.

Traditional cryopreservation techniques slowly lowered cell temperature by a few degrees per minute. Because water expands into sharp crystals when freezing slowly, traditional slow-freezing frequently damaged delicate internal egg spindles and cellular membranes, leading to low post-thaw survival rates.

Vitrification solved this obstacle, increasing egg thaw survival rates to over 90% and achieving fertilization rates equivalent to freshly retrieved eggs.

Once frozen and stored under liquid nitrogen at -196°C, all metabolic activity within eggs and embryos stops completely:

• Egg Viability: Research confirms that vitrified eggs maintain full viability without degradation for 4+ years (and ongoing studies suggest viability lasts decades).
• Embryo Viability: Vitrified embryos have been successfully thawed and transferred resulting in healthy live births after 14+ years in cryostorage (theoretically lasting indefinitely).