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Comparison of the embryo development and clinical pregnancy rates between vitrified and fresh oocytes

Comparison of the embryo development and clinical pregnancy rates between vitrified and fresh oocytes
AuthorHsing-Hua Lai, Huai-Ling Wang, Wen-Yi Chiang, Yao-Cheng Huang, Saing-Chi Chen, Wan-Jung Hsieh, Chun-Chuan Chen, Chi-An Hsieh, Shih-Chieh Huang, Ya-Hui Hsu, Hsin-Hua Chou
EditorShih-Chieh Huang
Seminar name2012 TSRM
Keywordvitrification, cryo-oocyte, pregnancy rate
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In recent years, oocyte cryopreservation is mainly performed before oncological treatment, but rarely for infertile cause. For non-oncological purpose, such as single women with advanced age, autoimmune disorders, or for couples with male infertility, oocyte vitrification could retain the possibility of future utilization.
To assess the clinical practicality, we compared vitrified and fresh oocytes in their embryo development and pregnancy rates with our clinical data.

Study design

Patients’ characteristic

Fresh D3ETWarmed D3ET
Cycle no.4024
Average age (y/o)36.535.8
Total MII oocytes used288176
Average MII oocytes used per cycle7.27.3
Total embryos transferred10963
Average embryos transferred per cycle2.72.6


》In warmed D3ET group, oocytes were vitrified for several months to one year. The post-warming survival rate was 88.6%.
》The embryo development and pregnancy rate of both groups were listed in the table and figure below:
Fresh D3ETWarmed D3ETχ2-test
Fertilization rate80.1%72.4%NS (p=0.10)
Day3 good embryo rate52.2%50.8%NS (p=0.91)
Clinical pregnancy rate42.5%37.5%NS (p=0.89)
Implantation rate18.3%17.5%NS (p=0.85)

As shown in the figure, yellow bar represent warmed D3ET group and orange bar represent fresh D3ET group. No statistical difference between warmed and fresh groups in FR, D3GER, CPR and IR.


Our results showed that the cryo-oocyte treatment is feasible in clinical practice, in consideration of the comparable fertilization and embryo development rates as well as IR and CPR to those of conventional IVF treatment. We suggested that it may be applied for patients with non-oncological purpose.
Stork Fertility Center送子鳥 Stork Fertility Center送子鳥 Author