Recovery of natural fertility after grafting of cryopreserved germinative tissue in ewes subjected to radiotherapy

Objective: To recover natural fertility of ewes that were subjected to ovarian failure induced by radiotherapy with an autologous orthotopic graft of cryopreserved germinative tissue. Design: Experimental surgery study. Setting: University hospital unit. Animal(s): Adult ewes. Intervention(s): Four ewes were submitted to right oophorectomy and posterior dissecting and freezing of the germinative tissue. Afterward, they were administered radiotherapy to induce infertility on the remaining left ovary. Later, two of the ewes had the thawed fragments of the right ovary injected inside the cortex of the irradiated left ovary in a "sowing" procedure that eliminated the need for sutures. Main Outcome Measure(s): Recovery of fertility in ewes after transplantation of germinative tissue into the ovary destroyed by radiotherapy. Result(s): The ewes were housed with fertile rams. Six months following the grafting, the rams impregnated the transplanted ewes. More than 2 years after radiotherapy, the nongrafted (control) ewes have not become pregnant. Conclusion(s): Intracortical grafting of the germinative tissue circumvents the obstacle of vascular anastomosis with autologous ovarian implants. Patients could benefit from the subcortical grafting of germinative tissue in one of the ovaries, recovering fertility after radiotherapy treatment for malignancy. (C) 2004 by American Society for Reproductive Medicine.)