When will I hit menopause? How many more years will I be able to get pregnant? Many women ask themselves these questions, especially if they are planning to combine a family life with a professional career.

Scientists are trying to help women find answers. MaryFran Sowers and her colleagues from the University of Michigan in Ann Arbor are using a range of variables, including age and hormone levels, to predict the time window in which a woman is likely to hit menopause. The method they have developed has been published but is far from being packaged into a commercial test. Meanwhile, at least one European company is already selling a mail-order fertility kit: the PlanAhead Fertility Test, which according to the company can estimate the number of eggs remaining in the ovaries based on hormone concentrations.

This idea of precisely predicting menopause is appealing, but a one-size-fits-all test may not work for every woman, cautions Sowers. Factors such as obesity, diabetes and smoking might affect a woman’s fertility and the age she reaches menopause. Sowers is now beginning to study these special subpopulations.

There are clear benefits to knowing when menopause is coming. A woman who knows she is likely to soon lose the cardiovascular and bone benefits of reproductive hormones might be motivated to cut saturated fats and cholesterol from her diet, for example. But there may be instances in which knowing the future could lead to risky decisions. Suppose a woman takes a menopause predictor test and learns that she isn’t likely to reach menopause until age 55. She may delay childbearing until age 40, when her chances of developing gestational diabetes and placental problems are significantly higher. Research also shows that women over 40 are about 40% more likely than younger women to deliver early, and premature babies face a higher risk of developing chronic lung disease and other health problems. Will menopause tests lead to more high risk pregnancies?

For more of the latest news on fertility and reproduction, please see Nature Medicine's November special on reproductive medicine.

Photo by Morten Liebach