THE MYSTERY. Most women have sleep problems during pregnancy and after the birth of the baby. Sleeplessness can be severe, often caused by disorders such as restless legs syndrome, preeclampsia, and sleep apnea.
Three months after giving birth to her first baby, a twenty-nine-year-old woman came to see me at the sleep clinic in a state of total exhaustion. Although most new mothers can expect to be fatigued by the demands of caring for a newborn, this woman’s lack of restful sleep was affecting the quality of her life and the care she gave her baby—she could not stay awake long enough during the day to care for him properly. She fell asleep while watching television or reading, during conversations, and even sometimes when driving her car, in spite of drinking six to eight cups of coffee a day.
More disturbing was the fact that her sleep problems had started during pregnancy, and because they went untreated she and her doctor had unknowingly put her life and the life of her child at risk. I was not surprised to find out that her full-term baby was underweight at birth—only five pounds, ten ounces—and that she had had two previous miscarriages. As I took her history, more details emerged. The patient had been thirty or forty pounds overweight before her pregnancy and had experienced daytime sleepiness for about ten years, but the sleepiness had become much more severe once her pregnancy began. When she was six months pregnant, she spoke to her doctor about this problem. She explained that she had become uncontrollably sleepy, often falling asleep even when she did not want to. Her snoring had also become much worse since her pregnancy began, and her husband had noticed for at least five years that she stopped breathing when she was asleep. Her doctor told her that it was possible that she had sleep apnea. But the doctor also advised her not to get any tests or treatment for her sleep disorder during pregnancy, explaining that it would be much safer to wait until the baby was born. Like many doctors, hers did not understand the serious health consequences of women’s sleep disorders.
Unfortunately for mothers-to-be, sleep problems are a normal part of pregnancy. A study from 2014 suggests that chronic sleep loss in pregnant women can result in cardiovascular and kidney problems in their offspring. The 1998 National Sleep Foundation poll on Women and Sleep found that almost 80 percent of women report more disturbed sleep during pregnancy than at other times. Most of these women mentioned their frequent need to urinate as the main reason. Other reasons were related to various symptoms of pregnancy: tiredness, pelvic pressure, insomnia, lower back pain, restlessness, leg cramps, and nightmares. Symptoms of chronic sleep disorders, such as restless legs syndrome or sleep apnea, can also appear at this time or can worsen. These symptoms vary within the three trimesters of pregnancy.
When they first become pregnant some women feel wonderful. Others feel awful. Some women’s sleep remains normal, while other women sleep poorly from the beginning of their pregnancy and find themselves becoming more tired during the day. As one twenty-nine-year-old first-time mother reported, “I found many short rests during the day and night was all I could do to combat my sleepiness. I don’t think there was one night that I didn’t get up about six or seven times to use the washroom or to get water or simply could not sleep while I was pregnant. I would sleep an hour, then awaken every hour during my whole pregnancy.” This difficulty sleeping is probably due to the effect on the brain of rising progesterone levels. Morning sickness, which is common in the first twelve weeks of pregnancy, can also cause women to awaken with severe nausea. The nausea and vomiting can be extreme and become a serious health risk, as was the case for Kate Middleton, the duchess of Cambridge. This condition is now called “nausea and vomiting of pregnancy.” The only medication approved by the FDA to treat it is a delayed-release combination of doxylamine succinate and pyridoxine hydrochloride (Diclegis).
During the second trimester many women experience fatigue or tiredness due to the demands on the body, the carrying of extra weight, and sleep problems related to the enlarging uterus. Some may find that though they are tired and want to spend more time in bed, they have trouble falling asleep and spend much of the night restlessly tossing and turning, trying to find a comfortable position. A more extreme version of this restlessness is a medically diagnosable sleep disorder called restless legs syndrome, an uncontrollable urge to move because of unpleasant tingling sensations in the legs. Some women develop other problems that keep them awake at night such as cramps in their calves or back pains.
In the second trimester, women may also start to experience heartburn at night, which may continue until the end of pregnancy. The heartburn is caused by acid from the stomach going back up into the esophagus, the tube that carries food from the throat to the stomach. One contributor to acid reflux is the extra pressure on the stomach caused by the enlarging uterus. There are also muscles at the bottom of the esophagus that normally keep acid from backing up from the stomach. These muscles might not work as well during pregnancy. Having a snack, especially spicy foods, two or three hours before bedtime can bring on or exacerbate this condition.
