Objective: To investigate the factors that might influence the success of an embryo freezing and thawing program. Method: The relationship between the pregnancy rate in 73 cycles of embryo freezing and thawing progr...Objective: To investigate the factors that might influence the success of an embryo freezing and thawing program. Method: The relationship between the pregnancy rate in 73 cycles of embryo freezing and thawing program and the following factors was analyzed: maternal age, E 2 level at the time of HCG trigger, embryo storage time, number of thawed embryos transferred, presence of sponsoring embryos and intact embryos. And the survival rate of thawed embryos with different morphology, cell stage and storage time was evaluated. Result: Transfer with three or more than three thawed embryos resulted in pregnancy rates of 38.5% and 35.7%, respectively, compared with 5.3% for transfer of fewer than three embryos. The presence of sponsoring embryos and intact embryos significantly increases pregnancy rate in embryo freezing and thawing program. No other factor examined had any effect on pregnancy outcome. The survival rate of good morphology embryos was higher than poor ones, but was not influenced by cell stage and storage time. Conclusion: Embryo morphology before freezing, number of thawed embryos transferred and the presence of intact embryos are important to the outcome of embryo freezing and thawing program.展开更多
The test of deep freezing (-196℃) preservation of mammalian embryos was applied successfully to mouse (for the first time) in 1972 (Whittingham, Leibo and Mazur, 1972), and subsequently to cattle (Wilmut and Rowson, ...The test of deep freezing (-196℃) preservation of mammalian embryos was applied successfully to mouse (for the first time) in 1972 (Whittingham, Leibo and Mazur, 1972), and subsequently to cattle (Wilmut and Rowson, 1973), sheep (Willad-展开更多
文摘Objective: To investigate the factors that might influence the success of an embryo freezing and thawing program. Method: The relationship between the pregnancy rate in 73 cycles of embryo freezing and thawing program and the following factors was analyzed: maternal age, E 2 level at the time of HCG trigger, embryo storage time, number of thawed embryos transferred, presence of sponsoring embryos and intact embryos. And the survival rate of thawed embryos with different morphology, cell stage and storage time was evaluated. Result: Transfer with three or more than three thawed embryos resulted in pregnancy rates of 38.5% and 35.7%, respectively, compared with 5.3% for transfer of fewer than three embryos. The presence of sponsoring embryos and intact embryos significantly increases pregnancy rate in embryo freezing and thawing program. No other factor examined had any effect on pregnancy outcome. The survival rate of good morphology embryos was higher than poor ones, but was not influenced by cell stage and storage time. Conclusion: Embryo morphology before freezing, number of thawed embryos transferred and the presence of intact embryos are important to the outcome of embryo freezing and thawing program.
基金This research was supported in part by Jia Jingxiao (贾敬肖), Shanxi Institute of Zoology
文摘The test of deep freezing (-196℃) preservation of mammalian embryos was applied successfully to mouse (for the first time) in 1972 (Whittingham, Leibo and Mazur, 1972), and subsequently to cattle (Wilmut and Rowson, 1973), sheep (Willad-
