Overview

Menopause occurs as the ovaries stop producing estrogen, causing the reproductive system to gradually shut down. The term menopause comes from the Greek roots 'meno-' (month) and 'pausis' (a pause, a cessation).

Technically, menopause refers to the cessation of menses; whereas the gradual process through which this occurs, which typically takes a year but may last as little as six months or more than five years, is known as climacteric.

Very early symptoms that precede menopause, referred to as perimenopause, typically begin in the late 30s or early 40s. Popular use replaces climacteric with menopause.

The average onset of menopause is 46 years, but some women enter menopause at a younger age, especially if they have had cancer or another serious illness and undergone chemotherapy.

Premature menopause (or premature ovarian failure) is defined as menopause occurring before the age of 40; it occurs in 1% of women. Other causes of premature menopause include autoimmune disorders, thyroid disease, and diabetes mellitus. Premature menopause is diagnosed by measuring the levels of follicle stimulating hormone (FSH) and luteinizing hormone (LH); the levels of these hormones will be higher if menopause has occurred. Rates of premature menopause have been found to be significantly higher in fraternal and identical twins; approximately 5% of twins reach menopause before the age of 40. The reasons for this are not completely understood. Transplants of ovarian tissue between identical twins have been successful in restoring fertility.

Post-menopausal women, especially Caucasian women of European descent, are at increased risk of osteoporosis.

One reason for this risk is the dramatic change in female sex hormone levels that occurs: These hormones play a major role in female skeletal development and changes lead to an acceleration of bone mass loss rate.

Perimenopause

Perimenopause refers to the time preceding menopause, during which the production of hormones such as estrogen and progesterone diminish and become more irregular. During this period, fertility diminishes. Menopause is arbitrarily defined as beginning when a minimum of twelve months without menstruation have passed. Symptoms of perimenopause can begin as early as age 35, although most women become aware of them much later. It can last for a few months or for several years. The duration of perimenopause cannot be predicted in advance.

Recent research has concluded that melatonin supplementation in perimenopausal women produces a highly significant improvement in thyroid function and gonadotropin levels, as well as restoring fertility and menstruation and preventing the depression associated with the menopause.

A natural or physiological menopause is that which occurs as a part of a woman's normal aging process. However, menopause can be surgically induced by bilateral salpingo-oophorectomy (removal of both ovaries and both fallopian tubes), which is often done in conjunction with hysterectomy; the resulting cessation of menses as a result of reproductive organ removal is sometimes called "surgical menopause".

The cessation of menses that is not due to surgical removal of the reproductive organs is the result of the eventual atresia of almost all oocytes in the ovaries. This causes an increase in circulating FSH and LH levels as there are a decreased number of oocytes responding to these hormones and producing estrogen. This decrease in the production of estrogen leads to the post-menopausal symptoms of hot flashes, insomnia, osteoporosis, atherosclerosis, vaginal atrophy and depression.

Cigarette smoking has been found to decrease the age at menopause by as much as one year, and women who have undergone hysterectomy with ovary conservation go through menopause 3.7 years earlier than average. However, premature menopause (before the age of 40) is generally idiopathic.

Symptoms

As the body adapts to the changing levels of natural hormones, vasomotor symptoms such as hot flashes and palpitations, psychological symptoms such as depression, anxiety, irritability, mood swings and lack of concentration, and atrophic symptoms such as vaginal dryness and urgency of urination appear. Together with these symptoms, the woman may also have increasingly erratic menstrual periods.

The clinical features of menopause are caused by lessening amounts of estrogen, progesterone, and testosterone in the woman's body.

* hot flashes, hot flushes, including night sweats

* sleep disturbances

* itching

* dryness

* bleeding

* urinary frequency

* urinary urgency

* urinary incontinence

* osteoporosis

* joint pain, muscle pain

* back pain

* breast atrophy

* skin thinning

* decreased elasticity

* mood disturbance

* irritability

* fatigue

* memory loss

* depression

* decreased libido

* vaginal dryness

* problems reaching orgasm

* dyspareunia

Treatment of symptoms

While menopause is a natural stage of life, some symptoms may be alleviated through medical treatments. Hormone replacement therapy (HRT) provides the best relief, but certain forms appear to pose significant health risks. Some drugs afford limited relief from hot flashes. A woman and her doctor should carefully review her symptoms and relative risk before determining whether the benefits of HRT or other therapies outweigh the risks. Until more becomes known, women who elect to use hormone replacement therapy are generally well advised to take the lowest effective dose of HRT for the shortest period possible and to investigate whether certain forms may pose fewer dangers of clots or cancer than others.

Hormone replacement therapy

In addition to relief from hot flashes, hormone replacement therapy (HRT) remains an effective treatment for osteoporosis. Women had been advised for many years that hormone therapy after menopause might reduce their risk of heart disease and various aspects of aging. However, a large, randomized, controlled trial (the Women's Health Initiative) found that women undergoing HRT with conjugated equine estrogens (Premarin), whether or not used in combination with a progestin (Premarin plus Provera), had a slightly increased risk of breast cancer, heart disease, stroke, and Alzheimer's disease sufficient to justify stopping the study.

After these results were reported in 2002, the number of prescriptions written for Premarin and PremPro in the United States dropped almost in half, as many women discontinued HRT altogether. The sharp drop in prescriptions for Premarin and PremPro following the mid-2002 announcement of their dangers was followed by large and successively greater drops in new breast cancer diagnoses at six months, one year, and 18 months after that announcement, for a cumulative 15% drop by the end of 2003. Surprisingly, no similar drop in Canada's breast cancer rates was observed during the same period, though prescriptions of PremPro and Premarin were reduced in Canada as well. Studies designed to track the further progression of this trend after 2003 are underway, as well as to determine if the drop is related to the reduced use of HRT.

The anti-seizure medication gabapentin (Neurontin) seems to be second only to HRT in relieving hot flashes.[citation needed]

Antidepressants such as paroxetine (Paxil), Fluoxetine hydrochloride (Prozac), and Venlafaxine hydrochloride (Effexor) have been used with some success in the treatment of hot flashes, improving sleep, mood, and quality of life. Of these, Paxil has been the most studied and may provide the most consistent relief[citation needed]. There is a theoretical reason why SSRI antidepressants might help with memory problems-- they increase circulating levels of the neurotransmitter serotonin in the brain and restore hippocampal function. Prozac has been repackaged as Serafem and is approved and prescribed for premenstrual dysphoric disorder (PMDD), a mood disorder often exacerbated during perimenopause and early menopause. PMDD has been found by PET scans to be accompanied by a sharp drop in serotonin in the brain and to respond quickly and powerfully to SSRIs.

About as effective as antidepressants for hot flashes, but without the other mind and mood benefits of antidepressants, are blood pressure medicines including clonidine (Catapres). These drugs may merit special consideration by women suffering both from high blood pressure and hot flashes.

Complementary and alternative therapies

It should be noted that medical non-hormone treatments provide less than complete relief, and each has side effects.

In the area of complementary and alternative therapies, acupuncture treatment is promising[1]. Some studies have noted a slight benefit from soy isoflavones. Other remedies that have proven no better than a placebo at treating hot flashes and other menopause symptoms include red clover isoflavone extracts and black cohosh. Black cohosh has potentially serious side-effects such as the stimulation of breast cancer, therefore prolonged administration is not recommended in any case.

Obvious measures, such as drinking cold liquids and removing excess clothing layers when hot flashes strike, and avoiding hot flash triggers such as spicy foods, may supplement or supplant the use of medications for some women.