<p>Fertility protection before gonadotoxic therapy is an important aspect of interdisciplinary (oncological) care and is particularly significant for young patients. Possible options include cryopreservation of ovarian tissue, which began as an experimental method and is now an established procedure that is covered by health insurance under certain conditions. The advantage of this method is that it can be performed quickly when there is considerable time pressure due to the urgency of treatment. It is also the only option for prepubescent girls. In some cases, this method can still be used even after chemotherapy has already begun. After retransplantation of the tissue, spontaneous “natural” conception is possible, and the body’s own hormone production is maintained.</p>