The Mystery of Sleep: Why a Good Night's Rest Is Vital to a Better, Healthier Life


When Sex Hormone Levels Decrease Menopause and Andropause


THE MYSTERY. Changing hormone levels affect women’s sleep not only during menstruation and pregnancy but during menopause, when the levels of sex hormones drop. This causes a number of symptoms that affect sleep, including hot flashes and night sweats, as well as symptoms of sleep apnea. Changing hormone levels can also affect men being treated with drugs to reduce levels of testosterone for certain cancers and women being treated for breast cancer, and can lead to similar symptoms.

The Case of the Insomniac with Night Sweats

Sitting in front of me was a fidgety, thin, anxious fifty-one-year-old. Her family doctor had referred her to me because she had been complaining of experiencing a great deal of difficulty in both falling asleep and staying asleep. Most nights, after tossing and turning in bed trying to get comfortable, she would drop off but then, frustratingly, would not be able to sleep through the night. Instead, she would find herself waking up several times, often covered in sweat, with the back of her head and her pillow soaked in perspiration. Sometimes she awakened with her heart pounding, which frightened her. As a result of her interrupted nighttime sleep, she would feel exhausted during the day. Her problems sleeping were affecting every aspect of her life.

She could not pinpoint a particular cause for her sleeplessness. She had no special problems at home or at work, nor could she attribute her sleeplessness to problems with her mood.

Her family doctor had suggested sleeping pills, but she did not like taking pills and preferred to find an alternative way of treating her sleep problems.

She was becoming more and more worried about her sleeplessness, which was causing her to lose weight, and her anxiety further exacerbated her difficulties in falling asleep. Only a few conditions commonly cause this constellation of symptoms.


Menopause, the period following the reproductive phase of a woman’s life when her menstrual cycles have ceased and her body no longer produces estrogen, is a transition experienced by all women. Menopause does not usually come on abruptly; rather, menstrual cycles become irregular or more time elapses between periods. The amount of bleeding with each period may vary. Most doctors agree that menopause is established if periods have been absent for a year. Menopause is not a disease; it is a normal physiological state.

The age at which menopause occurs varies. In some women, it may start when they are in their early forties, while for other women it might not begin until they are over fifty. In North America, most women experience the onset of menopause sometime between the ages of forty-eight and fifty-five, with the average age being about fifty-one. Women might start menopause early because their ovaries were surgically removed for medical reasons. Women being treated for breast cancer are much more likely than others to have menopausal symptoms; the symptoms are particularly common in women who have been treated with medications such as tamoxifen, an anti-estrogen that counteracts the effects of the female hormone estrogen on breast cancer cells, or an aromatase inhibitor, which blocks the production of estrogen (there are several that have been approved in the United States by the Food and Drug Administration).

Just as dramatic changes occur in organ systems for women during adolescence when the ovaries start to produce estrogen, the abrupt reduction of estrogen production during perimenopause and menopause also results in a wide variety of effects. The five most disturbing menopausal symptoms are hot flashes, vaginal dryness, night sweats, disrupted sleep, and weight gain. All involve sleep—even the weight gain could lead to sleep apnea. (These symptoms can also affect the sleep and quality of life of the bed partner.) When menopause occurs abruptly—for example, after surgical removal of the ovaries—symptoms can be quite severe. Some women experience relatively few symptoms with menopause.


During menopause, the way a woman’s body regulates its temperature can change, often to her extreme discomfort. The hot flash is one of the most unpleasant symptoms of menopause, and it is experienced by between 80 and 90 percent of perimenopausal and menopausal women. A study published in 2003 showed that women who smoke cigarettes or are obese are twice as likely as nonsmokers of normal weight to have severe hot flashes. When a woman experiences a hot flash, she feels as though her body temperature is increasing. Indeed, it does increase by a small amount, which fools the hypothalamus, the part of the brain that regulates body temperature. Many scientists believe that reduced estrogen levels, especially if they are reduced rapidly, and release of certain hormones from the pituitary gland cause the hypothalamus to respond as if the body is overheated. This in turn activates the mechanisms the body uses to rid itself of excess heat, redirecting blood flow to the skin and causing sweating.

