Fertility and reproductive medicine is constantly changing and expanding as its technology rapidly advances. Freezing a woman’s eggs can be of great benefit for many conditions such as cancer and infertility.
Initially, a woman’s eggs, which are called oocytes, were frozen with moderate success. Ice crystals formed within the oocyte which caused damage and left the egg unusable.
A different freezing process was formulated which froze the oocyte at a much slower rate, which helped to prevent ice crystal formation. This method, however, had much lower rates of fertilization.
A new method, called vitrification, rapidly cools the oocyte at a rate of 20,000 degrees Celsius per minute!! The freezing occurs so quickly that it does not allow ice to form. This leads to improved oocyte survival and function, fertilization, and pregnancy rates. Chromosomal analysis of embryos of previously frozen oocytes versus normal oocytes revealed no difference in incidence of chromosomal abnormalities or congenital anomalies.
The new egg freezing technology is very exciting, and we are continuing to learn ways to apply this to both infertile and fertile women!