Menopause is the time when a womans menstrual cycle permanently stops, and she can no longer get pregnant. It is a normal part of a womans life and is sometimes called "the change of life". Menopause does not happen all at once, and the transition to menopause, called perimenopause, can last between two and eight years before periods stop permanently. For most women, this transition lasts about four years, and they may experience menopause symptoms and irregular periods during this time.

The average age for menopause in the United States is 51, but the range for women is usually between 45 and 58. One way to tell when you might go through menopause is the age your mother went through it. However, menopause can happen earlier due to a medical condition, medication, drug treatment, or surgery such as the removal of the ovaries.

It is important to note that women can still get pregnant during perimenopause, even if their periods are irregular. Women who are experiencing irregular periods and do not want to get pregnant should continue using birth control until they have gone a full year without a period.

In summary, the age at which women stop having periods varies, but the average age is 51 in the United States. The transition to menopause, called perimenopause, can last between two and eight years before periods stop permanently, and women can still get pregnant during this time.