Effects of the Stepwise Exposure Treatments Before Freezing on the Survival Capacity of the Frozen-Thawed Mouse Mature Oocytes by Vitrification or Ultra-Rapid Freezing.
- Author:
Sang Woo KIM
;
Young Ah LEE
;
Man Soo YOON
;
Kyu Sup LEE
;
Jae Ik LEE
;
Mi Kyung KIM
- Publication Type:Original Article
- MeSH:
Animals;
Blastocyst;
Cryopreservation;
Fertilization;
Freezing*;
Humans;
Mice*;
Oocytes*;
Vitrification*
- From:Korean Journal of Fertility and Sterility
2000;27(2):191-200
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
OBJECTIVE: This study was carried out to compare the effects of the stepwise exposure treatments on the morphological normality, fertilization and blastocyst formation rate of the frozen-thawed mouse mature oocytes by vitrification or ultra-rapid freezing and to use as a fundamental data for the cryopreservation of human oocytes. MATERIALS AND METHODS: The morphological normality and fertilization rates of the vitrified and ultra-rapid frozen mouse mature oocytes after three-stepwise exposure treatments (1step, 3step and 5step) were observed. After choosing the 3step exposure treatment groups, we observed the morphological normality and fertilization, blastocyst formation rate vitrified and ultra-rapid frozen mouse mature oocytes. RESULTS: The morphological normality and fertilization rates of the vitrified mouse mature oocytes after three-stepwise exposure treatments (1step, 3step and 5step) were 75%, 85%, 88% and 58%, 61%, 54% respectively. There were no significant differences among treatments (p>0.05). The morphological normality and fertilization rates of the control was 92% and 65%. There were no significant differences in fertilization rate among control and treatments (p>0.05). The morphological normality and fertilization rates of the ultra-rapid frozen mouse mature oocytes after three-stepwise exposure treatments (1step, 3step and 5step) were 83%, 83%, 84% and 75%, 63%, 56% respectively. There were no significant differences among treatments (p>0.05). The morphological normality and fertilization rate of the control was 95% and 67%. There were no significant differences among control and treatments (p>0.05). The morphological normality and fertilization rate of the vitrified or ultra-rapid frozen mouse mature oocytes after 3step exposure treatment were 69% and 75%, respectively. The blastocyst formation rate was 60% and 57%. The results did not differ significantly between vitrification and ultra-rapid freezing (p>0.05). CONCLUSION: As known in the above results, there were no significant differences in the fertilization and blastocyst formation rate of the frozen-thawed mouse mature oocytes by vitrification or ultra-rapid freezing among the control and treatments. It is suggested that vitrification and ultra-rapid freezing method were effective for the cryopreservation of mouse mature oocytes.