What is the definition of menopause?

Menopause is defined as the cessation of menstrual periods for 12 consecutive months. This definition reflects the natural biological process marking the end of a woman's reproductive years, as the ovaries cease to produce hormones like estrogen and progesterone. The 12-month timeframe is crucial because it provides a clear and definitive marker that distinguishes menopause from other potential causes of amenorrhea, such as pregnancy or hormonal imbalances.

The onset of menopause typically occurs in women during their late 40s to early 50s, although the exact timing can vary for each individual. Once menopause is confirmed, women can often notice a range of physiological changes, including hot flashes, night sweats, and other symptoms related to decreased hormone levels.

The other options presented do not accurately capture the essence of menopause. Menstrual bleeding every 21 days does not indicate menopause but rather describes a regular menstrual cycle. A sudden change in hormone levels may happen at various times, such as during perimenopause, but it does not define menopause itself. Lastly, irregular menstrual cycles lasting more than a year can occur before menopause, a phase known as perimenopause, rather than being indicative of menopause itself.