Sleep During Pregnancy: Rest Better Each Trimester

Pregnancy places extraordinary demands on your body. Your cardiovascular system increases cardiac output by up to 50%, your respiratory rate rises, and hormone levels shift dramatically. These changes are essential for fetal development — and they make quality sleep harder to achieve.

Sleep is one of the most powerful tools you have to support a healthy pregnancy. This guide explains why sleep becomes difficult during pregnancy and offers actionable strategies for each trimester.

Why sleep during pregnancy is important

Regularly getting enough sleep is a key part of prioritizing your health. Sleep deprivation can make daily activities like thinking, working, and communicating with others more difficult due to symptoms including fatigue, irritability, cognitive dysfunction, anxiety, and depression.

It can also negatively impact the whole body physiologically, from the brain to the heart, and the metabolic, nervous, and immune systems, and may lead to trouble concentrating, increased anxiety, cardiovascular disease, hypertension, headaches, and more. While consistent sleep is vital everyday, it's especially important for pregnancy.

A lack of sleep has been linked to a wide range of issues during pregnancy, including trouble with remembering and paying attention, abnormal fatigue during the day, a greater chance of falling, and an increased likelihood of experiencing the symptoms of depression.

Research has also linked sleep deprivation to negative outcomes during labor. Sleep deprived patients were found to be more likely to experience pain and discomfort during labor, longer labor times, and an increased incidence of preterm labor and cesarean procedures.

Why sleep during pregnancy can be difficult

There are several factors that can contribute to sleep disruptions and deprivation during pregnancy. Many of the physiological changes that occur during pregnancy make sleep more difficult.

For example, cardiac input and heart rate increase to pump a higher blood volume through the body and the uterus — and an elevated heart rate can make it harder to fall and stay asleep. The kidneys are also taxed with filtering this elevated blood volume, and produce more urine as a result. As pregnancy progresses, extra pressure is placed on the bladder, requiring more nightly bathroom visits.

Gastrointestinal symptoms like reflux or heartburn can worsen at night, causing discomfort that disrupts sleep. Leg and back pain is common, especially during the later trimesters due to the increased stress put on the body from supporting the growing uterus.

Changes in hormone levels can also cause a variety of symptoms that can get in the way of a good night's sleep, including shortness of breath, nausea, elevated body temperature, leg cramping, and vomiting.

Common pregnancy sleep disruptions

Pregnancy insomnia

Hormonal shifts and physical discomfort often lead to pregnancy insomnia. You might find it difficult to fall asleep, stay asleep, or wake up feeling rested. This is a normal physiological response to the increased demands on your body.

Restless legs syndrome

Many pregnant individuals experience restless legs syndrome, characterized by an uncontrollable urge to move the legs, especially at night. This sensation can severely disrupt your ability to enter deep, restorative sleep stages.

How to improve sleep during pregnancy

It's easy to see how getting quality sleep can be challenging during pregnancy. Fortunately, that doesn't mean it's impossible to get adequate rest when pregnant. There are plenty of ways to address the unique challenges associated with each stage and improve sleep during each trimester.

First trimester

During the first trimester, progesterone levels rise to promote proper early development. High levels of progesterone have been linked to symptoms such as excess daytime fatigue and feeling very warm or hot. The nausea and vomiting that come along with morning sickness can also occur at night, making it difficult to get comfortable or stay in bed for long enough to get consistent sleep.

Sleep deprivation during the first trimester has been linked to health issues including gestational diabetes and high blood pressure. Not getting enough sleep early in pregnancy can also cause increased levels of stress and more depressive symptoms.

The first trimester is the perfect time to lay the groundwork for healthy sleep habits that will support quality sleep throughout your entire pregnancy. Simple adjustments to your nightly routine can make a big difference in how well you sleep, such as limiting screen time right before bed and optimizing your sleep environment.

Make sure your room is cool and dark, that your bed and sheets feel comfortable, and that the space is free of distractions. Additionally, avoiding late meals and spicy or fatty food items can help reduce digestive discomfort from heartburn and acid reflux.

Second trimester

The second trimester often brings relief from certain sleep difficulties. Hormone levels stabilize and bathroom visits decrease. However, new challenges emerge — including swelling, headaches, nasal congestion, and lower back pain.

Sleep is more frequently disrupted during the first and third trimesters, making the second trimester your best opportunity for rest. Prioritizing sleep during this period supports proper development and overall health. Sleep deprivation during the second trimester has been linked to diminished quality of life, mental health challenges, and gestational diabetes.

Simple adjustments during the second trimester can improve your sleep quality.

Side sleeping is the most comfortable position during the second trimester. Left side sleeping increases blood flow and nutrient delivery through the placenta. Morning or afternoon exercise improves sleep quality better than nighttime workouts.

Third trimester

The third trimester is often the most challenging period for consistent, restful sleep. Lower back pain, muscle aches, heartburn, restless legs syndrome, and frequent urination make falling and staying asleep difficult. Insomnia, snoring, and sleep apnea are also common during this stage.

Sleep deprivation during the third trimester has been linked to preterm birth, preeclampsia, gestational diabetes, longer labors, and higher cesarean rates. Quality sleep during this period reduces depressive symptoms and supports better breastfeeding outcomes.

Continuing to sleep on your left side reduces discomfort and supports proper development. A pregnancy pillow or smaller pillows between your legs, behind your back, or under your belly reduce pressure and relieve muscle aches.

The third trimester can be stressful. Additional sleep hygiene techniques promote relaxation: listening to music or taking a warm bath before bed, light yoga during the day, white noise machines, or deep breathing and meditation.

Tips to improve sleep naturally during pregnancy

Maintain a consistent sleep schedule by going to bed and waking at the same time daily to regulate your circadian rhythm and improve sleep efficiency.

Limit fluid intake in the hours before bedtime to reduce nighttime bathroom visits. Taper off fluids after dinner to sleep through longer stretches.

Practice relaxation techniques like deep breathing or prenatal yoga before bed to lower your heart rate and signal to your nervous system that it's time to wind down.

Keep your bedroom cool, dark, and quiet to support deeper, more restorative sleep stages.

Monitor your sleep and pregnancy trends with WHOOP

Understanding how your body responds to pregnancy requires continuous measurement. WHOOP measures your sleep performance, detailing the time you spend in each sleep stage, your sleep efficiency, and your wake events. You can log specific behaviors in the Journal — like side sleeping or using a pregnancy pillow — to see how they impact your recovery.

With Pregnancy Insights, WHOOP provides weekly biometric updates to help you understand how your resting heart rate and HRV (Heart Rate Variability) naturally shift as your pregnancy progresses. This data empowers you to make informed decisions about your daily strain and rest.

Frequently asked questions about pregnancy sleep

When does pregnancy insomnia start?

Pregnancy insomnia can begin as early as the first trimester due to rapid hormonal changes, particularly rising progesterone levels. It often peaks in the third trimester as physical discomfort and frequent urination increase.

What is the 5 3 1 rule in pregnancy?

The 5-3-1 rule is a guideline used to identify active labor, not a sleep technique. It refers to contractions that are five minutes apart, last for one minute, and continue for one hour. If you experience this, it is time to contact your healthcare provider.

How does sleep position affect pregnancy?

Sleeping on your left side is generally recommended as it maximizes blood flow to the uterus and improves kidney function. Back sleeping in later trimesters can place pressure on major blood vessels, which may cause dizziness or reduce circulation.