Menopause is when you stop having periods, which usually happens between the ages of 45 and 55. For a small number of women menopause occurs earlier. If it happens before you are 40 it's called premature menopause (or premature ovarian insufficiency).
Menopause happens when your ovaries stop producing a hormone called oestrogen and no longer release eggs. For some time before this – it could be for a few months or for several years – your periods may become less regular as your oestrogen levels fall. This is called perimenopause.
During perimenopause you might have symptoms such as hot flushes, night sweats, joint and muscle pain, vaginal dryness, mood changes and a lack of interest in sex.
Menopause affects every woman differently. You may have no symptoms at all, or they might be brief and short‑lived. For some women they are severe and distressing.
You can still get menopause symptoms if you have had a hysterectomy (an operation to remove your womb).
Other natural changes as you age can be intensified by menopause. For example, you may lose some muscle strength and have a higher risk of conditions such as osteoporosis and heart disease.