I-11: Cryopreservation and Utilization of Ovarian Tissue: When, Where and How?

In women, around 10% of cancers occur in those younger than 45 years old. Although aggressive chemotherapy/radiotherapy and bone marrow transplantation can cure more than 90% of girls and young women affected by disorders requiring such treatment, the ovaries are very sensitive to cytotoxic drugs, especially to alkylating agents. Therefore, these treatments can result in premature ovarian failure, depending on the follicular reserve, the age of the patient and the type and dose of drugs used. Several options are currently available for the preservation of fertility in cancer patients: embryo cryopreservation, oocyte cryopreservation or ovarian tissue cryopreservation. The choice of the most suitable strategy for preserving fertility depends on different parameters: the type and timing of chemotherapy, the type of cancer, the patient's age and the partner status. Fertility preservation needs to be completed before chemotherapy and/or irradiation is started and might take 2-3 weeks with established techniques such as embryo or oocyte cryopreservation. Cryopreservation of ovarian tissue is the only option available for prepubertal girls and woman who cannot delay the start of chemotherapy. So far, more than 30 live births have been obtained after orthotopic transplantation of cryopreserved ovarian tissue. Apart from the candidates for ovarian tissue cryopreservation, we will also discuss the procedures to freeze ovarian cortex and where we should transplant such pieces of tissue. Finally, results and possible future approaches will be reviewed.