Let’s get this out there: no, technically, there’s no universal age limit for egg freezing—or any assisted reproductive technology. Guidelines vary from practice to practice. So why—or when—is a woman not a good candidate?

First, let’s delve into the factors that might prompt some doctors to set an egg freezing age limit.

Egg count and quality decline with age

Why impose an egg freezing age limit?

Women are born with their entire supply of eggs—approximately 1 to 2 million at birth. About half are gone by puberty, and by age 35, only about 6% of your eggs remain. As you get older, and your egg count decreases, it becomes more difficult for your ovaries to respond to the stimulation medication used during egg freezing and other fertility treatments, and you’re more likely to need multiple cycles to achieve a number of eggs that give you a good chance for pregnancy later.

It’s a dramatic decrease, but if you do the math, it may seem like there are still plenty of eggs left. But there’s something else to keep in mind: because your eggs age with you, the quality of the eggs you have is diminishing too, making them less likely to be chromosomally normal and able to create a healthy baby. Egg quality decline is directly correlated with age, and it’s pretty much inevitable. At age 40, less than 20% of your eggs are likely to be genetically normal.

So women experience a double whammy of fertility decline: as they age, they produce fewer eggs per cycle, and the eggs they do produce are less likely to be genetically normal. That’s why some doctors may impose an egg freezing age limit—if women freeze their eggs later, there’s a higher likelihood those eggs won’t fertilize when the time comes.

The Extend Fertility approach to the egg freezing age limit

Here at Extend Fertility, we don’t impose a strict age limit on egg freezing. We strongly encourage women to freeze before they’re 35 because that’s when the procedure is most effective and valuable for the women undergoing them. And we actively work to educate younger women—who experience a well-documented fertility knowledge gap—about their fertility timeline and their options, so they can make smart and proactive choices for their future.

However, because each woman’s circumstances and biology is different, our team has worked successfully with women in their late 30s and early 40s. There are two keys to freezing your eggs after age 35: freeze a larger number of eggs, and have a thorough understanding of the possible success rates.

How many eggs?

For women under 30, we recommend freezing at least 12 eggs. Women typically ovulate one egg each month, representing one chance at a possible pregnancy—so 12 eggs represents about a year’s worth of fertility. Because the majority of women under 30 are able to get pregnant within a year, freezing 12 eggs gives those women a 65–85% chance of motherhood with those eggs later on.

But because, as women age, there’s a lower chance of each individual egg being normal, we recommend freezing more eggs to achieve that same chance of pregnancy later on. For women 31–35, we recommend freezing 12–24 eggs. For women 35 and older, the data are more limited and less clear—while 12–24 eggs may be sufficient in many or even most cases, a cautious approach would be to aim for freezing 24 eggs or more. And, like we discussed above, that can take more cycles and more medication than it would for a younger woman.

So while there’s no age limit on egg freezing here, we do highly recommend freezing sooner, rather than later—it will increase your chances of success and decrease the dent in your pocketbook.

Thoroughly informed decision-making

One of our fundamental beliefs here at Extend Fertility is that women are smart. Seriously! If you give women accurate and thorough information about their health, in a way that makes sense to them, they’ll be able to make informed decisions that work for their own lives. (That’s part of the reason we offer fertility assessments: to allow women to better understand their fertility health.)

That’s also how we approach the issue of an age limit on egg freezing. We ensure that every woman, whether she’s 22 or 42, understands the true likelihood of egg freezing being an effective and successful treatment for them—so they can make their own decisions.

Here’s the latest research available on egg freezing success, based on age and number of egg frozen:

The probable success rate for egg freezing, based on age and number of eggs frozen. While Extend Fertility doesn’t set an age limit for egg freezing, we do counsel each woman so she understands how effective the procedure might be for her.

At age 37, freezing 24 eggs gives you an 80% chance of motherhood—but freezing just a few years earlier, at age 34, means you’d only need to freeze 12 eggs to have the same 80% chance of having at least one baby with those eggs later.

Learn more about egg freezing success rates.

That’s why we encourage women to freeze before they’re 35; there’s a higher chance of success. But for a woman who decides to freeze at 37, the procedure might still be helpful: this is the youngest her eggs will ever be. That’s the point—the decision is each woman’s to make for herself.

If you’re hoping to have children one day— but the time isn’t right now, this is the takeaway: there isn’t technically an egg freezing age limit, but the treatment is most effective and valuable for younger women. To learn more, contact us.