Op-Ed

Grayscale photo of two women who are sitting next to each other, looking at each other's smartphones.

New evidence shows that the tests many companies use to determine a woman's chances of having a baby are based on bogus science.

"Learn how many high quality eggs you have remaining and your chances of getting pregnant now and in the future,” beckons Egg-Q, one of the handful of new startups offering fertility testing to women concerned about their reproductive potential. The desire to know “how long you have left to conceive,” as offered by LetsGetChecked, or, more simply, “powerful information about your fertility,” courtesy of Modern Fertility, is understandable. Women are having children later than ever, a shift that has proved professionally and personally beneficial, but reproductively challenging. When offered a fertility magic eight ball, many can’t help but take a peek, hoping to discover something, anything, about their baby-making future.

If only that was possible.

These fertility blood tests provide women with an assortment of figures and graphs charting their ovarian reserve, along with a few other measures that will present themselves as authoritative, fate-determining even. But in reality, they offer little more than...