An option to optimize the future ability to conceive

Celebrities do it.

Apple and Facebook now offer it as a health benefit for female employees.

So what is egg freezing, and who should consider it?

Egg freezing, originally developed for patients facing cancer treatment, is becoming increasingly mainstream. Women are born with the maximum number of eggs that they will ever have, and that egg number and quality gradually decrease as a woman ages. But completing a higher education degree, climbing the corporate ladder, meeting a soulmate and establishing financial stability all take time. Many women who want to optimize their future ability to conceive are turning to egg freezing.

How It Works

A woman has a group of antral follicles that are recruited every month. Eggs grow inside these follicles, but not every follicle contains an egg. During the natural menstrual cycle, hormones from the brain are released that allow only one follicle in a group of follicles to become the dominant follicle. During ovulation, which is typically monthly, each dominant follicle releases a single egg. The other follicles are lost through a process called atresia.

In an egg-freezing cycle, combinations of reproductive hormones are given in higher doses than what the body naturally produces. This allows for many antral follicles to grow and develop during a single month, so multiple eggs can be retrieved and frozen.

The Freezing Process

This is newer technology, so it is unclear how long eggs can be frozen. However, it is believed that they can stay frozen for many years with vitrification, which is the way that eggs are frozen now.

The number of eggs frozen depends on age. In general, the older a person is, the more eggs would need to be frozen to increase chances at having a baby.

It is also possible to create and freeze embryos (fertilized eggs) using the sperm of a partner or donor.

Effects of Egg Freezing

Eggs that are removed from the ovary during an egg freezing cycle are eggs that would otherwise have been lost. Undergoing a single cycle, or even multiple cycles, of egg freezing:

• Does not decrease overall fertility
• Does not speed the loss of egg supply
• Does not cause women to enter menopause earlier

Egg freezing may increase the chance of having a child in the future. However, there are no guarantees. To learn more about your options, visit fertility.nm.org.

- Mary Ellen G. Pavone, MD, IVF medical director, Northwestern Medicine Fertility and Reproductive Medicine.