The menopause is a natural part of the ageing process for women that usually occurs at some point between the ages of 45 and 55 years. It happens because the ovaries lose their responsiveness to follicle-stimulating hormone (FSH) and luteinising hormone (LH) and so produce less oestrogen. This disrupts the menstrual cycle, meaning that eggs are not released as regularly as they used to be and eventually ovulation ceases altogether. At the point at which a woman has not had a period for a year, she is regarded as having experienced the menopause. At this stage, the risk of certain diseases goes up due to a combination of reduced oestrogen and natural ageing, including osteoporosis, cardiovascular disease, stroke and changes to the bladder and vagina.

The time over which the hormonal changes occur is known as the perimenopause. As well as noticing that periods are becoming more irregular, women may experience a whole range of symptoms including hot flushes; night sweats; vaginal dryness, which can cause discomfort during sex; difficulty sleeping; low mood; anxiety; reduced sex drive and difficulty concentrating and remembering things. The duration and severity of symptoms vary hugely, but women who go through a sudden menopause – perhaps because it has been triggered by treatment for cancer or because of surgery to remove the ovaries because of an underlying medical condition – tend to suffer more. Regardless, around 80 per cent of women will experience menopausal symptoms of some kind, and this can have a significant impact on everyday life.