Embryo freezing, which is usually used during In Vitro Fertilization (IVF) treatment, is a process based on freezing quality embryos that have not been used for the treatment, under controlled conditions, to be used in the future.1 Although it is commonly performed within the scope of assisted reproductive treatments, it can also be preferred to preserve future fertility.
In the first stage of IVF treatment, the ovaries are stimulated and it is aimed to collect as many eggs as possible. When the collected eggs are brought together with spermatozoa, embryos are formed if fertilization occurs. The number of quality embryos formed may vary depending on the couple. If the number of quality embryos obtained is higher than necessary, the embryo(s) that cannot be transferred to the uterus or whose transfer is delayed due to auxiliary treatments are stored by freezing, for use in the future. Different techniques can be used to freeze embryos.2
In order to preserve the viability and quality of embryos, different freezing techniques can be used: vitrification (fast freezing) and slow freezing. During the embryo freezing process, the water inside the cell is replaced with a chemical called cryoprotectant. When the vast majority of the water in the cell is replaced by cryoprotectant, the preferred freezing technique is applied.4
It is a freezing technique which consists of putting embryos into sealed tubes and then gradually lowering their temperature to -196 degrees Celsius. It reduces the risk of damage and aging of embryo cells. By its technical nature, it takes time.5 It can ensure the obtaining of embryos that do not contain ice crystals. This technique is extremely successful and the expertise, experience and technology of the center where it is performed are of critical importance.
Derived from the Latin word “vitreum”, which means glass, virtification is basically the process of turning something into a glass-like substance. Within this technique, embryos are frozen so quickly that the water in the cells does not have the time to crystallize. In this technique, in which embryos can be preserved at a high rate, also increases the likelihood that embryos will be healthy after thawing.
Frozen embryos can remain in liquid nitrogen tanks at -196°C with almost no biological process taking place. In accordance with the relevant regulations of the Ministry of Health, frozen embryos can be stored for 5 years in our country. The storage periods of embryos can be extended if necessary permissions are granted.
Healthy pregnancies can be achieved by thawing and transferring frozen embryos to the uterus as part of IVF treatment. Advances in technology can ensure the preservation of the vitality of embryos at the freezing and thawing stage. However, the rates of achieving a healthy pregnancy using frozen embryos depend on the following factors:
1 https://www.hfea.gov.uk/treatments/fertility-preservation/embryo-freezing/
2 https://www.medicalnewstoday.com/articles/314662#-how-do-people-freeze-embryos
3 https://www.hfea.gov.uk/treatments/fertility-preservation/embryo-freezing/
4 https://www.medicalnewstoday.com/articles/314662#-how-do-people-freeze-embryos
5 https://www.medicalnewstoday.com/articles/314662#-how-do-people-freeze-embryos
6 https://my.clevelandclinic.org/health/treatments/15464-embryo-freezing-cryopreservation
Not:Bu içerik genel bilgilendirme amaçlıdır, tanı ve tedavi yerine geçmez. Kişisel tanı ve tedavi planı için hekim değerlendirmesi gerekir.
