Medically, menopause is the cessation of menstruation and signifies the inability to bear children. It is determined as one year from the last menstrual cycle. Menopause is a natural life-stage transition. Medical events, like surgery or chemotherapy , however, can also produce menopause.
Menopause is a natural transition that will affect every woman. By the year 2020, it is estimated that there will be 62 million American women reaching menopause. Most of these women will spend one-third to one-half of their lives postmenopause.
No changes in life expectancy or general health have affected the age at which menopause occurs. The average age of onset of natural menopause is 51, with a normal range between 48 and 58. There are women who experience it as early as 35 and as late as 60. Eight percent of women stop menstruating before age 40, and 5% continue to have periods until they are near 60. Usually, there is an underlying factor to extremely early or late menopause.
Attempts at defining factors that can predict age of onset have not been successful. It is clear that heredity and smoking seem to be linked to the timing of menopause. A mother's age at menopause may indicate when her daughter will cease menstruation, though this is not a hard- and-fast rule. If a mother entered puberty late and her daughter had her first period at an early age, there may be no correlation. The mother may have experienced poor nutrition as a child or had an hormonal deficiency or some other medical condition to delay puberty.
Smokers enter menopause as much as 1.5 years earlier than non-smokers. Other determinants can be number of pregnancies, body mass, depression, chemical exposure, and exposure to pelvic radiation as a child. Women who have had children, have larger body mass, and who had higher cognitive scores as children may enter menopause later. Conversely, women who never had children, are depressed, were exposed to toxic chemicals, or had pelvic radiation usually have an earlier menopause.
There are four types of menopause. The most prevalent is natural, spontaneous menopause. Premature (spontaneous), surgical, and induced menopause occur because of a medical condition, a surgical procedure, or other outside cause.
Natural (spontaneous) menopause
Most menopause is natural and occurs as part of the aging cycle for women. Technically, it refers to a state in a woman's menstrual cycle which happens a year from the date of her last menstrual period. Indications that the process is starting may occur in a woman's 40's with the lengthening and irregularity of menstrual cycles. The process can take as long as eight years, or may be over in two. Only 10% of women report that menstruation ceases suddenly, with no cycle irregularity prior.
There are four stages that a woman experiences when she experiences natural menopause.
MENSTRUATION. When a woman enters puberty, each month her body releases one of the more than 400,000 eggs that are stored in her ovaries, and the lining of the womb (uterus) thickens in anticipation of receiving a fertilized egg. If the egg is not fertilized, progesterone levels drop and the uterine lining sheds. This is a normal menstrual cycle.
By the time a woman reaches her late 30s or 40s, her ovaries begin to produce less estrogen and progesterone, releasing eggs less often. The gradual decline of estrogen causes a wide variety of changes in tissues that respond to estrogen—including the vagina, vulva, uterus, bladder, urethra, breasts, bones, heart , blood vessels , brain , skin, hair, and mucous membranes.
As the levels of hormones fluctuate, the menstrual cycle begins to change. Some women may have longer periods with heavy flow followed by shorter cycles and hardly any bleeding, beginning as much as two to eight years before menopause. Others will begin to miss periods completely. During this time, a woman also becomes less able to get pregnant (although contraception should be continued until the postmenopausal state is established). This is the stage of premenopause which represents the very beginning of the process. Typically, it begins when a woman is in her mid-to-late forties.
PERIMENOPAUSAL TRANSITION. Perimenopause is the stage most women consider as going through menopause. Here a woman's cycles become very erratic. She may experience more hot flashes and other symptoms. Only about 15% of women report severe symptoms. This stage lasts about four years, the two years prior to the last cycle and the two years following it. For 95% of women, the age of onset ranges from 39 to 51 years. The average age for perimenopause is 47.5 years, with completion at 51.
MENOPAUSE. This is the permanent cessation of menstruation following the loss of ovarian activity. It often is not officially noted until a year with no cycles has passed.
POSTMENOPAUSE. This stage represents the last years of a woman's life. She may well spend a third to half of her life in this stage. During the first years after menopause, a woman may still experience some perimenopausal symptoms. Here, a woman will begin to deal with some of the effects of aging. In 2001, a woman at 50 or 51 may truly be at mid-life, according to the calendar, since many women will live to be a hundred.
Premature (spontaneous) menopause
Premature menopause occurs spontaneously, without any outside interventions or stresses, and affects about 0.3% of women. It is generally due to ovarian failure and occurs before age 40. Because hormonal levels plummet dramatically, these women experience severe vasomotor symptoms that can last as long as 8.5 years. Fertility may end over several months or immediately.
