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!
…..There is a recent report from the American Society of Reproductive Medicine which states that oocyte cryopreservation is now an officially sanctioned option for young women with special fertility needs. Sperm and embryo freezing have been available and used successfully by infertility specialists for many years, but the techniques for egg freezing/warming is now a viable option in special conditions. The latest studies reveal an equal IVF (in vitro fertilization) successful pregnancy rate with the use of fresh eggs or frozen eggs.
…..Egg freezing can be considered to help women with the following conditions, which may endanger their fertility:
- A young woman about to undergo chemotherapy for a cancer; the medications can be toxic to her eggs
- A young woman with any condition that points towards early ovarian failure
- An IVF cycle where eggs are available but sufficient sperm is not available
- Some couples involved with IVF treatment do not want to freeze extra embryos
…..There is a new controversy arising from this available technique. As we are all aware, childbearing in our society is being delayed to later in a woman’s life for many individual reasons. Should egg freezing be considered to help ensure fertility success for some time later in a woman’s life?