Cryopreservation is a group of processes that include the preparation, freezing, and storage of human gametes, pre-implantation embryos, and tissues at ultra-low temperatures, most often in liquid nitrogen. It plays an important role in assisted reproduction, as it enables the reproductive cells collected and/or fertilized in a single treatment cycle to be used for fertilization and/or implantation in the patient's uterus, in a future treatment cycle. This increases the effectiveness of infertility treatment and reduces costs and discomfort for patients.
In 2008, SALAGRM “Sofia” introduced vitrification as the main method of freezing gametes and embryos. It is a superfast freezing technique that results in the formation of a vitreous state in living cells. This method has been shown to avoid the formation of ice crystals in the structure of reproductive cells and embryos during freezing and thawing. 90% cell survival rate can be achieved if freezing sperm cells, oocytes, and embryos through vitrification.