What a woman would normal experience between a two to eight-year period during normal menopause, women with surgical or premature menopause experience immediately and at a very young age. Some of these women are as young as 15. Fertility ends immediately.
Bilateral oophorectomy, or the surgical removal of both ovaries, can be the result of several different procedures. A complete hysterectomy, or the removal of the uterus and the ovaries, results in menopause. It is performed to remove cancerous growths in the ovaries, uterus, or cervix, and may be done in some types of colon cancer surgery. It can also be done to remove non-malignant fibroid tumors in the uterus or to mitigate the effects of endometriosis (although these procedures do not always require the removal of the ovaries). If surgery leaves one or both ovaries, often menopause is avoided. However, in some cases, menopause occurs regardless of whether the ovaries are left intact.
Induced menopause occurs when a woman has been exposed to pelvic radiation or chemotherapy. The drugs in chemotherapy used to combat cancer can seriously damage the ovaries. This condition may be temporary, lasting only a few months or years. Permanent menopause is more likely if a combination of drugs are used or the woman is close to perimenopause. Pelvic radiation therapy usually produces permanent menopause. Other types of radiation therapy, away from the ovaries, may not affect ovarian hormones at all, thus avoiding induced menopause.
Causes and symptoms
The cause of most menopausal symptoms has been attributed in part to low estrogen levels in the body. Increased amounts of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are also involved. If a woman is overweight, she may experience milder symptoms because the fat stored in her body is converted to estrogen when the hormone levels fall. Also, women who endure premenstrual syndrome (PMS) are more apt to report mood swings. This may be due to differences in hormone levels. New research is beginning to tie psychological factors to these symptoms as well. For example, women who are depressed and angry, especially if they are unhappy in their relationships, often report more pronounced symptoms.
Ethnicity may also be a factor in the development of symptoms. Since most of the menopausal research has been conducted on white women, cross-ethnic studies in 2000 were conducted to discover any racial or ethnic variables. The frequency and type of symptoms reported varied widely between ethnic groups. Japanese American and Chinese American women reported fewer symptoms than the other women. African-American women experienced more hot flashes and vaginal dryness. Hispanic women had more vaginal dryness, urine leakage, and heart palpitations. Non-Hispanic white women reported more sleep difficulties.
It is unclear whether cultural or biological factors are involved in these differences. As for causal agents, that may be too early to tell. In any case, the health care team should be aware that ethnic differences in symptom manifestation do exist in menopause.
About 20% of women in the United States experience menopause with few symptoms. All others report a variety of complaints throughout perimenopause; some mild, some severe enough to interfere with work or daily activities.
There are a variety of symptoms a woman may experience in perimenopause:
- changes in the menstrual cycle, resulting in long cycles and missed periods
- hot flashes
- night sweats
- mood swings/irritability
- memory or concentration problems
- vaginal dryness
- heavy bleeding
- hair changes
- heart palpitations
- sexual disinterest
- urinary changes
- weight gain
The clearest indication of menopause is the absence of a period for one year. It is also possible to diagnose menopause by testing hormone levels. One important test measures the levels of follicle-stimulating hormone (FSH), which rise steadily as a woman ages.
Treatment of specific symptoms should be handled as they manifest and are reported.
The standard treatment for menopause has been hormone replacement therapy, primarily with estrogen. Hormone replacement therapy can treat menopausal symptoms by boosting the estrogen levels enough to suppress symptoms while also providing protection against heart disease and osteoporosis , which causes the bones to weaken. Experts disagree on whether HRT increases or decreases the risk of developing breast cancer .
There are two types of hormone treatments: hormone replacement therapy (HRT) and estrogen replacement therapy (ERT). HRT is the administration of estrogen and progesterone; ERT is the administration of estrogen alone. Only women who have had a hysterectomy (removal of the uterus) can take estrogen alone, since taking this "unopposed" estrogen can cause uterine cancer. The combination of progesterone and estrogen in HRT eliminates the risk of uterine cancer.
Most physicians do not recommend HRT until a woman's periods have stopped completely for one year. This is because women in early menopause who still have an occasional period are still producing estrogen; HRT would then provide far too much estrogen. One way of determining if HRT may be necessary is to measure FSH levels yearly beginning at age 50. When these levels are at or greater than 20 U/l, a postmenopausal hormone program may be recommended.
Many doctors believe that every woman (except those with certain cancers) should take hormones as they approach menopause because of the protection against heart disease, osteoporosis, and uterine cancer and the relatively low risk of breast cancer. Heart disease and osteoporosis are two of the leading causes of disability and death among post-menopausal women. Research in 2000 and 2001 has been challenging the effectiveness of estrogen in preventing heart disease, as well as colorectal cancer and Alzheimer's disease . No substantial study has proven that estrogen is a sound preventative.
