How cryopreservation (egg freezing) can help preserve your fertility

There are many reasons why you might want to consider fertility preservation. Perhaps you haven’t yet met the person you want to have a family with. Or you’re focused on another important part of your life, like your education or career. Maybe you’re undergoing medical treatments or being deployed overseas, and you want peace of mind knowing the option is available if needed. Whatever your reason, freezing eggs, sperm, or embryos—called cryopreservation—may be a good option if you’re not ready for children now, but may want them in the future.

How does cryopreservation work?
In cryopreservation, very low temperatures are used to preserve eggs, embryos, and sperm. Your gametes and/or embryos will be mixed with a special “anti-freeze” solution, cooled, and stored in liquid nitrogen. When they are ready to be used, the gametes or embryos will be thawed.

The cryopreservation process used to freeze eggs, sperm, and embryos is usually one of the following.

Slow freezing

During slow freezing, the temperature of the eggs, sperm, or embryos is lowered in a protective agent or substance using a computer-controlled rate in a series of steps, to a very low temperature.

Vitrification

In vitrification, or flash freezing, the temperature of the eggs, sperm, or embryos is lowered very rapidly to an extremely low degree. This solidifies the sample into a glass-like state and avoids the risk of ice crystals forming.

Different labs may use different methods for freezing eggs, embryos, and sperm. Before choosing a facility, ask about their cryopreservation technology, processes, and success rates. This customizable tool can help organize your thoughts and guide your discussion.

Learn more about the differences between embryo and egg freezing.