Restoration of ovarian function in orthotopically transplanted cryopreserved ovarian tissue: a pilot experience

Cryopreservation of ovarian tissue is currently proposed to young cancer patients before chemo- or radiotherapy to preserve their fertility. In this study, ovarian cortex was removed by laparoscopy from five women and cryopreserved before chemotherapy. After chemotherapy, they all experienced amenorrhoea due to premature ovarian failure and requested reimplantation of their cryopreserved ovarian tissue several years later. Thawed fragments were then grafted to an orthotopic site in all five women. Two of them underwent a second reimplantation. Ovarian function recovery was evaluated by hormone concentration measurement, follicular development on ultrasound and menstruation recovery. The first signs of ovarian function restoration (oestradiol peak, decrease in FSH, ultrasound showing follicular development) occurred between 16 and 26 weeks after reimplantation. Elevated FSH concentrations were sometimes observed between series of consecutive ovulatory cycles, demonstrating the presence of a relatively low ovarian reserve. There were no signs of disease recurrence in any patients with malignant disease. In conclusion, restoration of ovarian function was observed in all cases. Grafts remained functional in all the women. Transplantation of cryopreserved ovarian tissue to an orthotopic site appears to restore ovarian endocrine function, without any signs of disease recurrence.