Protecting female fertility from cancer therapy.

Recent advances in cancer therapy have improved the long-term survival of young cancer patients who are then commonly faced with iatrogenic infertility and premature ovarian failure. Preservation of fertility potential has thus become a major goal and could be realized by preventing ovarian toxicity or by cryopreservation of reproductive cells (i.e. oocytes, embryos) and tissues (i.e. ovarian cortex). GnRH analogs prevent chemotherapy-induced-ovarian-damage in rats, however human results are controversial. Anti-apoptotic agents (i.e. sphingosine-1-phosphate) may present an innovative treatment to prevent oocyte destruction during cancer therapy. Although cryopreservation of mouse oocytes is successful, the results obtained in other mammalian species were worse, probably due to their extreme sensitivity to suboptimal conditions during the process of cryopreservation. This resulted in low oocyte survival and fertilization rates, a high incidence of polyploidy, and poor embryonic developmental ability. Ovarian tissue cryopreservation is currently considered as the optimal procedure for follicle banking. Transplantation offers the best prospect of using frozen-thawed ovarian tissue, since no reliable ovarian in-vitro culture technology exists.