Turns Out Ovarian Reserve Testing Isn't Totally Reliable

Every Lean In Group in America has at one point discussed the possibility of freezing one’s own eggs. Since women are only born with a set number of eggs that die off regularly, the procedure can be a good choice for women who are, for whatever reason, not ready to have children when their egg supply begins to rapidly decline—a point which, for most women, begins around the age of 35. One snag: the test that theoretically tells a woman how many eggs she has left can be extremely difficult to decipher and might lead women who have plenty of eggs to panic—or vice versa.

NPR’s Eliza Barclay reports:

The ovarian reserve test was originally developed to measure egg supply in women who were struggling to get pregnant — not in women who wanted to freeze their eggs. Doctors realized that some of these women could benefit from ovarian stimulation to produce eggs to use in in vitro fertilization because they still had a lot of eggs left. Those women responded well to hormones… (Women undergoing egg freezing and women doing IVF undergo the same ovarian stimulation process to make eggs — the difference is that the IVF patients usually use their eggs right away.)

In an interview with NPR, Dr. Samantha Pfeifer, an associate professor at Weill Cornell Medical College and committee chairperson at the American Society for Reproductive Medicine, spoke about the test’s potential unreliabilit.

“These tests do not tell me how many eggs are left,” she said. “They can generally give you a sense of are there a lot of eggs there or fewer eggs remaining, but they’re not really predictive of when someone is going to go through menopause or be able to achieve a pregnancy.”

Adam Balen, chair of the British Fertility Society, echoed Pfeifer’s concerns in an interview with The Guardian, and noted that a big predictor of fertility can be one’s mother’s history—in particular, the age at which she went through menopause.

Experts from the fertility industry unsurprisingly argue that testing is a good idea to help make women more aware of their fertility—the worst case is forgoing the test and finding out you have too few good eggs when it’s already too late.

“Ideally we’d love to know how can we predict who should freeze their eggs, for example, or who should try and get pregnant sooner; who should do something sooner because their fertility decline faster than expected,” Pfeifer continued. “And if we can say these people don’t have to freeze their eggs because they should have no difficulty getting pregnant well into their late 30s—well, that’d be great to know that.”