Menopause may pass with no signs other than cessation of menstruation, or it may be accompanied by menstrual changes (heavy or erratic periods), night sweats, hot flashes, and vaginal dryness. There is some debate as to whether emotional symptoms and "mood swings" are any more common during menopause than at any other age. Lower levels of estrogen following menopause may be accompanied by a variety of physical changes. For example, the risk of osteoporosis, in which the bones lose elasticity and become brittle, increases. In addition, levels of high-density lipoproteins (HDLs) decrease as low-density lipoproteins (LDLs) increase, arteries lose elasticity, and more body weight is redistributed to the waist area—all heightening the risk of heart disease. Other possible estrogen-related changes include stress incontinence due to loss of muscle tone in the pelvis, loss of elasticity in the skin, and hair thinning.
Estrogen replacement therapy (ERT) is a controversial treatment introduced in the 1970s for bodily changes that occur in menopause; beginning in the 1980s progestins were added to reduce the risk of uterine cancer. Although ERT eases hot flashes and other physical changes and appears to decrease the risk of osteoporosis, it has been linked to increases in breast cancer, heart disease, and stroke.
Other approaches to dealing with the physical changes include exercise to help circulation, increase bone density and HDL levels, and lower stress; lubricants for vaginal dryness; avoidance of smoking and excess alcohol; and dietary changes limiting protein and fat and increasing fiber and calcium. Natural remedies such as vitamins E and B6 or ginseng and other foods that contain or mimic estrogen are sometimes recommended, but research as to their efficacy has been limited.
See also uterus.
See publications of the National Institute of Child Health and Human Development; J. E. Huston and L. D. Lanka, Perimenopause: Changes in a Woman's Health after 35 (1997); Boston Women's Health Book Collective, Our Bodies, Ourselves for the New Century (1998).
Final cessation of menstruation, ending female fertility. It usually begins between ages 45 and 55. A gradual decline in function of the ovaries reduces estrogen production. Ovulation becomes irregular and gradually ceases. The length of the menstrual cycle and periods may vary; flow may lessen or increase. Adjustment of the endocrine system to estrogen reduction causes hot flashes, often at night, with a warm sensation, flushing, and sweating; other symptoms, such as irritability and headaches, may be related more to reactions to aging. Removal or destruction of the ovaries to treat disease causes artificial menopause, with similar but more sudden effects. Changes in hormone balance usually cause no physical or mental disturbances. However, the protective effect of estrogen against osteoporosis and atherosclerosis is lost, and risks of fracture and coronary heart disease increase.
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The word was first applied to humans, and because of this it literally means the cessation of monthly cycles or menstrual cycles, from the Greek roots meno (month) and pausis (a halt). However, the word is not only applied to humans, and menopause is the permanent stopping of female reproductive cycles of various lengths and kinds; menopause is indeed present in a number of mammal species other than humans.
In adult human females who still have a uterus, and who are not pregnant or lactating, postmenopause is identified by a permanent (at least one year's) absence of monthly periods or menstruation. In women without a uterus, menopause or postmenopause is identified by a very high FSH level.
In human females, menopause usually happens more or less in midlife, signaling the end of the fertile phase of a woman's life. Menopause is perhaps most easily understood as the opposite process to menarche, the start of the monthly periods. However, menopause in women cannot satisfactorily be defined simply as the permanent "stopping of the monthly periods", because in reality what is happening to the uterus is quite secondary to the process; it is what is happening to the ovaries that is the crucial factor.
For medical reasons, the uterus must sometimes be surgically removed (hysterectomy) in a younger woman; her periods will cease permanently, and the woman will technically be infertile, but as long as at least one of her ovaries is still functioning, the woman will not have reached menopause, because even without the uterus, ovulation and the release of the sequence of reproductive hormones will continue to cycle on until menopause is reached. But in circumstances where a woman's ovaries are removed (oophorectomy), even if the uterus were to be left intact, the woman will immediately be in "surgical menopause".
Thus menopause is based on the shutting down (or surgical removal of) the ovaries, which are a part of the body's endocrine system of hormone production, in this case the hormones which make reproduction possible and influence sexual behavior. The process of the ovaries shutting down is a phenomenon which involves the entire cascade of a woman's reproductive functioning, from brain to skin, and this major physiological event usually has some effect on almost every aspect of a woman's body and life.
The menopause transition, and post-menopause itself, is a natural life change, not a disease state or a disorder. The transition itself can be challenging for a number of women, but for others it is not difficult.
