OVARIAN TISSUE CRYOPRESERVATION FOR THE SAFEGUARD OF FEMALE FERTILITY

Ovarian tissue cryobanking is considered an available method for preserving female fertility and represents the best option in young pre-pubertal cancer patients. Cryopreservation can be performed on ovarian cortical fragments or on the entire organ. To move forward, the cryopreservation of both avascular ovarian fragments and of whole ovaries must be improved. To this purpose, we performed a detailed comparison between conventional slow freezing and directional freezing on both cortical fragments and whole ovary. We provide that directional freezing improves the viability of cryopreserved ovarian tissue both in whole ovaries and cortical fragments, but we observed a better preservation of follicles when the samples were frozen as entire organ. We also developed a perfusion system for ex vivo culture of whole ovary demonstrating that it is possible to maintain alive sheep ovary outside the body for up 4 days. This perfusion culture system could provide a future alternative for women at risk of ovarian involvement due to the threat of reintroducing malignant cells.