The term menopause is defined as the final bleed a woman will have. It is an entirely natural event and every woman will experience it, if she lives long enough. The word "menopause" is often used to define the period of time that leads up to a woman's' final period, although this is strictly a period of time called the "peri-menopause". The final menstrual period takes place, usually between the ages of 45 and 55, although it can be earlier or later, the peri-menopause can begin as early as ten years before the final bleed and is caused when the two ovarian hormones, estrogen and progesterone are no longer stimulating the endometrium to prepare for eggs.

For women who have had a hysterectomy and you have your ovaries removed at the time of your hysterectomy then you will have an immediate menopause, regardless of your age. If you have a hysterectomy and your ovaries are left intact then you have up to a 50% chance of your ovaries failing within five years of your hysterectomy, this may be because the blood supply to the uterus has been cut off . Radiation treatment following hysterectomy for cancer may also cause the ovaries to fail prematurely. Menopause that occurs before the age of 45, regardless of the cause, is called premature menopause

Premature menopause can be the result of genetics, autoimmune disorders or medical procedures such as Premature ovarian failure. Normally, the ovaries produce both estrogen and testosterone. Changes in the levels of these two hormones occur when the ovaries, for unknown reasons, prematurely stop producing eggs. When this happens before the age of 40, it is considered to be premature ovarian failure. Unlike premature menopause, premature ovarian failure is not always permanent.

All women going through menopause will experience hot flushes, a sudden feeling of warmth that spreads over the upper body that is often accompanied by blushing and some sweating. The severity of this symptom varies from mild in most women to severe in others. Other common symptoms include:

Not all women get all of these symptoms. In fact, less than 2% of women get symptoms severe enough to interfere with daily activities.