After a number of years of erratic functioning, the ovaries almost completely stop producing progesterone and two out of the three estrogen hormones: estradiol and estriol. Estrone is one estrogen which is still produced in reasonable amounts in post-menopausal women. Testosterone levels decrease; however, a decrease in testosterone levels begins gradually in young adulthood. Testosterone levels are thought not to drop significantly during the menopause transition because the stroma of the postmenopausal ovary and the adrenal gland still continue to secrete small amounts of testosterone, even during post-menopause.
Menopause is the end of the reproductive years rather than the beginning, and thus it is the opposite of menarche, nonetheless it can usefully be compared with that event: the menopause transition years are in many ways similar to puberty in reverse, and the psychological and social challenges of the Change are also somewhat similar to those encountered during adolescence.
Rarely the ovaries stop working at a very early age, anywhere from the age of puberty to age 40, and this is known as premature ovarian failure (POF), also commonly referred to as "premature menopause". 1% of women experience POF, and it is not considered to be due to the normal effects of aging. Some known causes of premature menopause include autoimmune disorders, thyroid disease, diabetes mellitus, chemotherapy, eating disorders, and radiotherapy. However, in the majority of spontaneous cases of premature menopause, the cause is unknown.
Premature menopause is diagnosed or confirmed by measuring the levels of follicle stimulating hormone (FSH) and luteinizing hormone (LH); the levels of these hormones will be abnormally high 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.
In the ancient past, menarche and menopause were considered to mark the transitions from "maiden" to "matron", and from "matron" to "crone", (in other words, from little girl to reproductive woman and then to older woman.) Although the significance of the changes that surround menarche is still fairly well recognized, in countries such as the USA, the social and psychological ramifications of the menopause transition are frequently ignored or underestimated.
In common everyday parlance however, the word "menopause" is usually not used to refer to one day, but to the whole of the menopause transition years. This span of time is also referred to as the change of life, the change, or the climacteric and more recently is known as "perimenopause", (literally meaning "around menopause").
The word menopause is also often used in popular parlance to mean all the years of postmenopause.
In the perimenopause years, many women find that they undergo some bodily effects resulting from hormonal fluctuation, such as hot flashes. When these effects are strong, women may sometimes seek medical advice. Mood changes, insomnia, fatigue, memory problems, and other complaints are sometimes considered to be unrelated to the hormonal fluctuations, but not enough research has been done to properly clarify any of these issues. However, for cultural reasons, even women who are free of any troublesome physical effects of perimenopause, may nonetheless find themselves moving through a psychosocial transition.
One piece of recent research appears to show that melatonin supplementation in perimenopausal women can produce 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.
Perimenopause is a relatively new term. The use of it was criticized by some cultural commentators , because they feel that it extends the negative connotations of menopause over many more years of a woman's life.
A woman who still has her uterus can be declared to be in postmenopause once she has gone 12 full months with no flow at all, not even any spotting. When she reaches that point, she is one year into postmenopause.
The reason for this delay in declaring a woman postmenopausal is because periods are usually extremely erratic at this time of life, and therefore a reasonably long stretch of time is necessary to be sure that the cycling has actually ceased completely.
At this point a woman is considered infertile, and no longer needs to factor in the possibility of becoming pregnant. However the possibility of becoming pregnant has usually been very low (but not zero) for a number of years before this point is reached.
In women who have no uterus, and therefore have no periods, post-menopause can be determined by a blood test which can reveal the very high levels of Follicle Stimulating Hormone (FSH) that are typical of post-menopausal women.
A woman's reproductive hormone levels continue to drop and fluctuate for some time into post-menopause, so any hormone withdrawal symptoms that a woman may be experiencing do not necessarily stop right away, but may take quite some time, even several years, to disappear completely.
Any period-like flow that might occur during postmenopause, even just spotting, must be reported to a doctor. The cause may in fact be minor, but the possibility of endometrial cancer must be checked for and eliminated.
However, menopause can be surgically induced by bilateral salpingo-oophorectomy (removal of both ovaries and both fallopian tubes), which is often, but not always, done in conjunction with hysterectomy. Cessation of menses as a result of removal of the ovaries is called "surgical menopause". The sudden and complete drop in reproductive hormone levels usually produces extreme hormone-withdrawal symptoms such as hot flashes, etc.
