Insomnia Causes During Pregnancy

Tossing, turning, turning, tossing. Insomnia, being unable to fall asleep and stay asleep, is a miserable experience leading to daytime fatigue, poor concentration, and even health complications. While insomnia can occur in all conditions in life, it is especially prominent in pregnant women. Keep reading to learn about insomnia causes during pregnancy organized by trimester.

Insomnia causes during pregnancy
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What Is Insomnia?

Insomnia is a sleep disorder characterized by difficulties falling asleep, staying asleep, and/or awaking too early in the morning. The disorder may present as acute—brought on briefly by stressful life circumstances (i.e. impending event, the night before a job interview, etc.). However, insomnia is classified as chronic when occurring three or more times per week for three or more months. The physiological and psychological changes taking place during pregnancy produces a chronic form of insomnia because the symptoms continue throughout all three trimesters, as well as after birth.

Symptoms of Insomnia

Regardless of the underlying cause of insomnia, a set of basic symptoms accompanies a lack of restful sleep. Pregnancy only increases insomnia symptoms tenfold because the body is attempting to regulate its functions for two while growing new life.

  • Fatigue—low energy levels, daytime sleepiness  
  • Non-restorative sleep—feeling “unrefreshed” or restless
  • Cognitive impairment—poor concentration, memory problems, inattention
  • Behavior problems—impulsiveness and aggression  
  • Mood changes—anger, irritability, depression, anxiety

Insomnia Causes During Pregnancy: Trimester by Trimester

Pregnancy is divided into periods known as trimesters. A full-term pregnancy is approximately 40 weeks, which make up a total of three trimesters. Insomnia is common in each trimester. While insomnia causes during pregnancy are similar across trimesters, the severities progress as hormones and development fluctuate.

Insomnia Causes During Pregnancy: First Trimester

The first trimester includes the first twelve weeks of pregnancy. Their bodies are adapting to the influx of hormones and the excitement and worries over the new life growing inside them, which often introduces the beginnings of insomnia that can begin as early as after conception. Women in the first trimester of pregnancy who also have insomnia are prone to fatigue and excessive daytime sleepiness. Studies by sleep experts indicate that the number of hours of sleep increases, while sleep quality decreases in the first trimester.


The predominant hormone in early pregnancy is progesterone. High levels of progesterone results in drowsiness. Feeling more tired than normal leads to frequent napping during daylight hours. Although naps are perceived as healthy to allow the body time to rest and repair, it interferes with the sleep cycle—making sleeping through the night less likely. Progesterone is also responsible for causing uncomfortable hot flashes and night sweats which contribute to insomnia.

Restless Leg Syndrome

Restless leg syndrome is a sleep disorder associated with an overwhelming urge to move the legs due to sensations of pain, burning, tingling, and aching. These symptoms of restless leg syndrome worsen at night. Nearly thirty-four percent of pregnant women suffer from restless leg syndrome sometime throughout their pregnancy. Insomnia is a consequence because the discomfort wakes them. Many factors play a role in restless leg syndrome such as vitamin deficiencies (i.e. iron, folate, and vitamin D) that are more common during pregnancy.

Gastrointestinal Complaints

Morning sickness is a hallmark complaint, especially in the first trimester. Do not let the term “morning sickness” fool you. Nausea and vomiting have the tendency to appear any hour of the day. It adds to insomnia by causing early awakenings and interferes with falling asleep.

Other gastrointestinal complaints may cause insomnia too. For example, the first trimester is infamous for constipation from the higher levels of progesterone that slow muscle contractions to cause not only increased nausea, but reflux, stomach cramps, and heartburn. Sleeping through the discomfort is a difficult task for some pregnant women.


While pregnancy is a joyful occasion for many families, bringing a baby into the world is far from a stress-free event. Soon-to-be mothers worry about finances and whether they are financially secure enough to support a child. They also may have concerns about their parenting abilities and the health of the child. Compared to the daylight hours packed full of activities, the night is intended to be slower-paced and relaxing. Instead of sleeping, they experience anxiety over the new changes because they have more time to ponder think.