Women are poor candidates for hormone replacement therapy if they:
- have ever had breast or endometrial cancer
- have a close relative (mother, sister, grandmother) who died of breast cancer or have two relatives who got breast cancer before age 40
- have had endometrial cancer
- have had gallbladder or liver disease
- have blood clots or phlebitis
Some women with liver or gall bladder disease, or who have clotting problems, may be able to go on HRT if they use a patch to administer the hormones through the skin, bypassing the liver.
Women would make good candidates for HRT if they:
- need to prevent osteoporosis
- have had their ovaries removed
- have significant symptoms
In some women, taking hormones can eliminate hot flashes, vaginal dryness, urinary incontinence (depending on the cause), insomnia, moodiness, memory problems, heavy irregular periods, and concentration problems. But side effects of treatment include bloating, breakthrough bleeding, headaches, vaginal discharge, fluid retention, swollen breasts, and nausea. There can also be an increased risk of gall bladder disease and blood clots. Up to 20% of women who try hormone replacement stop within nine months because of these side effects. However, some side effects can be lessened or prevented by changing the HRT regimen.
The decision should be made by a woman and her doctor after taking into consideration her medical history and situation. Women who choose to take hormones should have an annual mammogram, breast exam, and pelvic exam and should report any unusual vaginal bleeding or spotting (a sign of possible uterine cancer).
A new type of hormone therapy offers some of the same protection against degenerative diseases and bone loss as estrogen, but without the increased risk of breast cancer. This new class of drugs, known as designer estrogens. Under development for nearly a decade, new drugs like Evista are being approved to prevent and treat osteoporosis in 2001. Unfortunately, these drugs have not been effective in combating hot flashes.
The ovaries also produce a small amount of male hormones, which decreases slightly as a woman enters menopause. The vast majority of women never need testosterone replacement, but it can be important if a woman has declining interest in sex. Testosterone can improve the libido, and decrease anxiety and depression; adding testosterone especially helps women who have had hysterectomies. Testosterone also eases breast tenderness and helps prevent bone loss.
However, testosterone does have side effects. Some women experience mild acne and some facial hair growth, but because only small amounts of testosterone are prescribed, most women do not appear to have extreme masculine changes.
Birth control pills
Women who are still having periods but who have annoying menopausal symptoms may take low-dose birth control pills to ease the problems; this treatment has been approved by the FDA for perimenopausal symptoms in women under age 55. HRT is the preferred treatment for menopause, however, because it uses lower doses of estrogen.
Some women also report success in using natural remedies to treat unpleasant symptoms of menopause. Not all women need estrogen, and some women cannot take it. Many doctors do not want to give hormones to women who are still having their periods, however erratically. Indeed, only a third of menopausal women in the United States try HRT and of those who do, eventually half of them drop the therapy. Some are worried about breast cancer, some cannot tolerate the side effects, some do not want to medicate what they consider to be a natural occurrence.
HERBS. Herbs have been used to relieve menopausal symptoms for centuries. In general, most herbs are considered safe, and there is no substantial evidence that herbal products are a major source of toxic reactions. But because herbal products are not regulated in the United States, contamination or accidental overdose is possible. Herbs should be bought from a recognized company or through a qualified herbal practitioner.
Women who choose to take herbs for menopausal symptoms should learn as much as possible about herbal products and work with a qualified practitioner (an herbalist, a specialist in Chinese medicine, or a naturopathic physician). Pregnant women should avoid herbs because of unknown effects on a developing fetus.
The following list of herbs include those that herbalists most often prescribe to treat menstrual complaints:
- Black cohosh (Cimicifuga racemosa): hot flashes and other menstrual complaints.
- Black currant: breast tenderness.
- Chaste tree/chasteberry (Vitex agnus-castus): hot flashes, excessive menstrual bleeding, fibroids, and moodiness.
- Evening primrose oil (Oenothera biennis): mood swings, irritability, and breast tenderness.
- Fennel (Foeniculum vulgare): hot flashes, digestive gas, and bloating.
- Flaxseed (linseed): excessive menstrual bleeding, breast tenderness, and other symptoms, including dry skin and vaginal dryness.
- Gingko (Gingko biloba): memory problems.
- Ginseng (Panax ginseng): hot flashes, fatigue and vaginal thinning.
- Hawthorne (Crataegus laevigata): memory problems, fuzzy thinking.