During the last trimester of pregnancy, a wide range of problems can disrupt sleep. Some women develop nasal congestion, which may cause them to snore or develop the symptoms of sleep apnea. Some women have a marked worsening of restless legs syndrome. Others become breathless if they lie in certain positions or experience severe back pains that interfere with their sleep. Closer to the birth, breathing may also become more difficult because the uterus enlarges to the point where it pushes up on the diaphragm, the major breathing muscle. As pregnancy continues, the woman’s sleep becomes more and more difficult because the discomfort and sensations caused by the baby’s movements can lead to general overall restlessness. It is not uncommon for an expectant mother to stay awake all night toward the end of her pregnancy. I have seen some women who are completely unable to sleep twenty-four hours before going into labor. (Some also start to demonstrate nesting behavior: one woman used a sewing machine for the first time in her life on the night before her daughter was born and sewed curtains for the new baby’s room. She never used the sewing machine again!) Some scientists have suggested that the poor quality of sleep women may experience during pregnancy is the body’s way of preparing them for spending a great deal of time taking care of the newborn at night.
The sleep problems pregnant women encounter are magnified for women who carry more than one baby. Giving birth to several babies has become more common owing to advances in fertility treatments. And because the uterus can enlarge dramatically in women carrying several babies, the discomfort can be greater. Most women who are pregnant with more than one baby can only sleep on their sides. They cannot lie on their stomachs, and sleeping on their backs often results in breathing difficulties. The nutritional demands of the developing babies make the mother more likely to develop an iron or vitamin deficiency. Mothers carrying several babies often need to go to the hospital or be placed on bed rest before their due date to prevent giving birth prematurely.
When the mother gives birth she experiences a dramatic drop in her progesterone level, at the same time that other hormones are starting to kick in so that she will be able to breastfeed. After the baby is born, if there are no complications for the mother or the baby, the mother’s sleep can return to normal fairly quickly, although “normal” is a relative term while she’s doing frequent night feedings. During delivery, excessive blood loss can occur. Additionally, some women develop an iron deficiency during pregnancy because the developing baby saps iron from the mother. The iron deficiency combined with the blood loss can lead to anemia (low red blood cell count). This can result in severe daytime fatigue, especially if the new mother is also suffering from sleep deprivation because she is awakened for nocturnal feedings or by the baby’s crying. If the baby was delivered by caesarean section, the mother may also experience substantial pain and discomfort, which can contribute to poor sleep.
In addition to the two sleep disorders that are often seen in pregnant women—sleep apnea and restless legs syndrome—the normal discomfort, pain, and varied sensations associated with feeling the baby develop inside her can cause the mother to experience insomnia. This can be dangerous, for lack of sleep has been associated with a higher rate of miscarriage. It is important for expectant mothers to get the sleep they need during pregnancy. In Chapter 10, I offer suggestions for sufferers from insomnia, but some need to be modified for pregnant women.
First of all, I must caution pregnant women seeking relief against using some remedies that they might have used to combat insomnia before pregnancy. Sleeping pills, alcohol, or over-the-counter medications and herbals are not recommended to help pregnant women sleep through the night. Scientists do not know what long-term risks to the baby these medications or supplements might entail. But there are other options, involving behavior modification, open to pregnant women suffering from insomnia that can offer them some much-needed relief.
Short naps can be extremely helpful. The emphasis should be on short—too long a nap might interfere with nighttime sleep. A good time to nap is in the early afternoon, and the naps should be no longer than twenty to forty minutes.
Women who get heartburn at night should avoid spicy food, acidic fruit juices, and alcohol. They should not eat big meals and probably not eat anything in the two to three hours before they go to bed. Even naps should be put off until at least a half hour after eating. If the heartburn is severe, women may want to change their position during sleep, leaning against several pillows or even resting in a recliner. Women whose heartburn seriously interferes with their sleep should consult a doctor, who might prescribe an antacid such as Tums, which will have the added benefit of providing calcium. A glass of skim milk could offer temporary relief, but pregnant women should avoid whole milk, which can cause more acid to form. Expectant mothers should be careful not to drink too much milk to relieve heartburn as the calories can lead them to put on extra weight, which can in turn lead to sleep apnea.
Perhaps the most effective way for pregnant women to fight insomnia is to experiment with sleeping positions until they find the most comfortable one. Most women have to train themselves to sleep in a different position from those they used before pregnancy. For instance, women who tended to sleep on their stomachs can no longer do this and women who slept on their backs might now find it too difficult to breathe. Sleeping flat on the back might also result in the uterus pressing on the main artery of the woman’s body, the aorta, which could reduce blood flow to the baby. For many women, sleeping on the side becomes the most comfortable position; it will also increase blood flow to the baby by relieving pressure on the aorta. Women who are not used to sleeping on their sides might find that putting a pillow between their knees can improve their comfort level.