The main mechanism the body uses to get rid of extra heat is a process called vasodilatation (enlargement of the blood vessels). Blood vessels enlarge, and the blood flow to the skin is increased. So even though the woman feels hot, her body is actually losing heat. It is this increase in blood flow that results in the sudden flushing sensation known as a hot flash. Many doctors use the term vasomotor symptoms to describe the features of the hot flash. The episode usually begins with the perception of feeling hot, followed by flushing of the face, which may then spread to elsewhere on the body. Some women say that the flush begins at their chest and then moves up. The average episode is roughly three minutes long and causes extreme discomfort.

Usually women experience hot flashes for 1 to 7 years, but some women experience them for more than 10 years. A 2015 study reported that the average duration varied by race and ethnicity: African American women averaged 10.1 years, Hispanic women 8.9 years, non-Hispanic Caucasian women 6.5 years, Chinese women 5.4 years, and Japanese women 4.8 years. Many women who experience hot flashes have more than ten episodes per day, which can disrupt their home and work lives. Other women have episodes as infrequently as once a month.

When the hot flashes come at night, the woman may experience night sweats that adversely affect her sleep. (They might also interfere with her bed partner’s sleep; as the husband of a perimenopausal woman with hot flashes noted, “At first, I did not realize my wife had a problem at all. I thought that I had a problem. I was waking up feeling really cold in the middle of the night and found, when I checked, that the thermostat was set much lower than normal. After a few nights of this I discovered that my wife had been setting the temperature much lower.”) Recent research has shown that hot flashes do not occur during REM or dreaming sleep; during REM sleep the body no longer controls its temperature, and abnormal temperature regulation is what leads to the hot flashes.

At the end of the hot flash, women often break out into a sweat over the part of the body that had been involved in the flush. When these episodes occur while a woman is asleep, as they frequently do, the profuse sweating may bother her so much that she cannot get comfortable; she might even have to change the bedclothes if the night sweats are too severe. To make matters worse, at the end of the hot flash, the hypothalamus registers that it has cooled the body too much, and so it turns on the mechanisms to increase the body temperature, which can make the woman feel cold and clammy.


Hot flashes are perhaps the best known and most familiar symptom of menopause, but the reduction of estrogen and progesterone can have other effects on a menopausal woman’s body as well. Estrogen is crucially involved in the reproductive system, and when the production of estrogen decreases the walls of the vagina become thinner, while the production of lubricating fluid is also decreased. The resulting dryness in the vagina may make sexual intercourse painful. Another effect of menopause for many women is a dramatic metabolic change. Often this manifests as weight gain, which among other dangers may increase the likelihood of or put a woman at risk for developing sleep apnea.

Besides estrogen, another important sex hormone that decreases with menopause is progesterone, a hormone that is believed to help protect against the development of sleep apnea. The combination of increased weight and decreased progesterone dramatically increases the risk of a woman’s developing sleep apnea. Finally, the loss of estrogen during menopause puts women at increased risk for cardiovascular disease, cancer (uterine, breast, or ovarian), bone fractures, and other conditions. The cancer risk seems to increase if menopause occurs after age fifty-five.

One often overlooked issue is the impact of all the physiological changes that occur during menopause in conjunction with external emotional events such as children leaving home and coping with the needs of aging parents or other family members. Many women may develop a mood disorder, as life changes and fluctuating hormone levels combine to cause emotional ups and downs.

Sleep Problems Related to Menopause

More than a third of women in North America today are perimenopausal or postmenopausal. Of those women, about 40–60 percent have sleep problems. A 2003 study reported that the highest rates of sleep problems were found in women whose menopause was caused by removal of the ovaries (48 percent of women with surgical menopause had sleep problems) and those late in perimenopause (45 percent). The rates of sleep problems during menopause were much lower in Japanese women (28 percent) than in Caucasian women (40 percent).

