Recognising the menopause

The menopause occurs when a woman stops menstruating permanently due to the loss of ovarian follicular activity and is diagnosed after a woman has had 12 months without periods (amenorrhoea), which typically occurs between 45-55 years of age. The average age of menopause diagnosis in the UK is 51 years, although this varies by ethnicity.

The menopause is preceded by the peri-menopause when the ovaries gradually stop functioning, oestrogen and progesterone levels fall, and women experience altered and irregular menstrual cycles. Some may start to experience these symptoms from their late 30s onwards.

Around one in 10 women have an early menopause between 40-45 years of age. Menopause before the age of 40 years is categorised as premature ovarian insufficiency and occurs in around 4 per cent of women. If early or premature menopause is suspected, referral to a GP is necessary as investigation and HRT is usually indicated.

Although the menopause is usually a natural event, it is important not to forget women who have had surgical removal of the ovaries, usually occurring at the time of a hysterectomy. It is estimated that 20 per cent of women in the UK have had a hysterectomy, most commonly between the age of 40 and 50 years. Although the ovaries may be preserved, the menopause in these women often occurs earlier than normal.

Sometimes chemotherapy or radiotherapy treatment for cancer can cause ovarian failure. Sudden cessation of ovarian function due to surgery or treatment can lead to severe menopausal symptoms and HRT is often indicated as a result.