What is menopause?

Menopause is defined as the state of an absence of menstrual periods for 12 months. The menopausal transition starts with varying menstrual cycle length and ends with the final menstrual period. Perimenopause means "the time around menopause" and is often used to refer to the menopausal transitional period. It is not officially a medical term, but is sometimes used to explain certain aspects of the menopause transition in lay terms. Postmenopause is the entire period of time that comes after the last menstrual period.
Menopause is the time in a woman's life when the function of the ovaries ceases. The ovary (female gonad), is one of a pair of reproductive glands in women. They are located in the pelvis, one on each side of the uterus. Each ovary is about the size and shape of an almond. The ovaries produce eggs (ova) and female hormones such as estrogen. During each monthly menstrual cycle, an egg is released from one ovary. The egg travels from the ovary through a Fallopian tube to the uterus.
The ovaries are the main source of female hormones, which control the development of female body characteristics such as the breasts, body shape, and body hair. The hormones also regulate the menstrual cycle and pregnancy. Estrogens also protect the bone. Therefore, a woman can develop osteoporosis (thinning of bone) later in life when her ovaries do not produce adequate estrogen.
Perimenopause is different for each woman. Scientists are still trying to identify all the factors that initiate and influence this transition period.

At what age does a woman typically reach menopause?

The average age of menopause is 51 years old. But there is no way to predict when an individual woman will enter menopause. The age at which a woman starts having menstrual periods is also not related to the age of menopause onset. Most women reach menopause between the ages of 45 and 55, but menopause may occur as earlier as the 30s or 40s or may not occur until a woman reaches her 60s. As a rough "rule of thumb," women tend to undergo menopause at an age similar to that of their mothers.
Perimenopause, often accompanied by irregularities in the menstrual cycle along with the typical symptoms of early menopause, can begin up to 10 years prior to the last menstrual period.

Menopause

Menopause is a term used to describe the permanent cessation of the primary functions of the human ovaries: the ripening and release of ova and the release of hormones that cause both the creation of the uterine lining and the subsequent shedding of the uterine lining (a.k.a. the menses). Menopause typically (but not always) occurs in women in midlife, during their late 40s or early 50s, and signals the end of the fertile phase of a woman's life.
The transition from reproductive to non-reproductive is the result of a major reduction in female hormonal production by the ovaries. This transition is normally not sudden or abrupt, tends to occur over a period of years, and is a natural consequence of aging. However, for some women, the accompanying signs and effects that can occur during the menopause transition years can significantly disrupt their daily activities and their sense of well-being. In addition, women who have some sort of functional disorder affecting the reproductive system (i.e. endometriosis, polycystic ovary syndrome, cancer of the reproductive organs) can go into menopause at a younger age than the normal timeframe; the functional disorders often significantly speed up the menopausal process and create more significant health problems, both physical and emotional, for the affected woman.
The word "menopause" literally means the "end of monthly cycles" from the Greek word pausis (cessation) and the root men- (month), because the word "menopause" was created to describe this change in human females, where the end of fertility is traditionally indicated by the permanent stopping of monthly menstruation or menses. However, menopause also exists in some other animals, many of which do not have monthly menstruation^[1]; in this case, the term is synonymous with "end of fertility".
The date of menopause in human females is formally medically defined as the time of the last menstrual period (or menstrual flow of any amount, however small), in those women who have not had a hysterectomy. Women who have their uterus removed but retain their ovaries do not immediately go into menopause, even though their periods cease. Adult women who have their ovaries removed however, go immediately into surgical menopause, no matter how young they are.
Menopause is an unavoidable change that every woman will experience, assuming she reaches middle age and beyond. It is helpful if women are able to learn what to expect and what options are available to assist the transition, if that becomes necessary. Menopause has a wide starting range, but can usually be expected in the age range of 42–58 (Bucher, et al. 1930). An early menopause can be related to cigarette smoking, higher body mass index, racial/ethnic factors, illnesses, chemotherapy, radiation and the surgical removal of the uterus and/or both ovaries (Bucher, et al. 1930).
Menopause can be officially declared (in an adult woman who is not pregnant, is not lactating, and who has an intact uterus) when there has been amenorrhea (absence of any menstruation) for one complete year. However, there are many signs and effects that lead up to this point, many of which may extend well beyond it too. These include: irregular menses, vasomotor instability (hot flashes and night sweats), atrophy of genitourinary tissue, increased stress, breast tenderness, vaginal dryness, forgetfulness, mood changes, and in certain cases osteoporosis and/or heart disease (Bucher, et al., 1931). These effects are related to the hormonal changes a woman’s body is going through, and they affect each woman to a different extent. The only sign or effect that all women universally have in common is that by the end of the menopause transition every woman will have a complete cessation of menses.