- Lady's mantle: excessive menstrual bleeding.
- Mexican wild yam (Dioscorea villosa) root: vaginal dryness, hot flashes and general menopause symptoms.
- Motherwort (Leonurus cardiaca): night sweats, hot flashes.
- Oat (Avena sativa) straw: mood swings, anxiety.
- Red clover (Trifolium pratense): hot flashes.
- Sage (Salvia officinalis): mood swings, headaches, night sweats.
- Valerian (Valeriana officinalis): insomnia.
NATURAL ESTROGENS (PHYTOESTROGENS). Research in the efficacy of phytoestrogens, particularly soy products, have been mixed. Some trials suggest that the estrogen compounds in soy products can indeed relieve the severity of hot flashes and lower cholesterol. Others do not.
It is true that people in Asian countries who eat foods high in plant estrogens (especially soy products) have lower rates of breast cancer and report fewer "symptoms" of menopause. While up to 80% of menopausal women in the United States complain of hot flashes, night sweats, and vaginal dryness, only 15% of Japanese women have similar complaints. It is unclear whether this statistic is due to eating phytoestrogens alone or is a factor of genetics or culture.
The study of phytoestrogens is so new that there are not very many recommendations on how much a woman can consume. Herbal practitioners recommend a dose based on a woman's history, body size, lifestyle, diet, and reported symptoms. In one study at Bowman-Gray Medical School in North Carolina, women were able to ease their symptoms by eating a large amount of fruits, vegetables, and whole grains, together with 4 oz (113g) of tofu four times a week.
What concerns some critics of other alternative remedies is that many women think that "natural" or"plant-based" means "harmless." In large doses, phytoestrogens can promote the abnormal growth of cells in the uterine lining. Unopposed estrogen of any type can lead to endometrial cancer, which is why women on conventional estrogen-replacement therapy usually take progesterone (progestin) along with their estrogen. However, a plant-based progesterone product can sometimes be effective alone, without estrogen, in assisting the menopausal woman in rebalancing her hormonal action throughout this transition time.
YOGA. Some women find that yoga (the ancient meditation/exercise developed in India 5,000 years ago) can ease menopausal symptoms. Yoga focuses on helping women unite the mind, body, and spirit to create balance. Studies have found that yoga can reduce stress , improve mood, boost a sluggish metabolism , and slow the heart rate. Specific yoga positions deal with particular problems, such as hot flashes, mood swings, vaginal and urinary problems, and other pains.
EXERCISE. Exercise helps ease hot flashes by lowering the amount of circulating FSH and LH and by raising endorphin levels (which drop when having a hot flash). Even exercising 20 minutes three times a week can significantly reduce hot flashes.
ACUPUNCTURE. This ancient Asian art involves placing very thin needles into different parts of the body to stimulate the system and unblock energy. It is usually painless and has been used for many menopausal symptoms, including insomnia, hot flashes, and irregular periods. Practitioners believe that acupuncture can facilitate the opening of blocked energy channels, allowing the life force energy (chi) to flow freely. Blocked energy, they report, increases the symptoms of menopause.
ACUPRESSURE AND MASSAGE. Therapeutic massage involving acupressure can bring relief from a wide range of menopause symptoms by placing finger pressure at the same meridian points on the body that are used in acupuncture. There are more than 80 different types of massage, including foot reflexology, Shiatsu massage, or Swedish massage, but they are all based on the idea that boosting the circulation of blood and lymph benefits health, and relaxing the body and mind.
Amenorrhea —The cessation of menstrual cycles.
Bilateral oophorectomy —The surgical removal of both ovaries.
Endometrium —The lining of the uterus, which is shed with each menstrual period.
Estrogen —Female hormone produced by the ovaries and released by the follicles as they mature. Responsible for female sexual characteristics, estrogen stimulates and triggers a response from at least 300 tissues, and may help some types of breast cancer to grow. After menopause, the production of the hormone gradually stops.
Estrogen replacement therapy (ERT) —A treatment for menopause in which estrogen is given in pill, patch, or cream form.
Follicle-stimulating hormone (FSH) —The pituitary hormone that stimulates the ovary to mature egg capsules (follicles). It is linked with rising estrogen production throughout the cycle. An elevated FSH (above 40) indicates menopause.
Hormone —A chemical messenger secreted by a gland that is released into the blood, and that travels to distant cells where it exerts an effect.
Hormone replacement therapy (HRT) —The use of estrogen and progesterone to replace hormones that the ovary no longer supplies.
Hot flash —A wave of heat that is one of the most common perimenopausal symptoms, triggered by the hypothalamus' response to estrogen withdrawal.