Women who are menopausal or postmenopausal are more likely to have insomnia than when they were premenopausal. A poll conducted on women’s sleep in 1998 found that 44 percent of women going through menopause and 28 percent of postmenopausal women have hot flashes at night; on average they had hot flashes three nights a week. This is severe enough to cause trouble sleeping or insomnia for an average of five days each month. Not all groups have hot flashes to the same extent. Another research study from 2003 reported the percentages of women between ages forty and fifty-five who had night sweats: African American women, 36 percent; Hispanic women, 25 percent; Caucasian women, 21 percent; women of Chinese descent, 11 percent; women of Japanese descent, 9 percent.

A 2015 research study showed that women during and after menopausal transition might develop serious insomnia, sleeping on average 43.5 minutes fewer a night during menopausal transition than women not complaining of insomnia. These women were more likely to have hot flashes, and the presence of hot flashes predicted the number of times they awakened during the night. About 50 percent of women with insomnia as they approach menopause sleep less than 6 hours a night.

But not all difficulty in sleeping is caused by hot flashes. Menopausal or postmenopausal women are more likely to have to go to the bathroom at night (43 percent) than premenopausal women (34 percent). Twenty percent of menopausal or postmenopausal women use prescription medications to help them sleep, compared to 8 percent of premenopausal women.

Because smoking and obesity increase the likelihood that a woman will have severe hot flashes, menopausal women should try to stop smoking and bring their weight down. These tasks are obviously a challenge. Menopausal or postmenopausal women on hormone replacement drugs are less likely to have hot flashes during sleep. But because of the perceived risks involved with such medication, many women first try to “sweat it out,” not seeking treatment for their hot flashes. The symptoms usually improve with time, as episodes become less frequent and less severe. Women learn what works best for them. Some women dress in layers so that they can remove one or more when a hot flash comes on; others try using lighter bedclothes, sheets, and comforters. Special fabrics such as Sheex, PowerDry, and CoolMax that wick away sweat from the body and help keep athletes dry are now being used for women’s bedclothes. Some women find that taking a drink of cold water when a flash begins can lessen the severity, so they keep a large glass of cold water on their nightstand. If none of these strategies helps, or if other symptoms are present, women should consult a doctor.

Medical Treatment of Sleep Problems Related to Menopause


In a 2015 study, more than 50 percent of menopausal women reported that their doctor did not seem to recognize the importance of menopause or provided inaccurate information, especially about the use of hormonal therapy. What should women expect from a medical consultation?

Postmenopausal women are at an increased risk for various medical conditions such as heart disease, high blood pressure, osteoporosis (bone thinning), and cancer. A woman seeking medical help should expect her doctor to measure her blood pressure and suggest or conduct the following tests: a Pap smear, tests of blood lipids (cholesterol and triglycerides, which if abnormal increase the risk of heart disease), a breast examination, and often a mammogram. Depending on various risk factors, the doctor might also order bone-density tests since osteoporosis is a common problem in postmenopausal women. A doctor might also order measurements of serum follicle stimulating hormone (FSH) and luteinizing hormone (LH) if it is not clear that menopause has begun. The levels of these two hormones, which change during the normal menstrual cycle, remain elevated when menopause has occurred.

The doctor and patient should discuss risks based on the woman’s personal and family medical history. Does the patient have a personal or family history of cancer, stroke, cardiovascular disease, or blood clots in the legs or lungs? The doctor might also order tests to check thyroid status (an overactive thyroid can cause sweating and flushing). All this information can help the patient decide how to deal with her menopausal symptoms.


