Over the years, there have been various different methods such as freezing eggs or embryos, for preserving a woman’s fertility, but a relatively newer technique that has been developed is ovarian tissue banking or ovarian tissue cryopreservation. An experimental approach, the primary purpose of this technique was the preservation of the fertility of young women who were undergoing chemotherapy for cancer. The women’s ovaries as well their chances of undergoing a healthy pregnancy are destroyed due to these treatments involving radiation, which is why they can opt for this procedure where their ovaries are removed. The ovarian tissue is then dissected and frozen.
Patients who are about to undergo chemotherapy and radiation therapy, or a stem cell or bone marrow transplantation can be great candidates for ovarian tissue banking. Women who are of pre-pubertal age cannot undergo ovarian stimulation and retrieval of the egg, can also undergo ovarian tissue banking. Women who are pre-menopausal and don’t have enough time for embryo or egg freezing.
This is also a great option for women who want their own children but do not want to get married or start until later, and they may be concerned about having fertility issues at that time. With age, a woman’s eggs start degenerating or become less fertile. Thus women at the age of 35 who are not married but want to have children may be worried about what to do. Here is where ovarian tissue freezing comes into play. It is a new technique but it can give a woman the chance of becoming a mother, despite these issues.
In the procedure, a part of the ovaries or the whole ovary is removed surgically, usually by performing a laparoscopy. Then, the stromal layer of the ovary is removed and the cortical part is left for freezing. After this, the ovarian cortex, the outer layer of the ovary is cut into small, thin strips and kept in a medium that contains a cryo-protectant. It is then kept in plastic vials which are kept into a machine that will freeze the vials to -196°C. After this, the vials are stored in liquid nitrogen. These strips of the ovarian tissue contain primordial follicles, each of them holding a single immature egg. A small amount of tissue is kept aside for confirming that the primordial follicles are present.
When the patient has undergone chemotherapy or other treatments and is ready for pregnancy, the tissue can then be thawed. It is then transplanted back into the body, either on the remaining ovary or anywhere else. It depends on where the transplantation is done. If the tissue is transplanted into the pelvis, pregnancy may be spontaneous whereas if placed outside the pelvis, hormone treatment would be required for stimulating the ovaries and in vitro fertilisation would be performed for fertilising the egg, creating an embryo and transferring it into the uterus.
Ovarian tissue banking can be performed at a very short notice, whereas embryo and egg freezing may take longer to complete. It is an excellent method for girls who are very young.
There may be a few risks associated with ovarian tissue banking, such as the risk of complications from anaesthesia. While removing the tissue, the remaining part could get damaged or the immature follicles may get damaged while they’re being frozen or stored. Although, the chances of such a thing happening are rare.
This is still an experimental approach so you should be completely thorough about the whole procedure and consult your doctor before deciding to undergo ovarian tissue banking.