FERTILITY PRESERVATION: Follicle reserve loss in ovarian tissue transplantation.

Ovarian tissue cryopreservation and transplantation (OTCP-TP) has progressed over the past decade from a revolutionary experimental procedure to a well-accepted treatment in many centers for young patients with a high risk of ovarian failure after cancer treatment. The procedure is remarkably successful, with studies reporting return of ovarian function in up to 95% of graft recipients and pregnancy rates of between 30 and 50%. The most significant limitation of OTCP-TP is the massive loss of follicles that occurs following transplantation, which is primarily attributed to ischemic damage and follicle activation. We review the current approaches to reducing follicle loss and maximizing graft lifespan via pharmacological agents which reduce ischemic damage and follicle activation. We further discuss the value and disadvantage of inducing follicle activation in the graft as a means of generating mature follicles in the immediate short term.