P-141: Comparison Study The Effect of In Vitro Maturation and IVF Fertilization of Cryopreserved Oocyte with Fresh Oocyte in Mice

Background: Cryobiology and in vitro maturation of oocytes are very important tools of reproductive technology. Oocyte plays an important role in fertility. The objective of this research is comparison study the effect of invitro maturation and IVF fertilization of cryopreserved oocyte with fresh oocyte in mice. Materials and Methods: For this purpose, after superovulation was performed oocytes were isolated mechanically from the ovary and evaluated in three groups as follows: group A: fresh oocytes, group B: frozen oocytes. group A, B oocytes were transferred to TCM-199 tissue culture medium for in vitro maturation. Then isolated oocytes vitrified with rapid freeze-rapid thaw method. Fresh and freeze-thawed oocytes moved into culture medium and some factors were evaluated such as growth rate, destraction, cumulus expansion, for evalution of fertility‚ collected oocytes in each group were transferred to culture medium and sperms were added. 48 hours post insemination the number of fertilized oocytes was determined. Results: For this reason, oocytes were put into the CO2 incubator for 48 hours. The results demonstrated that growth rate of fresh group was better than frozen groups and oocytes with intact cumulus cells had better growth rate to metaphase II. In this research, oocytes with intact cumulus from high to low number were in groups A, B. Also growth rate was quite consistent with it and showed a significant difference between these groups. Conclusion: Quality of oocyte isolated from by using this method of freeze-thaw cause low growth rate than fresh of oocytes.