What is ovarian tissue cryotransplantation?
Ovarian tissue cryopreservation and transplantation technology refers to the technology of removing part of the ovarian tissue from patients with cancer, premature ovarian failure, autoimmune or blood system diseases, and ovarian failure caused by gynecological surgery before the ovarian function declines, freezing it in vitro, and then resuming the frozen ovarian tissue and transplanting it back into the body when there is a need for fertility in the future.
Ovarian tissue cryopreservation - cryogenic freezing in a liquid nitrogen tank at -196℃
Ovarian tissue cryopreservation is suitable for the protection of fertility and ovarian endocrine function in patients with tumors and non-tumor diseases who require gonadotoxic treatment. It is the only way to protect the fertility of prepubertal girls and women of childbearing age who cannot be delayed by radiotherapy and chemotherapy. Previously, a 2-year-old girl with severe aplastic anemia had her ovarian tissue frozen before hematopoietic stem cell transplantation. The medical team separated the ovarian tissue, further processed the ovarian cortex, and preserved it in a liquid nitrogen tank at -196℃ using vitrification technology. In a deep cryogenic state, intracellular metabolic activity has stopped, and the follicles in the ovarian tissue can survive for a long time and preserve the original genetic material. The success of this case has set a precedent for the preservation of prepubertal fertility in my country, retaining "vitality" for patients and bringing hope.
For prepubertal girls, ovarian tissue cryopreservation is the only method of fertility preservation. Ovarian tissue is frozen before puberty and transplanted after puberty. More than 10 live births have been achieved worldwide using this method. During this period, the interval between freezing and transplantation is long, so the environmental requirements for ovarian tissue freezing are extremely strict. It must not only be safe and stable, but also ensure that cell activity is not lost. Cryopreservation of ovarian tissue in a liquid nitrogen tank at minus 196°C is the main storage method at present, and it is also the safest and most effective method.
Advantages of ovarian tissue cryopreservation
After freezing embryos and eggs, ovarian tissue cryopreservation has become a new option for preserving fertility. However, there are still many restrictions on the technology of freezing embryos and eggs. In my country, according to relevant laws and regulations, it is prohibited for single women to freeze eggs, and freezing embryos requires married women. For ovarian cryopreservation, the scope of application can be expanded to pre-puberty and there are no special regulations for the patient's marital status. In addition, by freezing ovarian tissue to preserve fertility, waiting for the disease to be cured, thawing the ovarian tissue and transplanting it back into the body, it can not only provide patients with the opportunity to regain fertility, but more importantly, the ovaries can restore endocrine function, regulate estrogen levels, and keep women young and energetic.