Until the summer of 2002, it was widely believed by medical scientists and the public that hormone replacement therapy (HRT) effectively helped prevent cardiovascular disease, osteoporosis, and other disorders that appear to be more common in postmenopausal women than in premenopausal women. But research published in July of that year in the Journal of the American Medical Association (JAMA) showed that there might not be an overall health benefit to using HRT; there might instead be a greater health risk. The research showed a small (but statistically significant) increase in breast cancer, heart attacks, and stroke among HRT users, but a decrease in colon cancer and fractures. The authors concluded that HRT did not decrease the health risks for the general population of postmenopausal women; in fact, there were more reported heart attacks among women using HRT, though there was no difference in the death rate of women who used HRT over women who did not. A report published in the journal in May 2003 found that in postmenopausal women age sixty-five or older, using HRT composed of estrogen plus a progesterone increased the risk for Alzheimer’s disease.

Since then, however, the 2002 study has been reevaluated. Researchers have concluded that the study did not apply to many women who might be using HRT because the subjects in the research study were more than a decade older than most women were at the onset of menopause. We still await a definitive scientific study that can assess the risks and benefits of HRT accurately.

A 2015 report found that the most effective treatment of the vasomotor symptoms of menopause and the treatment that has the greatest effect in improving menopausal women’s quality of life is estrogen therapy. Estrogen and progesterone combinations taken for several years can have beneficial effects (fewer bone fractures) or harmful effects (increased risk of breast cancer, gall-bladder disease, clots forming in veins, and stroke). Estrogens given alone appear to be safer. They do not appear to increase the risk of developing breast cancer, although there is an increased risk of developing endometrial cancer.

Thus, the best strategy for a woman who has severe sleep difficulties because of menopause is to discuss with her doctor the pros and cons of using HRT medication specific to her medical condition and symptoms. If life with hot flashes is unbearable and results in disrupted sleep with all its related problems, she might find it worthwhile to consider using the medication. Similarly, if her sleep apnea came on abruptly with menopause, she might want to see whether HRT could reverse the problem.

If she decides to use hormone replacement, she should use the lowest effective dose of hormones. A combination of estrogen and progesterone is used to help reduce hot flashes. If the woman has had a hysterectomy she can take estrogen alone.


Some women have a disorder that might be made worse by hormone treatments. These women should not use HRT. Certain tumors, for instance, depend on estrogen for growth. These include breast cancer, cancer of the endometrium (lining of the uterus), and melanoma (pigmented cancer of the skin). Women who have had blood clots in their legs, especially if the clots have traveled elsewhere in the body (for example, the lungs), should not use HRT because hormones increase the risk of these dangerous clots.

Women who have a strong family history of one or more of these disorders should discuss using HRT with their doctor. They should have available as much specific information about the medical histories of their blood relatives as possible.


Low doses of antidepressants may be helpful in reducing hot flashes in women who choose not to use hormone replacement therapy. These include venlafaxine (Effexor, Pristiq), paroxetine (Paxil, Pexeva), and fluoxetine (Prozac, Sarafem). The antidepressants are less effective than HRT for severe hot flashes, and side effects may include weight gain, nausea, dizziness, and sexual dysfunction. They can even cause restless legs syndrome (see Chapter 11). These medications are not as effective as estrogen in relieving vasomotor symptoms but result in the largest improvement in psychological well-being.

Clonidine, normally used to lower high blood pressure, may improve hot flashes, but side effects include daytime sleepiness, dizziness, constipation, and dry mouth.

Another prescription medication is gabapentin, an anti-seizure medication that may help in improving hot flashes for women with disturbed nighttime sleep. Side effects may include daytime sleepiness, headaches, and dizziness.

Alternative Treatments for Sleep-Related Menopausal Symptoms

Many women are reluctant to use prescribed medications or HRT. A variety of alternative treatments are available, including traditional Chinese treatments, soy products, and herbal products.


Traditional Chinese treatments include acupuncture, herbal medicines, and moxibustion, in which heated “moxa” (made from the herb mugwort) is applied to the patient. These treatments can offer relief of some symptoms, but no large clinical studies into their effectiveness have been conducted.


Although there is a widespread belief that a natural substance is safer than a substance that has been manufactured or synthesized, we should not assume that an estrogen-like product made from soy or an herb is intrinsically safer than an estrogen-like product made in a lab or a product like Premarin, produced from chemicals obtained from the urine of pregnant mares. Women who have had breast cancer and are concerned that taking estrogen will increase the risk of a recurrence should be equally wary about taking any substance claiming to have estrogen or estrogen-like properties.

