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 untangle the timing:

• Menopause — the point 12 months after your last period (average around 51)
• Perimenopause — when symptoms typically start, commonly in the mid-forties but sometimes the late thirties
• Early menopause — menopause before 45
• Premature ovarian insufficiency (POI) — before 40, affecting around 1 in 100 women and needing medical attention

Genetics is the biggest influence on timing, so 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 is a wide normal range, and "early" symptoms in your forties are far more common than many women expect. It is also worth knowing that an earlier menopause matters beyond the symptoms themselves: oestrogen helps protect bone and heart health, so losing it sooner means those longer-term considerations come into focus earlier, which is part of why POI and early menopause are actively treated rather than simply monitored.

The length of the run-up varies as much as its timing. Perimenopause can be as short as a year or stretch beyond eight, and smoking tends to bring the whole timeline forward by a year or two. If you cannot track your periods, because of a hysterectomy or hormonal contraception, doctors often go by age and symptoms instead, treating around 51 as the likely point.

What to do: if you are in your forties with changing periods and symptoms, that is typical perimenopause timing, so there is no need to wait, and you can map your symptoms with our free hormone quiz before seeing your GP. If you are 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. The signs to look for are set out in the first signs of perimenopause.