Embryo cryopreservation and vitrification

Embryo cryopreservation using vitrification

If a larger number of high-quality embryos at the blastocyst stage are created during an IVF treatment cycle, they can be safely stored for future use through cryopreservation, which takes place on the 5th or 6th day of culture. In our centre, we use the most advanced method – vitrification, which enables ultra-rapid freezing of embryos without the formation of ice crystals that could damage the embryo cells. This helps preserve the structure and viability of the embryos as much as possible.

The embryos are then stored in a cryobank in liquid nitrogen at a temperature of −196 °C. Under these conditions, they can be safely stored for a very long time, even for several decades, without any deterioration in their quality.

Main benefits

The greatest benefit of cryopreservation is the possibility of repeated embryo transfer without the need for new ovarian hormonal stimulation and egg retrieval. This means not only a gentler course of treatment, but also a lower physical and psychological burden for the patient and, usually, a reduction in overall costs.

Another benefit is the possibility of flexible transfer planning at the optimal time, when the uterine lining is best prepared to receive the embryo.

Frozen embryo transfer

Frozen embryos can be gently thawed at any time and transferred into the uterus as part of a process called frozen embryo transfer (FET). Thanks to modern methods, the success rate of this procedure is comparable to the transfer of fresh embryos.

Other possible uses

Cryopreservation methods can also be used to freeze reproductive cells – eggs and sperm. Cryopreservation therefore represents a comprehensive solution for preserving fertility, for example before planned oncological treatment or for personal reasons, known as social freezing.