What are the first signs of perimenopause?

The earliest signs of perimenopause are usually changes in your periods — they get shorter, longer, lighter, heavier, or less predictable — often alongside new sleep problems, mood changes, and the first hot flushes.

Because progesterone tends to fall first, some of the very earliest hints are disrupted sleep (especially waking around 3–4am), heightened PMS, new anxiety or irritability, and breast tenderness — sometimes years before periods change much. As oestrogen starts to fluctuate too, the more familiar symptoms appear: irregular cycles, hot flushes and night sweats, brain fog, joint aches, lower libido, and mood changes. Many women are caught off guard because they expect perimenopause to arrive later and look more dramatic than it does.

It typically begins in your forties (sometimes late thirties) and is diagnosed on your symptoms and age, not a single blood test, since hormones swing too much day to day to pin down.

What to do: if you're in your forties with changing periods and any of these symptoms, perimenopause is the likely explanation — and you don't need to wait until periods stop to get help. Tracking your cycle and symptoms gives you and your GP a clearer picture, and lifestyle changes (and HRT where appropriate) work during the transition.