In vivo fate mapping of cryopreserved murine ovarian grafts

BACKGROUND: Cryopreservation of ovarian tissue has been suggested as an alternative to restore fertility for ovarian failure before chemotherapy. METHODS: Ovaries of donor FVB/N-Tg (PolII–Luc) Ltc transgenic mice (n = 5) were cryopreserved and transplanted to the back muscles of recipient FVB/NJNarl wild-type mice that had undergone bilateral oophorectomy. We evaluated the fate of cryopreserved murine ovarian grafts by in vivo bioluminescent imaging (BLI), AMH mRNA expression and follicle counts. RESULTS: There were significantly stronger BLI signals in the fresh ovaries than in the frozen–thawed ones. The number of primordial follicles was significantly lower in frozen–thawed ovaries at 10 days after transplantation (P < 0.001). The AMH mRNA expression was significantly lower in the frozen–thawed ovaries (P < 0.001), showing that unavoidable harm occurs after transplantation. CONCLUSIONS: Ovarian cryopreservation by slow freezing compromises ovarian reserve by cryoinjury and ischemia, evident at an early stage after transplantation.