The development of modern medicine made it more likely for oncological patients to survive. Also, there are a lot of young female patients with a persistent wish for kids. After an aggressive chemotherapy, premature ovarian failure (POF) is a possible consequence of the therapy. Therefore, efficient fertility protective interventions are requested. The transplantation of ovarian tissue after cryopreservation is a valuable method, which could remain fertility after POF induced by cytotoxic therapies. Especially for girls suffering from cancer, who didn't reach puberty yet, cryopreservation of ovarian tissue is the only opportunity to preserve a chance of restoring fertility after POF.~There are two locations, which could be used for the retransplantation of the cryopreserved tissue: the remaining ovary and the pelvic wall. Both, the ovary and the subperitoneal pocket in the pelvic wall present a location, where the maturation of follicles is possible. The remaining question is: where do more follicles grow? To answer this question, a study will be necessary. The purpose of this study is to determine whether the pelvic wall or the ovary represents a better location for the maturation of follicles in the context of ovarian transplantation after cryopreservation of ovarian tissue before cytotoxic therapies.~Interventions:~Ovarian tissue will be transplanted into two different locations; subperitoneal into the loge of the adnexa of uterus and contralateral into the ovary. The assignment of the two parts of ovarian tissue to the place of transplantation (pelvic wall vs. ovary) will be randomised. The study-specific interventions include:~Transplantation of the same amount of ovarian tissue into both locations~Monthly sonographic controls and determination of estradiol, LH, FSH and progesterone from the 3rd on to the 12th month after the transplantation. Therefore, blood samples will be made.~Monthly documentation of the duration of the cycle from the 3rd on to the 12th month after transplantation~One year after the transplantation, the investigators will be able to determine which location is more likely to grow follicles. With the gained knowledge, standardized recommendations could be formulated which help to improve the whole process of medical care of female oncologist patients.
The purpose of this study is to determine whether the pelvic wall or the ovary represents a better location for the maturation of follicles in the context of ovarian transplantation after cryopreservation of ovarian tissue before cytotoxic therapies.