Certain molecules in some plants can affect estrogen receptors in humans. These compounds, called phytoestrogens, are found in soy and are chemically quite different from human-produced estrogens. More than a hundred reports have been published in the medical literature concerning the use of soy in menopause, but their results are contradictory. No detailed reports have been published on how soy products affect sleep disorders, and few of the studies have involved randomized controlled trials, in which the use of a treatment versus a placebo (sugar pill) is compared to determine whether having the treatment is more beneficial than having no treatment.

Hot flashes are reported to be much less common among Japanese women. Some scientists believe that this may be related to the Japanese diet, which includes many soy products. A study from Japan published in 1999 showed that not all soy products were equally effective in reducing symptoms of menopause; it wasn’t the amount of soy that was important, but the type of soy. The severity of hot flashes among Japanese women was reduced much more when they ate fermented soy products such as miso, natto, and tempeh than when they ate nonfermented soy products.

Research suggests that using between 30 and 60 grams of soy daily can be effective in reducing hot flashes. A half-cup of a soy product such as miso, natto, or tempeh contains 12 to 16 grams of protein. This means that a person will need to eat a large amount of these products to reach 30 to 60 grams, and gastrointestinal side effects such as gas, bloating, loose stools, and sometimes diarrhea are common.


Many women prefer to use herbal products for menopausal symptoms, including black cohosh, flax seed, dong quai, jiawei qing’e fang, keishibukuryogan, kava, chasteberry, and primrose. Some products may be effective for some populations (for example, keishibukuryogan seems to be more effective for women of Japanese descent).

Studies are continually being reported about their effectiveness, but we still lack well-done long-term studies of the risks and benefits of using most natural products. We thus do not know whether such products are safe when used for years or decades. There are few detailed studies of the effects of such products on sleep problems, and the ones that have been made have reported contradictory results. One study from China showed that black cohosh was effective in lessening hot flashes; another from Thailand found no difference between taking black cohosh and taking a placebo. One study found that 25 percent of preparations labeled cohosh did not contain cohosh!

There is concern that some products, including black cohosh, may cause liver toxicity. Kava may cause a rare but potentially fatal liver problem. The September 2016 Consumer Reports lists kava as one of fifteen dangerous supplements to avoid. The U.S. FDA has issued a consumer alert warning people about this problem. Health Canada (the Canadian equivalent of the FDA) concluded that there was insufficient scientific support for the safe use of kava, and that it therefore posed an unacceptable risk to health. In Canada, kava has been recalled from the market. Kava has also been banned in France, the United Kingdom, and Germany. Yet kava has been used for centuries in the South Pacific, so the problems experienced in other countries may lie in how kava is manufactured in the West.

Choosing a Sleep Problem Treatment

After consulting with their doctor or health care provider, and perhaps doing research of their own (a good online resource is the National Institutes of Health website,, women seeking to treat sleep problems caused by night sweats and hot flashes should base their decisions on what seems best for them. Some authorities recommend the use of HRT for four years followed by annual reevaluation. The individual woman must decide if the sleep symptoms caused by estrogen deficiency are sufficiently severe and disruptive to warrant treatment. Although such treatment will improve the symptoms, she must consider that she may be increasing her risk of cardiovascular disease and breast cancer. She should also take into consideration that HRT may carry with it the possible benefit of reducing risk of gastrointestinal cancer and problems related to osteoporosis. Each woman should take her own family history into account.

A 2016 review in JAMA concluded that no strong scientific evidence supports the use of any natural product for the long-term treatment of menopausal symptoms, and no research has been done on the long-term effects of using these products. At best, the report stated that phytoestrogen products modestly reduce hot flashes but have no effect on night sweats. Until better data are available, women will have to consider with their doctors the risks and potential benefits of such treatments. Many women do use them, and more scientific data should become available as more research is done. It is important, therefore, for women to continue to monitor the results with their doctors.

