O-5: Endocrinological and Morphological Evaluation of Vitrified-Warmed Ovarian Tissue

Background: Our aim was to evaluate the recovery rate of ovarian function and the activity of hypothalamus-hypophiseal- gonadal axis following transplantation of vitrified ovaries. Materials and Methods: Five weeks-old female Wistar Rats were distributed randomly in two experimental groups; Fresh Transplanted, Vitrified-Transplanted and 8 weeks-old female Wistar rats were considered as control group. Also, bilateral Ovarectomized rats were used for hormonal assessment as a sham group. In gonadectomized fresh transplanted group, excised right ovary was immediately autotransplanted under the cervical skin and in gonadectomized vitrified-transplanted group; excised ovarian tissue was vitrified by combination of EG and DMSO (in V1and V2, 7.5 and 15% of both cryoprotectants was used respectively) and after performance of 3step warming, transplanted at the same site. In both transplantation groups, 3 weeks after transplantation, blood was collected by cardiac puncture and serum Gonadotropins, Estradiol (E2) and Progesterone Concentration was determined by direct immunoassay by use of ELISA kit. Also, in all experimental groups, follicular count was evaluated by using histological analysis. Results: Although serum E2, progesterone and gonadotropins concentrations in the fresh-transplanted and vitrified-transplanted groups were as the same as the control, serum E2 and progesterone level was increased and Gonadotropins level was decreased significantly as compared to the bilateral Ovarectomized group. In addition, preantral, antral and corpus luteum (CL) rate had increased in fresh-transplanted and vitrified- transplanted group in comparison to the control groups. Conclusion: It could be concluded that although ovary Vitrification and autotransplantation reduced the rate of small sized follicles (primordial and primary), vitrifiedtransplanted ovarian tissue can resume its function and this was proven properly by hypothalamus-hypophisealgonadal axis activity resumption.