As mentioned above, removal of the uterus, hysterectomy, does not itself cause menopause, although pelvic surgery can often precipitate a somewhat earlier menopause, perhaps because of a compromised blood supply to the ovaries. Removing the ovaries however, causes an immediate and powerful "surgical menopause", even if the uterus is left intact.
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.
It is however worth pointing out, that not every woman experiences bothersome levels of these effects, and even in those women who do experience strong effects, the range of effects and the degree to which they appear is very variable from person to person.
Those effects that are due to low estrogen levels (for example vaginal atrophy and skin drying) remain present even after the menopause transition years are over, however, many of the effects that are caused by the extreme fluctuations in hormone levels (for example hot flashes and mood changes) usually disappear or improve significantly once the perimenopause transition time has been completed.
Both users and non-users of hormone replacement therapy identify lack of energy as the most frequent and distressing effect Other effects can include vasomotor symptoms such as hot flashes and palpitations, psychological effects such as depression, anxiety, irritability, mood swings, memory problems and lack of concentration, and atrophic effects such as vaginal dryness and urgency of urination.
The average woman also has increasingly erratic menstrual periods, due to skipped ovulations. Typically the timing of the flow becomes unpredictable. In addition the duration of the flow may be considerably shorter or longer than normal, and the flow itself may be significantly heavier or lighter than was previously the case, including sometimes long episodes of spotting. Early in the process it is not uncommon to have some 2-week cycles. Further into the process it is common to skip periods for months at a time, and these skipped periods may be followed by a heavier period. The number of skipped periods in a row often increases as the time of last period approaches. As mentioned above, when a woman of menopausal age has not had a period or any spotting for 12 months, at that point she is considered to be one year into post-menopause. However, a period after 6 months of no flow at all is sometimes considered worthy of investigation by a doctor.
All the various possible perimenopause effects are caused by an overall drop, as well as dramatic but erratic fluctuations, in the absolute levels and relative levels of estrogens and progesterone. Some of the effects, such as formication, may be associated directly with hormone withdrawal.
Urogenital atrophy, also known as vaginal atrophy, (main article: Atrophic vaginitis)
Skin, soft tissue
One cohort study found that menopause was associated with hot flashes; joint pain and muscle pain; and depressed mood. In the same study, it appeared that menopause was not associated with poor sleep, decreased libido, and vaginal dryness.
As a result, a woman who happens to undergo a strong perimenopause with a large number of different effects, may become confused and anxious, fearing that something abnormal is happening to her. There is a strong need for more information and more education on this subject.
There are several types of hormone therapies, with various possible side effects. Hormone replacement therapy or HRT, known in Britain as Hormone Therapy or HT, and the SSRIs appear to provide the most reliable pharmaceutical relief. However, adverse effects of one kind of HRT (equine estrogen combined with a synthetic progestin) are now well documented. See the section below on "Adverse effects of conjugated equine estrogens".
In addition to relief from hot flashes, hormone therapy remains an effective treatment for osteoporosis.
A woman and her doctor should carefully review her situation, her complaints and her relative risk before determining whether the benefits of HT/HRT or other therapies outweigh the risks. Until more becomes understood about the possible risks, women who elect to use hormone replacement therapy are generally well advised to take the lowest effective dose of hormones for the shortest period possible, and to question their doctors as to whether certain forms might pose fewer dangers of clots or cancer than others.
In HT or HRT, one or more estrogens, usually in combination with progesterone, (and sometimes testosterone) are administered, not only to partially compensate for the body's loss of these hormones, but also in an attempt to keep the levels of these hormones in the body much more consistent than they are naturally in perimenopause.
In those women who have no uterus (usually due to a previous hysterectomy) estrogen alone is a suitable hormone therapy. Women who still have a uterus need to take progesterone in addition to estrogen, in order to ensure that the endometrium, the lining of the uterus, does not build up too much, which would be a risk for cancer of the endometrium.
Conjugated equine estrogens contain estrogen molecules conjugated to hydrophilic side groups (e.g. sulfate) and are produced from the urine of pregnant Equidae (horses) mares. Premarin is the prime example of this, either alone or in Prempro, where it is combined with a synthetic progestin, medroxyprogesterone acetate. However Premarin, and especially Prempro, are associated with serious health risks.