Disorders Causing Sleeplessness in Postmenopause

Whether they have hot flashes or not, many menopausal women develop insomnia. The reason may be related to the fact that estrogen has many effects on the central nervous system. It is possible that the decrease in estrogen affects the centers of the nervous system that are involved with sleep. In addition, some conditions occur more frequently in older people and, thus, in postmenopausal women. These include:

Mood disorders (discussed in Chapter 16)

Sleep apnea (discussed in Chapter 12)

Movement disorders (discussed in Chapter 11)

Painful conditions, including arthritis (discussed in Chapter 15)

Diabetes (discussed in Chapter 15)

Various cancers (discussed in Chapter 15)

Virtually any condition in this group—and often the medications used to treat them—may be associated with sleep problems. For a woman suffering from one or more of these conditions, the estrogen deficiency of menopause simply complicates an already troublesome part of life.

Perhaps the most troublesome problem is sleep apnea. Although for many years doctors believed that sleep apnea was rare in women, this disorder is actually extremely common, affecting at least 2 percent of adult women. Most women with sleep apnea are postmenopausal; the average woman with sleep apnea is about fifty years old. Harvard University research published in JAMA in 2003 suggests that by age fifty, women present roughly the same number of new sleep apnea cases as men. Just as estrogen and progesterone before menopause seem to protect women from cardiovascular disease, these hormones also seem to protect women from sleep apnea. Progesterone, which is produced during the menstrual cycle, stimulates breathing, and estrogen is probably responsible for where fat is deposited in a woman’s body. When premenopausal women become obese they tend not to have fat deposited in the neck that would increase the risk of apnea.

A recently discovered hormone, leptin, which is produced by fat cells, may stimulate breathing in obese people and may prevent them from developing apnea. This hormone also suppresses appetite. Some people may develop a resistance to the effect of the hormone and so put on more weight and develop apnea.

As a group, women with sleep apnea are older and more overweight as measured by body mass index than are men with the disorder. A Pennsylvania study showed that sleep apnea was much more common among postmenopausal women (2.7 percent) than premenopausal women (less than 1 percent). The same group found that almost all premenopausal women as well as post-menopausal women on hormone replacement therapy with sleep apnea were overweight. Postmenopausal women on HRT had apnea less frequently (0.5 percent) than postmenopausal women not on HRT. Thus, HRT seems to protect against developing sleep apnea. Other researchers have found that apnea is more common in postmenopausal women, affecting perhaps 10 percent of them. In some countries, such as Greece, women diagnosed with apnea were less likely to be obese than American women with the problem.

Women with symptoms suggesting sleep apnea are evaluated exactly as men are, and they receive the same treatments. The focus is on using CPAP, encouraging weight loss, and avoiding alcohol. An obvious question is whether postmenopausal women with apnea should be treated with hormones. In several articles in the medical literature that could be considered pilot studies or reports of individual cases, the authors usually concluded that there may be a benefit in treating postmenopausal women with sleep apnea with hormones (especially estrogen). However, the published results are not highly supportive of the use of HRT to treat sleep apnea in postmenopause because no long-term studies have been done. Large randomized control studies are needed to establish whether HRT works and what constitutes the correct dosage.

Breast Cancer

Breast cancer (which also occurs in men, but less frequently) is a major problem for women before and after menopause, and its treatment can lead to sleep disorders. Because the treatment of breast cancer may result in estrogen deficiency, women who are undergoing or have undergone treatment for breast cancer may have hot flashes that are more severe than those in women going through a normal menopause. In one study, two-thirds of women treated for breast cancer had hot flashes; almost all developed insomnia, and about a third developed a major depressive disorder.

Along with the anxiety of being confronted with a breast cancer diagnosis, the patient still has to face treatment, which often causes great emotional distress. Surgery, loss of a breast and the resulting damage to a woman’s self-image, and the use of drugs that may cause acute menopausal symptoms and hair loss can all lead to sleeplessness. Chemotherapy and radiation therapy can also cause insomnia and daytime tiredness.

