Menopause is known as "the change of life" and scientifically referred to as the climacteric. The term menopause means the cessation of menstruation (“last menstruation”). However, it is commonly used to refer to the period in a woman's life when she passes out of her reproductive years. Menopause usually begins between the ages of 45 and 50 as the ovaries gradually cease to function. The number of follicles in the ovaries decreases. Production of the female sex hormones diminishes. The phase of fertility ends with the last menstruation. The average age of menopause is 52.

Premature menopause happens before the age of 40, whether it is natural or induced.

Premenopause is the time of life between the first period (menarche) in adolescence to the start of perimenopause.

Perimenopause (peri means surrounding) is the time 5-15 years before the natural end of menstruation. Perimenopause typically begins between the ages of 35-and 50. Eight percent of women become menopausal prior to age 40. Perimenopause is the phase before menopause actually takes place, when ovarian hormone production is declining and fluctuating, often causing physical symptoms. Some clinicians maintain that perimenopause can last for five to 15 years, while others refer to perimenopause as a three to four year period just before menopause.

Many premenopausal women experience changes in their menstrual cycle. When estrogen levels begin to drop, the follicular phase of the cycle may be shortened, and this can shorten the total cycle from 28–30 days to 24–26 days, resulting in more frequent periods. On the other hand, some women begin having longer cycles because they are not ovulating as frequently. These changes are different for each woman. This declining/fluctuating estrogen level can produce a host of disturbing symptoms including: hot flashes, increasing vaginal dryness, sleep problems, mood swings, and breast tenderness.

Menopausal is the end of the climateric, and is applied to women who have not had a period for 12 complete months in a row. This is commonly called "complete menopause". If you experience a period before 12 months, you are still perimenopausal, and must begin counting the 12 months again.

Surgical menopause is a term for women who have their ovaries and uterus removed surgically. Please see hysterecomy and oopherctomy for more information.

Please see, "Hysterectomy Hype and Reality" by Dr. Paul Indman.

Please see, "The Significance of Bleeding after the Menopause" by Dr. J. Glenn Bradley.