It is important not to allow stress to morph into untreated depression. Below are the signs that typical pregnancy-stress has turned into a more serious disorder.

  • Excessive anxiety about the baby
  • Low self-esteem
  • Feeling inadequate about becoming a parent
  • Avoiding prenatal care
  • Substance use (smoking, drinking, etc.)
  • Loss of interest in regular activities
  • Weight loss and decreased food intake
  • Irregular sleep patterns

Frequent Urination

Frequent urination can be one of the beginning signs of pregnancy. The uterus is still sitting low in the body, which compresses the bladder. Additionally, the rise of the hormones progesterone and human chorionic gonadotropin (HCG) increases urine production. Countless bathroom trips in the night are a huge cause of insomnia during pregnancy.

Insomnia Causes During Pregnancy: Second Trimester

The second trimester of pregnancy accounts for weeks 13 to 28. As the rapidly fluctuating hormones begin to level out, energy levels peak. Women feel less tired with improvement in sleep their quality. Women might experience temporary relief, but insomnia and its effects remain even in the second trimester.


Nausea from morning sickness decreases significantly, which is helpful for insomnia. However, heartburn increases during the second trimester of pregnancy. The uterus shifts upward to support the developing fetus, compressing organs such as the stomach and the intestines. The pressure on these vital gastrointestinal organs stimulates heartburn and reflux that is not optimal for restful sleep.

Leg Cramps

Leg cramps appear in the second trimester. Experts suggest that women get leg cramps during pregnancy due to tension on the muscles and altered circulation from the pressure of the baby on blood vessels. Leg cramps are also connected to calcium deficiency. The night is the prime time for the discomfort of leg cramps. The pain has the potential to make sleep restless.

Vivid Dreams

Dreaming probably does not seem like a negative thing. After all, dreaming occurs while asleep! But up to seventy-two percent of pregnant women report nightmares that cause insomnia. Changes in sleeping patterns during pregnancy result in vivid, intense dreams that lead to recurrent awakenings and difficulty falling back to sleep. Nightmares centered around the anxieties of their baby and becoming a parent are not uncommon. With mid-sleep cycle awakenings from dreaming, excessive urination, or other pregnancy discomforts, pregnant women have greater dream recall—so they remember their dreams in detail.

Shortness of Breath and Snoring

Like the gastrointestinal distress that is an insomnia cause during pregnancy, shortness of breath and snoring are two symptoms brought on by the upward shifting of the uterus. To make room for the developing fetus, the uterus moves higher and compresses the diaphragm. Breathing becomes shallow and many snore. Some acquire sleep apnea—a sleep disorder distinguished by pauses in breathing. This is connected to insomnia because sleep quality is reduced as the body attempts to wake the person who is not receiving sufficient air.

Changing Sleep Positions

Insomnia Causes During Pregnancy

Most of us are accustomed to sleeping in a certain position at night. As a body makes room for a growing fetus and all that it entails, the once soothing sleep position can become uncomfortable. For example, a pregnant woman who generally sleeps on her back might notice herself changing positions to accommodate shortness of breath, or someone who sleeps on their right side may have to switch to the left to avoid gastrointestinal reflux. The tossing and turnings to find a new routine are another aspect of the restlessness of insomnia causes during pregnancy.

Insomnia Causes During Pregnancy: Third Trimester

Accounting for weeks 28 to 40, the third trimester is the final stage of a full-term pregnancy. Women are increasingly uncomfortable due to the stress of carrying a near completely developed baby. Thus, insomnia is the worst in the third trimester. Causes for insomnia are comparable to the other trimesters, yet exacerbated. Urination increases in frequency, forced sleep positions are more distressing, restless leg syndrome intensifies, and heartburn and reflux prevent a restful repose.


