Treatments

Description of available treatments

IVF/ICSI treatments

Vitrification

Vitrification is the process whereby the solution containing the oocytes/embryos is cooled so quickly that the structure of the water molecules doesn’t have time to form ice crystals and instantaneously solidifies into a glass-like structure. This is important since formation of ice crystals can damage the oocytes/embryos. Rates of 90-95% survival have been published in many scientific journals.

Physiologically, oocytes/embryos are large cells, and their outer layer is fairly water-resistant. When water is cooled to below its freezing point, it solidifies in a crystalline structure known as ice. Because ice is less dense than liquid water, it necessarily follows that ice crystals occupy a greater volume than does the liquid water from which they were formed. As adjacent volumes of liquid water within a cell solidify, their expansion into ice causes pressure and shearing forces on intracellular organelles, which can suffer considerable damage. Avoidance of ice-crystal formation therefore is one of the principal goals of successful cryopreservation. When water is trapped inside an oocyte or the embryo blastomeres, ice crystals formed during the cooling process can damage the oocyte. However, the technique of vitrification prevents the formation of ice crystals by adding highly concentrated cryoprotectant solutions and cooling the cells at an extremely rapid rate. To reduce exposure to the toxic cocktail of cryoprotectants and prevent extreme dehydration, cells are exposed to the cryoprotectant solutions for a very short period. Therefore, the procedure is faster, with higher expected yields. It has been suggested that vitrification may be less traumatic to the meiotic spindle (it is a detrimental apparatus within each cell of our body and its function is to help the cells divide normally) and may also have less effect on cell physiology.