Hysterectomy —Surgical removal of the uterus.
Ovary —One of the two almond-shaped glands in the female reproductive system responsible for producing eggs and the hormones estrogen and progesterone.
Ovulation —The monthly release of an egg from the ovary.
Pituitary gland —The "master gland" at the base of the brain that secretes a number of hormones responsible for growth, reproduction, and other activities. Pituitary hormones stimulate the ovaries to release estrogen and progesterone.
Progesterone —The hormone that is produced by the ovary after ovulation to prepare the uterine lining for a fertilized egg.
Testosterone —Male hormone produced by the testes and (in small amounts) in the ovaries. Testosterone is responsible for some masculine secondary sex characteristics such as growth of body hair and deepening voice.
Uterus —The female reproductive organ that contains and nourishes a fetus from implantation until birth. Also known as the womb.
Vagina —The tube-like passage from the vulva (a woman's external genital structures) to the cervix (the portion of the uterus that projects into the vagina).
BIOFEEDBACK. Some women have been able to control hot flashes through biofeedback, a painless technique that helps a person train her mind to control her body. A biofeedback machine provides information about body processes (such as heart rate) as the woman relaxes her body. Using this technique, it is possible to control the body's temperature, heart rate, and breathing.
Menopause is a natural condition of aging. Some women have no problems at all with menopause, while others notice significant unpleasant symptoms. A wide array of treatments, from natural products to hormone replacement, mean that no woman needs to suffer through this time of her life.
Health care team roles
Physicians, nurses, physician assistants, and alternative/complimentary health care practitioners assume important roles in a woman's successful transition into postmenopause. Since new research in menopause treatment is occurring every year, it will be the health care team's obligation to provide the woman with accurate options that are specific to her individual case. Referrals for counseling and other psychological services may be necessary if depression or anxiety about aging is a problem. Since the symptoms of perimenopause are not life-threatening, the health care team may be more willing to suggest alternative methods like herbal remedies, yoga, and acupressure, as well as lifestyle changes like exercise and a healthy diet. The goal of the health care team should be to normalize this transition as much as possible and not stigmatize it as a medical condition.
Menopause is a natural part of the aging process and not a disease that needs to be prevented. A variety of treatments are available to treat uncomfortable perimenopausal symptoms. Hormone replacement therapy is often used to combat serious symptoms and prevent a number of degenerative diseases such as heart disease and osteoporosis.
Corio, Laura E., and Linda G. Kahn. The Change Before the Change: Everything You Need to Know to Stay Healthy in the Decade before Menopause. New York: Bantam Books, 2000.
Moore, Michele. The Only Menopause Guide You'll Need. Baltimore: John Hopkins University Press, 2000.
Posner, Trisha. This Is Not Your Mother's Menopause: One Woman's Natural Journey Through Change. New York: Villard, 2000.
"Alternatives for the Menopause." Chemist & Druggist (January 27, 2001): 23.
Minkin, Mary Jane, and Toby Hanlon. "Answers to Your Top Five Menopause Questions." Prevention 53, no. 1 (January 2001): 89.
Morris, Kelly. "U.S. Survey Finds that Race Matters." The Lancet 356, no. 9233 (September 9, 2000): 916.
Speroff, Leon. "Management of the Perimenopausal Transition." Contemporary OB/GYN 45, no. 10 (October 2000): 14.
American Menopause Foundation, Inc., Empire State Bldg., 350 Fifth Ave., Ste. 2822, New York, NY 10118. (212) 714-2398.
Federation of Feminist Women's Health Centers. 633 East 11th Ave., Eugene, OR 97401. (503) 344-0966.
Hysterectomy Educational Resources and Services Foundation (HERS). 422 Bryn Mawr Ave., Bala Cynwyd, PA 19004.(215) 667-7757.
National Women's Health Network. 1325 G St. NW, Washington, DC 20005. (202) 347-1140.
North American Menopause Society. PO Box 94527, Cleveland, OH 44101. (440) 442-7550, (800) 774-5342. <http:www.menopause.org/>.
Resources for Midlife and Older Women. 226 E. 70 St., Ste. 1C, New York, NY 10021. (212) 439-1913.
Menopause Online. <http://www.menopauseonline.com/links.htm>.
Meno Times. <http://www.aimnet.com/~hyperion/meno/menotimes.index.html>.
Power Surge Reading Room. <http://members.aol.com/dearest/news.htm>.
Women's Health. <http://women.shn.net/index.html>.
Women's Health Initiative. <http://www.nih.gov/od/odp/whi>.
Janie F. Franz