How about the fertility capacity of frozen eggs?
November 20, 2015
Before we decide to cryopreserve our own eggs for the future use, we must think about the impact of freezing.
According to many scientific articles, the risk of egg freezing is related to the maternal age, not the procedure itself. The findings are concordant to the report released by Stork Fertility Center in 2011 annual meeting of Taiwan Society of Reproductive Medicine.
We divided the women with a cut-off age at 38 years, and observed the fertility capacity between the fresh and thawed eggs. No significant differences were found between the thawed and fresh eggs. However, the clinical pregnancy rate was 44.6% in the women under 38 years, but only around 28% in the women over 38 years.
Actually, the protocol of freezing or thawing a mature egg is quite similar to that of an embryo (vitrification is now prevalent). However, those eggs harvested from the women with advanced ages have lower tolerance to the freezing and thawing due to the structural fragility, chromosomal aberration or other biological declines. If a woman freeze her eggs at 29 years of age, she can use these 29-year-old eggs when she is 40. If a woman freeze her eggs at 39 years of age, she can only use these 39-year-old eggs no matter how fast she thawed them.
Therefore, many experts recommended to freeze the eggs as young as possible. Again, the fertility capacity of eggs is not affected by the freezing procedure, but by the maternal age.
To understand the principle of egg freezing, please watch the following video: