At what age does menopause start?

Menopause happens at an average age of around 51, but the normal range is roughly 45 to 55 — and perimenopause, the run-up, usually begins several years earlier, often in your mid-forties.

A few definitions help. Menopause itself is the point 12 months after your last period (average around 51). Perimenopause — when symptoms typically start — commonly begins in the mid-forties but can start in the late thirties. Menopause before 45 is called early menopause, and before 40 it's premature ovarian insufficiency (POI), which affects around 1 in 100 women and needs medical attention. Genetics is the biggest influence on timing (your mother's age at menopause is a rough guide), while smoking tends to bring it forward, and some surgery or medical treatments can cause it suddenly.

So there's a wide normal range, and “early” symptoms in your forties are far more common than many women expect.

What to do: if you're in your forties with changing periods and symptoms, that's typical perimenopause timing — no need to wait. If you're under 45 (and especially under 40) with menopausal symptoms or absent periods, see your GP, since earlier menopause should be assessed and often treated, partly to protect long-term bone and heart health.