With the explosion of media coverage regarding elective egg freezing for social reasons, I have found many patients and colleagues asking the question: What is the best age to freeze your eggs?

Of course, the obvious answer is when you still have them – meaning before you run out of good eggs! And women begin running out of good eggs from the moment they are born.

However, we can be much more scientific about our answer thanks to a recent article coming out of the University of North Carolina Chapel Hill published in the Fertility and Sterility journal.

This elegant study used several databases to calculate the optimal time for elective egg freezing. They used models that looked at the probability of marriage from the National Survey of Family Growth, the probability of natural conception from The Time to Conceive database, and they looked at the CDC SART data and the Integramed data on IVF. After analyzing all this information they were able to create an algorithm to predict at different ages the chances that freezing your eggs would result in a baby.

There were several important take-home points from this article

1. The greatest success from freezing your eggs was achieved in women who are less than 35 at the time of egg freezing. If your whole goal is to achieve the highest chance of having a baby, you should freeze your eggs before your 35th birthday.
2. The second important conclusion was that the greatest cost benefit of egg freezing was for women who froze their eggs at age 37 but did not get married or attempt pregnancy for seven years.
3. A third important point was that egg freezing at any age less than 40 years old created possibly the only chance to have a genetic child for some women, especially if they waited until their 40s to try to conceive.

This study will help us better advise the next generation of 20- and 30-somethings that are considering this new technology to preserve their chance of having a baby when they’re ready