All women go through the menopause, a natural menopause is said to have happened one year after your last natural period. The average age of women going through the menopause is 51-years old. By the age of 54, 80% of women have stopped having periods. Natural menopause usually happens gradually, with oestrogen levels fluctuating in perimenopause, periods may become irregular and then gradually stop.
Early menopause: this is when the menopause occurs younger than 45 years old.
Premature menopause, or premature ovarian insufficiency (POI): this is when the menopause occurs younger than 40, and affects 1 in 100 women. Menopause under the age of 30 affects one in 1000 women.
Surgical menopause: this is when menopause occurs following an operation to remove your ovaries. This procedure may occur as part of cancer or endometriosis treatment; in order to reduce the risk of developing cancer (in those who carry the BRCA gene mutations, for example; as a last resort in people who suffer with premenstrual dysmorphic disorder (PMDD), a severe form of premenstrual syndrome (PMS). This is different from natural menopause, as oestrogen production, which was being produced by the ovaries, is suddenly withdrawn.
Postmenopause is the time following one year after your last natural period.