Embryo cryopreservation provides many conveniences for couples undergoing IVF treatment. After embryo transfer, the remaining embryos are monitored by embryologists. If they are suitable for freezing, with the couple’s written consent, they are frozen and stored in liquid nitrogen at -196°C. When the frozen embryos need to be thawed, they are removed from liquid nitrogen and thawed at room temperature. They are then separated from the protective solution and placed in a special culture medium. They are placed in an incubator (devices where embryos are kept).
Embryo cryopreservation offers cost advantages in cases where IVF treatment fails to achieve pregnancy, results in a miscarriage, or when there is a desire for a second child after a successful pregnancy. By thawing and transferring the frozen embryos belonging to the couple, the need for prolonged hormone medication for the woman is eliminated. Additionally, since all the necessary stages of the IVF procedure are bypassed, it provides a cost-effective convenience.
Furthermore, if any issues arise for the woman at the time when the embryos are scheduled for transfer, all the embryos can be frozen. This eliminates the risks that endanger the patient’s life (OHSS) and reduces the chances of pregnancy due to excessive hormone secretion. Similarly, if the endometrium lining is not suitable for pregnancy due to inadequate thickness, the embryos can be frozen and stored. They can then be transferred at a later time when the uterus is better prepared. Alternatively, all obtained embryos can be cryopreserved for any social reasons.
It has been reported that pregnancy rates obtained after frozen embryo transfers in reputable centers worldwide are higher than the pregnancy rates from fresh treatments. The main reason for this is the proper and precise use of embryo cryopreservation techniques, which result in the preservation of embryo viability after thawing, allowing for a more natural uterine environment and ultimately achieving better pregnancy rates.