Many people have a favorite position for going to sleep. However, if a person’s most comfortable position is tummy down, they might wonder whether that is safe during pregnancy.

When pregnant, many people have trouble getting or staying comfortable while sleeping.

People may worry that their sleeping position will affect their baby.

In this article, we will examine whether sleeping on the stomach while pregnant is safe. We will also look at the best sleeping positions during pregnancy and the ones to avoid.

A pregnant person about to sleep on their stomach.Share on Pinterest
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There is no evidence to suggest that sleeping on the stomach during the early weeks of pregnancy causes harm. The uterine walls and amniotic fluid cushion and protect the fetus.

However, most people find it increasingly challenging to sleep on their stomach as their abdomen grows and raises the torso, altering the natural curvature of the spine.

Sleeping on the stomach may also cause neck and shoulder problems, such as pain, stiffness, and soreness. Some people experience lower back pain and pelvic girdle pain during pregnancy, which make it more difficult to sleep.

Researchers have observed links between a reduction in sleep quality and several outcomes during pregnancy, such as:

A person who prefers sleeping on their stomach may consider using a stomach sleeping pillow with an area cut out for the belly.

Doctors usually recommend people sleep on their side during pregnancy. A 2019 review suggests that sleeping on either side while pregnant is safe.

Left side

Many consider sleeping on the left side the “ideal” sleeping position during pregnancy. This is mostly due to blood flow.

A large vein, known as the inferior vena cava (IVC), runs parallel to the spine on the right side. The IVC carries deoxygenated blood from the lower body and back to the right side of the heart for oxygenation.

As the IVC is to the right of the spine, lying on the left side may allow optimal blood flow to the heart and blood, and nutrients to reach the fetus.

Right side

Earlier research investigating people sleeping on their right side during pregnancy found non-left sided sleeping linked with a higher chance of stillbirth.

In theory, sleeping on the right side, particularly in the latter stages of pregnancy, may compress the IVC, reducing blood returning to the heart and decreasing placental blood flow.

However, recent research indicates that people who sleep on their right side while pregnant are no more likely to experience late stillbirth than people who sleep on their left side. Going to sleep on either side appears to be equally safe.

The National Institutes of Health (NIH) funded an analysis in 2019 to examine sleeping position and adverse outcomes during pregnancy.

They found no connection between going to sleep on the back or right side until the 30th week of pregnancy and complications linked to a decrease in placental blood flow, such as:

  • an increased chance of stillbirth
  • reduced size of a newborn
  • high blood pressure pregnancy disorders, such as preeclampsia, eclampsia, and gestational hypertension

These findings suggest that the sleeping position in early to mid-pregnancy may not increase the chances of complications. However, the study did not observe the last 2 months of pregnancy.

Other research found sleeping on the right or left side throughout pregnancy to be equally safe.

Back sleeping

Sleeping on the back during the third trimester may increase the chances of stillbirth in a small number of people.

This is because the weight of the uterus could compress the IVC and aorta. The aorta is the large artery that carries oxygenated blood from the left side of the heart to other parts of the body. This compression could reduce blood flow to the fetus.

Research indicates that back sleeping from 28 weeks of pregnancy may increase stillbirth risk by 2.6 times compared with side sleeping. Side sleeping during the third trimester could reduce late stillbirth by almost 6%.

People who sleep on their backs during pregnancy may experience symptoms, including:

These symptoms may result in:

  • stillbirth
  • preeclampsia
  • low fetal birth weight
  • reduced fetal growth rate

People should not worry if they wake up on their back in the late stages of pregnancy, but they should roll onto their side to go back to sleep.

People who find it uncomfortable to sleep on their side can try placing a firm, supportive pillow under the abdomen to reduce lower back stress.

Placing a firm pillow behind the back and legs can also make it more difficult to flip over during the night onto the back.

People who find it difficult to sleep propped up could try placing pillows behind their upper back to find a comfortable angle.

People experience a wide range of symptoms and bodily and hormonal changes during pregnancy that may interfere with sleep, such as:

People can try a range of techniques to relieve their symptoms and improve sleep, including:

  • going to bed and getting up at the same time each day
  • aiming for 7–8 hours of sleep each night
  • drinking enough water
  • avoiding caffeine late in the day
  • avoiding long naps during the day
  • exercising regularly
  • trying gentle activities, such as yoga, swimming, or tai chi
  • eating a healthful, balanced diet
  • taking antacid medications to reduce acid reflux
  • avoiding spicy, fried, acidic, and fatty foods
  • eating smaller, more frequent meals
  • avoiding drinking too much water and other fluids before bed
  • trying iron and folate supplements for restless legs syndrome
  • eating a few plain saltine crackers before bed to reduce nighttime nausea
  • speaking with a doctor about sleep apnea or using a continuous positive airway pressure machine
  • using relaxation techniques, such as visualization, breathing exercises, or meditation

Pregnancy pillows

During pregnancy, a person sleeping on their side should keep their knees bent at a comfortable angle and place a thin, soft pillow between their knees to reduce lower back stress. A pregnancy pillow shaped like a crescent can offer support to the arms and knees alike.

People with heartburn can also try putting a pillow under their upper body to raise it slightly to reduce the risk of reflux.

During late pregnancy, people experiencing shortness of breath may also benefit from lying on their side or having pillows propping up their upper body.

Elevating the legs slightly with a pillow may also help individuals with leg swelling or pain.

It is generally safe for people to sleep on their stomach during pregnancy, although it may be uncomfortable and cause back or neck pain.

Research suggests that it is safe for people to sleep in whichever position they prefer until around 30 weeks of gestation. However, in the latter stages of pregnancy, people should try to sleep on their side — ideally, their left side for optimal blood flow to the fetus.

People should avoid sleeping on their back from 28 weeks of pregnancy to prevent adverse symptoms and outcomes.