Unfortunately, there is no absolute remedy for pregnancy-related sleeplessness except giving birth.
Restless legs syndrome (RLS) frequently occurs during pregnancy. (See Chapter 11 for a fuller discussion of RLS.) Many women with RLS recall that their first episode of the disorder occurring during a pregnancy. Women with RLS feel an irresistible urge to move their legs while they are trying to sleep. Moving or walking relieves this urge. In some patients, RLS is inherited. Women who have inherited RLS are much more likely to have increased symptoms of restlessness and a crawly sensation under their skin during pregnancy.
A study done at the University of California, published in 2001, focused on the likelihood of women developing RLS during pregnancy. None of the women studied had the syndrome before they became pregnant, but by the end of their pregnancies, 23 percent of them were afflicted. They also experienced insomnia and a depressed mood. Those who developed RLS were found to have iron deficiencies and/or folic acid deficiencies before becoming pregnant, both known causes of RLS. Women with an iron deficiency should have it treated. So common sense—as well as research reported in 2015—mandates that women who develop restless legs syndrome during pregnancy should have their iron status checked by a doctor, who will probably prescribe a multivitamin preparation containing folic acid. Pregnant women need to keep their folic acid levels up for another reason as well: studies have shown that mothers who take folic acid are less likely to have children born with a neurological malformation.
RLS can be miserable for pregnant women. They may develop restlessness in their legs, not only at night but during the day as well. A detailed review published in 2015 summarized treatment options and concluded that not one drug treatment for RLS was both safe and effective during pregnancy or while the mother was breastfeeding. The treatments that could be considered were mild to moderate exercise (most women learn that walking often helps), massage, pneumatic compression devices, iron therapy, and yoga, as well as treatment of sleep apnea if that were also present. One pneumatic compression device consists of a wrap around the lower leg that is inflated for five seconds every minute. This is used for an hour in the evening. Similar devices that are used to prevent blood clots in the legs might also be effective. The FDA has approved a device (Relaxis) that applies vibrations to the legs.
In most women, restless legs syndrome goes away with childbirth, although for some women the symptoms brought on by pregnancy can go on indefinitely. These women may benefit from seeing their doctor.
About a third of pregnant women snore. Since women are less prone to snoring than men, often the first time a woman snores is when she is pregnant. A 2015 study reported that pregnant women who snore and otherwise score high on a sleep apnea questionnaire are more likely to develop high blood pressure and to need a cesarean section. Some research studies have shown a frightening connection between snoring and a potentially dangerous medical condition called preeclampsia, a form of high blood pressure that can occur during pregnancy. Preeclampsia causes damage to the kidneys, which results in a great deal of protein being lost in the urine. Studies have found that pregnant women who snore are twice as likely to develop preeclampsia than those who do not snore, and women with preeclampsia are twice as likely to have smaller babies than those without it. Affecting about 7 percent of pregnant women, preeclampsia usually begins after twenty weeks into the pregnancy. Blood pressure goes up, causing damage to the kidneys. Women may experience few obvious symptoms, as high blood pressure and kidney problems can be difficult to detect without testing, though early in the pregnancy sufferers might have headaches or severe swelling of the ankles, or might have swelling of the face. The most obvious indicator is often snoring. (Some women who snore during pregnancy might have sleep apnea, which is discussed below.)
Thus, if a woman begins to snore while she is pregnant, she should have her blood pressure and urine checked, especially if she also suffers from headaches and swollen ankles. About one in twenty women with preeclampsia develops seizures as well as very severe high blood pressure and other problems. This even more serious condition is called eclampsia. Both conditions usually resolve soon after childbirth. Women with preeclampsia or eclampsia require immediate medical care, and some might benefit from a sleep study.
The dangers these conditions present highlight the importance of talking with a doctor about sleep problems—even seemingly insignificant ones such as snoring.
Some women experience sleep apnea before they become pregnant, and the condition worsens during pregnancy. In other women, the apnea develops during pregnancy. Screening for apnea by questionnaire can be useful in the second and third trimesters. The symptoms are similar to those of sleep apnea in women who are not pregnant: snoring, pauses in breathing during sleep, and severe daytime sleepiness. Some of the medical issues that occur during pregnancy have now been linked to sleep apnea in the mother. These include high blood pressure and gestational diabetes.
