Its timing and severity also vary enormously from person to person. Some women experience extreme hot flashes, disrupted sleep and brain fog; others notice little. One woman may enter natural menopause at 45, another at 54. Both ages fall within the normal range, yet that timing can affect health in distinct ways.

Many of these differences remain poorly understood. Electronic medical records, the researchers note, offer an unmatched opportunity to close those knowledge gaps, because they allow scientists to study routinely collected data from hundreds of thousands or even millions of people.

Large-scale analyses of such data could shed light on how menopause symptoms change over time and who is most likely to experience them; how markers of heart disease, bone health or mental health track with the menopausal transition; and how social determinants of health — such as ethnicity and access to health care — shape a woman's lived experience of menopause.

Why is menopause so rarely recorded?

The study is not the first to note that menopause status and symptoms are inconsistently documented in health care settings. But it systematically highlights the sheer size of the problem, showing that menopause often does not appear in records at all.

The reasons remain unclear. The researchers offer several possibilities. Because menopause is not a disease, clinicians may simply not think to enter it as a diagnostic code. It may feel too obvious or too irrelevant to note. Patients themselves may not raise the subject unless their symptoms are severe. Health care providers do routinely ask middle-aged patients about reproductive health — for instance, when they had their last menstrual period — but that information rarely makes it into the electronic record.

These explanations remain hypotheses; the study did not determine which factors are most responsible.

Plans to close the gap

As the researchers see it, failing to capture this information is a colossal missed opportunity to advance research and personalize care. Their team is now working on several fixes.

One is a short, simple questionnaire about menopause status and symptoms that patients could fill out when checking in for medical appointments. The responses would then be added to their records, where both their health care team and researchers could use them. The team is also developing a computer-based method to infer menopause-related information from other data in a woman's health record or genetics.

In addition, the researchers are mining the All of Us dataset for systematic differences — in patients' cultural background, income level, specific health system practices, or urban versus rural settings — that might predict whether menopause data gets recorded at all. Those associations could point to targeted ways to encourage its collection.

The underlying logic is simple, the researchers write: it is impossible to research, and to treat, what is not measured. Capturing the menopause transition, they argue, is an essential step toward improving health care for women in midlife.