In January 2003, the U.S. FDA required Wyeth to affix a "black box" warning to PremPro, stating:
Estrogens and progestins should not be used for the prevention of cardiovascular disease. The Women’s Health Initiative (WHI) reported increased risks of myocardial infarction, stroke, invasive breast cancer, pulmonary emboli, and deep vein thrombosis in postmenopausal women during 5 years of treatment with conjugated equine estrogens (0.625 mg) combined with medroxyprogesterone acetate (2.5 mg) relative to placebo (see CLINICAL PHARMACOLOGY, Clinical Studies). Other doses of conjugated estrogens and medroxyprogesterone acetate, and other combinations of estrogens and progestins were not studied in the WHI ..."
Women had been advised for many years by numerous doctors and drug company marketing efforts (at least in the USA) that hormone therapy with conjugated equine estrogens after menopause might reduce their risk of heart disease and prevent various aspects of aging. However, a large, randomized, controlled trial (the Women's Health Initiative) found that women undergoing HT or HRT with conjugated equine estrogens (Premarin), whether or not used in combination with a synthetic progestin (Premarin plus Provera, known as Prempro), had an increased risk of breast cancer, heart disease, stroke, and Alzheimer's disease. Although this increase in risk was small overall, it passed the thresholds that had been established by the researchers in advance as sufficient to ethically require stopping the study.
When these results were first reported in 2002, the popular media sensationalized the story and exaggerated the risk, while the manufacturer continued to attempt to minimize the degree of risk. However most news stories failed to mention that the average age of the women in WHI was 62 years old, significantly older than the time when most doctors start patients on HRT, and in fact many years into postmenopause. In order to enroll in the study, patients had to be asymptomatic of hot flashes, so they would not know whether they received the placebo. For these reasons WHI was not representative of generally accepted clinical practice.
The 2002 and 2003 announcements of the Women's Health Initiative of the American National Institute of Health and The Million Women Study of the UK Cancer Research and National Health Service collaboration respectively, that HRT treatment coincides with a increased incidence of breast cancer, heart attacks and strokes, lead to a sharp decline in HRT prescription throughout the world , which was followed by a decrease in breast cancer incidence .
On hearing the news about the WHI study, many women discontinued equine estrogens altogether, with or without their doctor's approval. The number of prescriptions written for Premarin and PremPro in the United States dropped within a year almost to half of their previous level. This sharp drop in usage was followed by large and successively larger drops in new breast cancer diagnoses, at six months, one year, and 18 months after the drop in Premarin and Prempro prescriptions, for a cumulative 15% drop by the end of 2003. However, the apparent meaning of this correlation is called into question by the fact that prescriptions of Prempro and Premarin fell dramatically in Canada as well, but no similarly dramatic drop in Canada's breast cancer rates was observed during the same time period. Studies designed to track the further progression of this trend after 2003 are under way, as well as studies designed to quantify how much of the drop was related to the reduced use of HT/HRT.
The adverse biological effects of xenoestrogens and progestins revealed by studies of Premarin and PremPro do not necessarily generalize to supplementation with human forms of estrogen and progesterone. For example, a pilot study reported in JAMA by Smith, Heckbert, et al. found clinical evidence that oral conjugated equine estrogens caused clotting, but the other estrogen compound tested in the same study, bioidentical esterified estrogens, did not. conjugated equine estrogens were found to be associated with increased venous thrombotic risk. In sharp contrast, the study found that users of esterified estrogen had no increase in venous thrombotic risk.
Due to the controversy about Premarin-based hormone therapy, a number of doctors are now moving patients who request hormone therapy to help them through perimenopause, to bioidentical hormone products.
Estrace is a form of the precursor to estrogen in the human body known as estradiol, which products have produced fewer side effects than conjugated equine estrogens. Prometrium is a bioidentical progesterone which can be used in conjunction with Estrace.
However, all hormone replacement therapies probably do carry some health risks, including high blood pressure, blood clots, and increased risks of breast and uterine cancers. Women who have had a hysterectomy seem to tolerate estrogen-only therapy with fewer risks than apply to mixed-hormone therapy in women who still have a uterus.
The anti-seizure medication gabapentin (Neurontin) seems to be second only to HRT in relieving hot flashes.
In the area of complementary and alternative therapies, acupuncture treatment is promising. There are some studies indicating positive effects, especially on hot flashes but also others showing no positive effects of acupuncture regarding menopause.
There are claims that soy isoflavones are beneficial concerning menopause. However, one study indicated that soy isoflavones did not improve or appreciably affect cognitive functioning in postmenopausal women.
Other remedies which in some studies appear to work well, but in other studies appear to be no better than a placebo include red clover isoflavone extracts and black cohosh. Black cohosh can cause the stimulation of pre-existing breast cancer.