Breast cancer patients cannot use estrogen-containing medications (HRT) to stop the hot flashes because tumor cells grow more rapidly when exposed to estrogen; thus, these drugs may worsen the woman’s prognosis. Many women have tried soy products, but the efficacy and safety of such treatments in breast cancer are not well known. It is worth reemphasizing that we do not know with certainty at this time whether the estrogen-like chemical in plant soy is any safer than estrogen in pill form.

These patients may benefit from some of the treatments suggested for insomnia patients. In particular, seeing a psychologist, pain medications, or sleep-promoting medications may help women sleep during the most difficult periods. Some patients who develop major depression may require psychiatric treatment. Recent research reviewed in 2016 is beginning to focus on improving the daytime fatigue and cognitive deficits (“chemo brain”) in these patients with wakefulness-promoting drugs such as modafinil (see Chapter 20).


So far in this chapter we have reviewed the sleep issues related to the myriad of changes that occur in women after the end of the reproductive phase of their life. Though sleep problems related to hormone deficiencies are more common among women, some men also experience them when undergoing andropause, the ending of the reproductive phase of a male’s life. In contrast to the 100 percent of women who will become menopausal with aging, it is estimated that only about 1–2 percent of men develop a comparable reduction in the production of testosterone, the male sex hormone. The patients may develop anemia (a low blood count), a loss of sexual desire, muscle weakness, and insomnia. Some preliminary studies published in 2015 suggest that these might improve with testosterone replacement. (Astonishingly, there has been almost no in-depth research on sleep issues in these patients.)

But even for men who do not experience andropause, certain conditions can result in an equivalent syndrome: men with advanced prostate cancer or breast cancer who receive therapy to reduce levels of androgens (male sex hormones) can experience similar difficulties to those experienced by menopausal women. The men on such therapy frequently develop hot flashes and night sweats that may disrupt sleep, loss of interest in sexual activity and impotence, breast enlargement and tenderness, thinning of bone, low blood counts, weight gain, and loss of muscle mass. These symptoms may improve with time.

About thirty years ago, studies showed that males who were not producing testosterone might develop obstructive sleep apnea when they started on testosterone replacement. As a result of this early research, doctors are advised to be cautious when starting patients on testosterone who already have sleep apnea, or who have the risk factors for sleep apnea (obesity, for example).

Research published in 2016 suggests that for men with proven testosterone deficiency who have a preexisting cardiovascular disease, testosterone replacement may be useful in preventing future cardiovascular events.

Back to the Insomniac with Night Sweats

I arranged for my patient to have blood tests to rule out excess thyroid secretion as a cause of her symptoms; this disease can cause night sweats (see Chapter 15). She also had a sleep test, which did not demonstrate that she was suffering from restless legs syndrome or dangerous cardiac rhythms during sleep.

Her thyroid function and the amount of iron in her body were normal. She did not have an abnormal heartbeat when she slept or while awake. But her heart rate increased when she woke up during the night. The most impressive part of her sleep study was not the many squiggly lines on her chart, but the video that showed her tossing and turning and constantly changing her position. Even when she slept, she was pulling her blanket off and then on, looking frustrated when she awakened during the night. Following the various tests, it was clear that she had perimenopausal symptoms. Her estrogen levels were dropping, and she was experiencing a sleep problem typical of women in perimenopause. We discussed treatment options including hormone replacement therapy, but she was disturbed by the media stories about its potential dangers and reluctant to use any other medications. She elected to sweat it out.

Hormone levels affect women’s sleep throughout their lives. As the levels of sex hormones drop with the onset of menopause, it can trigger a variety of sleep disorders. Doctors are now beginning to understand the relationship between hormones and sleep, and options are opening up to treat these disorders. Hormones are not the only causes of sleep problems, however, and sometimes both doctors and patients have difficulty recognizing when a patient has one of the sleep disorders described elsewhere in this book.