Restoration of ovarian activity and pregnancy after transplantation of cryopreserved ovarian tissue: a review of 60 cases of reimplantation

Aggressive chemotherapy/radiotherapy and bone marrow transplantation can cure >90% of girls and young women affected by disorders requiring such treatment. However, the ovaries are very sensitive to cytotoxic drugs, especially to alkylating agents. Several options are currently available to preserve fertility in cancer patients. The present review reports the results of 60 orthotopic reimplantations of cryopreserved ovarian tissue performed by three teams, as well as 24 live births reported in the literature to date. Restoration of ovarian activity occurred in almost all cases in the three series. Among the 60 patients, eleven conceived and six of those had already delivered twelve healthy babies. In the future, we are looking to: 1) improve freezing techniques; and 2) enhance the "vascular bed" before reimplantation to increase pregnancy rates. On the other hand, cryopreservation of ovarian tissue may be combined with removal, via puncture, of small antral follicles, making it possible to freeze both ovarian tissue and isolated immature oocytes.