By retrieving and cryopreserving ovarian tissue prior to initiation of the cancer treatment, there is now a possible option of restoring fertility by implanting the cryopreserved-thawed ovarian tissue after recovery.
Our laboratory has performed ovarian tissue cryopreservation since 1999, and has one of the most well-established protocols for the procedure in the world.
Cryopreservation of ovarian tissue for fertility preservation
If an ovary is removed before gonadotoxic treatment, it can be frozen and stored until the patient has overcome her disease.
When or if the patient experience ovarian failure, as a side-effect of the treatment, the ovarian tissue pieces can be thawed and autotransplanted. Upon transplantation the ovarian function will resume within 3-6 months and restore the ovarian function.
The technique has proven surprisingly robust, and transplantation of thawed ovarian tissue results in ovarian function for several years in most cases. 15 Danish children have been born as a result of this technique.
These children were born following transport of the ovarian tissue for a period of 4—5 hours prior to cryopreservation. One of these women, who were originally transplanted with six pieces of ovarian tissue, after having experienced a period of menopause, conceived again following natural conception. She have now given birth to three healthy girls from separate pregnancies being the first woman in the world to have had three children, as a result of transplanting frozen/thawed ovarian tissue.
So far, transplantion of thawed ovarian tissue in Denmark has been performed in a total of 80 girls and women who have all achieved resumption of ovarian function.
Cryopreservation (freezing) of ovarian tissue is the only fertility preserving option for:
- prepubertal girls who are not able to produce mature oocytes for oocyte freezing.
- and young woman who cannot postpone gonadotoxic treatment but have to initiate acute chemo – and/or radiation therapy.
Logistics
The Laboratory of Reproductive Biology is the only institution in Denmark performing cryopreservation of ovarian tissue, and since 1999 we have preserved around 1000 ovaries from young girls and woman aging 0.5-38 years. Currently, LRB performs around 80-100 cases of ovarian tissue annually in Denmark.