Effect of different sites for cryopreserved ovarian tissue implantation in rabbit.

BACKGROUND Autotransplantation of frozen-thawed ovarian tissue has proven to be an effective method to restore endocrine function and fertility. But it remains to be studied which site and which method is most effective and practical. We therefore implanted small pieces of cryopreserved ovarian tissues into different sites in rabbits to find the optimal position. METHODS Fifteen New Zealand white female rabbits were randomly divided into three groups. In group 1, fresh ovarian tissues were implanted into the mesometrium and ovarian bursa. In group 2, cryopreserved ovarian tissues were implanted into the mesometrium and ovarian bursa. In group 3, cryopreserved ovarian tissues were implanted into the preserved ovary. RESULTS There were no significant differences among the three groups as to the proportions of normal and morphologically changed follicles in implanted ovarian tissues. The implanted ovarian tissues in the three groups did not show any evident changes in histology and ultrastructure, and all resumed follicle development and revealed maturescent follicles. CONCLUSIONS Cryopreservation and implantation of small pieces of ovarian tissues are feasible. Generally, the mesometrium, ovarian bursa and ovary are all available sites for implantation and have similar rates of acceptance, despite some differences in the details of implantation.