Nobody cares to suffer pain. Still, pregnant women experience their fair share. Although they have a cute little bundle of joy at the end of the 9 months, they have countless sleepless, insomniac nights from the various aches and pains pregnancy inflicts on their bodies. The third trimester is the period in which pain significantly affects sleep.

  • Back pain—As the pregnancy progresses, the lower back muscles become strained.  
  • Hip pain—Hip pain and pain in other joints is common because the connective tissue loosens due to pregnancy hormones.
  • Carpal tunnel—Carpal tunnel is a condition characterized by the narrowing of the wrist tunnel, which pinches the nerves. This creates symptoms such as pain, tingling, weakness, and numbness in the hand. It sometimes develops in the third trimester of pregnancy because pregnancy swelling puts pressure on the nerve. The symptoms worsen at night as fluid redistributes to the limbs.
  • Breast tenderness—Breasts are tender and sore as they fill with colostrum (i.e. early breast milk).

Fetal Movement

The first flutters of new life is an awestruck feeling. However, the slight movements of the first and second trimesters intensify in the third trimester. The fetus kicks as it prepares to move lower into the birth canal for labor. Fetal movements are the source of multiple early awakenings in the night.

Experts say that the fetus does not move more during the night, but because the mother is in a horizontal position while sleeping, they are more likely to sense fetal movement while trying to sleep. In the third trimester, the baby is larger in size and fetal movements may be uncomfortable if pressing on the organs.

Birth Anxiety

As previously mentioned, stress and anxiety impact insomnia. Earlier in pregnancy, stress revolves around finances and parenting, but as the baby’s due date draws closer, many women display concerns over giving birth. Worries include enduring the pain of labor, potential labor complications, sleepless nights caring for the child, breastfeeding, and more. These worries keep pregnant women up at night. In severe cases, birth anxiety can lead to panic attacks.

Braxton-Hicks Contractions

Braxton-hicks contracts are intermittent contractions followed by relaxation of the uterine muscles. These “false labor” contractions that mimic period cramps begin late in the second trimester or in the third trimester of pregnancy. Together, the hormones oxytocin and melatonin initiate Braxton-hicks contractions. They prepare the body for actual labor. Studies show contractions commonly arise between the hours of 8PM and 2AM because hormones that cause the uterus to contract are released in larger amounts at night. The pain contributes to insomnia.


Preeclampsia is a condition affecting one-in-ten pregnancies. Usually occurring in the third trimester, women with preeclampsia have a sudden rise in blood pressure, protein in their urine, and fluid retention (edema). If untreated, preeclampsia can result in eclampsia—a rise in blood pressure causing seizures and the risk of going into a coma.

Hormones inducing high blood pressure influence the circadian rhythm, which is also known as the sleep cycle. The Journal of Clinical Sleep Medicine confirms that high blood pressure in conditions like preeclampsia cause insomnia during pregnancy, as it poses the risk of obstructive apnea, reduces sleep quality, and threatens the health of the fetus by restricting its growth.

Insomnia Causes During Pregnancy: Postpartum  

A loss of sleep is normal after birthing a baby. Parents are aware they will be up at all hours feeding, changing, and rocking. They must rest when the baby does. Some new mothers struggle to do so. They continue to have difficulty falling or staying asleep, despite their desire for rest. The culprit for postpartum insomnia after pregnancy are hormones.

Sleep specialists conclude that the rapid decline in estrogen and progesterone, along with the spike in oxytocin, causes hyperarousal that fuels insomnia. Insomnia in pregnancy can linger for weeks into the postpartum period. Given time, it does subside and there is a wide array of options available for insomnia treatment.


Haney, A., Buysse, D. J., & Okun, M. (2013). Sleep and pregnancy-induced hypertension: a possible target for intervention?. Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine9(12), 1349–1356.

Zahn, V., and W. Hattensperger. 1993 “Circadian Rhythm of Pregnancy Contractions”. Z Geburtshilfe Perinatol. 197(1):1-10.

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