Research reported in 2010 and 2013 showed that when a pregnant woman has symptoms of sleep apnea she is more likely to have pregnancy-induced hypertension, preeclampsia, and gestational diabetes, or to require a cesarean delivery. Research reported in 2016 showed that mothers with sleep apnea are at greater risk of giving birth prematurely. The baby is liable to be less vigorous or to need to spend time in a Neonatal Intensive Care Unit. Some babies of mothers with sleep apnea might be large for their gestational age, and thus more prone to hypoglycemia, whereas others might be smaller than average at birth and are more likely to develop a metabolic disorder, or even cardiovascular disease, in adulthood.
It has also been suggested that women with sleep apnea are more likely to have miscarriages. The danger of sleep apnea is that the blood oxygen level in the mother can drop to very low levels. Because the baby is dependent on the mother for oxygen, a pregnant woman with sleep apnea must be treated as soon as possible. The usual treatment is continuous positive airway pressure (CPAP), a mask worn over the nose connected by a hose to a machine that increases pressure in the breathing passage. The system can be used by people who sleep on their sides, as many pregnant women do.
In addition to the risks a pregnant woman’s sleep apnea presents to her fetus are the problems it presents for her not only during pregnancy but after the baby is born, when the new mother will have many responsibilities. Treatment of her sleep apnea can help ensure that she gets a good night’s sleep and be wide awake and alert during the day to cope with the demands of her baby. Dealing with the needs of a new baby is not easy for any woman, but it is extremely difficult for a woman with untreated sleep apnea. The first pregnant woman I saw who had sleep apnea had to be started on emergency treatment immediately after delivering the baby because there was no one else to care for her child.
The sleep difficulties seen during pregnancy are often followed by sleep deprivation after the baby is born. About 20 percent of immediately postpartum mothers may have sleep apnea. The new obligations involved in caring for the baby eat away at the mother’s time. For breastfeeding mothers, one of these is waking up at night to feed the baby. Often a newborn baby sleeps in the parents’ bedroom or bed, and can disturb new mothers who are trying to sleep. Mothers who can get outside help should do so. They should also make a point of napping when the baby naps. Finally, new mothers should be careful not to drive when sleepy.
Although new mothers are usually euphoric after giving birth, some women have changes in mood that can range from feeling temporarily blue to having an episode of full-blown clinical depression. Sleeplessness is a common symptom of depression. It is believed that these abnormal moods are caused by reduction in the levels of the hormone progesterone. Women who have severe depression after childbirth often have had previous depressive episodes, although those episodes might not have been diagnosed. Postpartum depression can have devastating results (for example, depressed mothers might commit suicide or harm the newborn), and new mothers who have depressive symptoms should receive immediate medical attention. I discuss these symptoms fully in Chapter 16.
We gave the patient a sleep test to measure how many times she stopped breathing while she slept. The test revealed that she had severe obstructive sleep apnea syndrome, which caused her to stop breathing 136 times an hour, and almost every time her breathing stopped, her brain awakened for a few seconds. Stopping breathing more than 5 times an hour is considered significant, so this new mother’s sleep apnea was extremely severe. When breathing stops, the amount of oxygen in the blood decreases. Correspondingly, her blood oxygen level dropped to dangerous levels; she spent about 11 percent of her sleep time with her blood oxygen level below 80 percent. During these episodes, 20 percent of her blood was not carrying oxygen, which put great stress on her cardiovascular system. (These oxygen levels are typical in people sleeping at fifteen-thousand-foot altitudes but abnormal for those at sea level.) The sleep apnea was putting her life and the life of her child at risk and was the probable cause of the baby’s low birth weight.
After the first sleep test, which confirmed her severe sleep apnea, the sleepy new mother was tested on a CPAP mask. The result was a dramatic improvement—her apnea episodes disappeared. Her sleep became completely normal and her blood-oxygen levels never again decreased to their previously dangerous lows. Two months later, after using the CPAP at home every night, she told me that she felt great because she was no longer sleepy. “I can’t sleep without [the CPAP],” she said. “Everyone says I’m better.” With the assurance of a good night’s rest, she felt better able to contend with her daily responsibilities.
Women need to become more aware of the impact of sleep disorders on their health. Although pregnancy is often a time of great joy and excitement for a woman, it can also seriously affect her sleep. The majority of women have problems with sleep during pregnancy, ranging from mild to severe. It is important that women and their doctors know about sleep problems that affect women during normal, multiple-birth, and high-risk pregnancies.
Most sleep problems that occur during pregnancy improve after the birth of the baby. The end of a woman’s reproductive years, however, do not signal the end of potential sleep problems. After the onset of menopause, women often find themselves experiencing sleep problems. In the reproductive years, fluctuating sex hormone levels are often the cause of sleep disturbances; in the menopausal years, it is the lack of sex hormones that cause the problems.