17,494 women, 158 countries: what perimenopause actually feels like isn't what we're told to expect

The study, "Global perspectives on perimenopause: a digital survey of knowledge and symptoms using the Flo application" ↗, was published in July 2026 in Menopause, the journal of The Menopause Society. Researchers from the Mayo Clinic worked with the cycle-tracking app Flo to survey 17,494 women aged 18 and over across 158 countries — 12,681 of them aged 35 or older. It is, as far as the authors can tell, the first attempt to compare perimenopause knowledge and symptoms across this many countries at once.

The headline result is a mismatch. When asked what they knew about perimenopause, women most often named hot flashes (71%), sleep problems (68%) and weight gain (65%). But when women aged 35 and over described what they were actually experiencing, the list came out in a different order: fatigue (83%), physical and mental exhaustion (83%), irritability (80%), depressive mood (77%), sleep problems (76%), digestive issues (76%) and anxiety (75%). Hot flashes — the thing almost everyone associates with the transition — didn't lead the list of lived symptoms at all. Among the narrower group of women 35+ who said they were currently in perimenopause, the same symptoms ran higher still, with exhaustion at 95% and fatigue at 93%.

That gap has a practical cost. A symptom you've been told to expect is one you can name, look up and take to a doctor. Fatigue, low mood, poor sleep and digestive changes have no such label attached — they get filed under stress, overwork, low iron, thyroid, anxiety, or simply getting older. The authors' own conclusion is a discordance between what women know about perimenopause and what they experience, and they argue the practical fix is better symptom recognition rather than more awareness of hot flashes specifically. Knowledge also varied significantly by region (P<0.001), with the UK, Ireland, Canada, Australia and the Netherlands scoring highest and the United States sixth.

For women managing diabetes or blood sugar, this list is worth reading twice. Fatigue, exhaustion, poor sleep, irritability and digestive changes are also, more or less exactly, the symptoms of blood sugar running high or swinging — which means during perimenopause the two can mask each other in both directions. Falling oestrogen genuinely does change insulin sensitivity, so it isn't a matter of picking one explanation over the other. It's a reason to keep testing rather than assume, and to raise perimenopause explicitly with a clinician if a cluster of these symptoms is new and doesn't match your usual pattern.

The study's limits are worth being straight about. This is a cross-sectional survey of people who had already chosen to use a period-tracking app — a group likely to be younger, more health-engaged and more cycle-literate than women in general, and to own a smartphone. It can't tell you how common perimenopause symptoms are worldwide, and it can't establish that the hormonal transition caused any particular symptom, because nothing here was clinically confirmed or followed over time. What a sample this size and this geographically spread can show well is the shape of the gap between expectation and experience — and that gap is consistent enough to be worth acting on.

What the research says