Menopause occurs when the ovaries have few remaining eggs and can no longer produce oestrogen and progesterone. Typically, periods become less frequent over a few months or years and then stop completely. For some women, periods come to a sudden rather than gradual stop.
For most women, the menopause is a natural part of getting older. Some women reach menopause before they’re 45, which is called early menopause. Before the age of 40, it’s known as premature menopause. Late menopause is possible but 80% of women will have stopped having periods by the age of 54.
Some treatments, surgeries and conditions can bring about the menopause, such as:
chemotherapy or radiotherapy
oophorectomy – removal of the ovaries (often at the time of a hysterectomy)
underlying conditions for example genetic abnormalities and Addison’s disease
anti-oestrogen hormone therapy
Reaching menopause technically means you’ve had no consecutive periods for 12 months. But menopausal symptoms include anything that you may experience before your periods start to change, during the time your hormone balance starts to affect the pattern of your periods (perimenopause), and the postmenopausal stage – when your periods have stopped for more than a year.