Fetal Sleep Position

Updated November 22, 2023

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Table of Contents

What Is the Fetal Sleep Position?
Benefits of the Fetal Sleep Position
Who Should Sleep in the Fetal Position?
When to Consider Other Sleeping Positions

Key Takeaways

The fetal sleeping position is one of the most common sleep positions.
Many find the fetal position comfortable and that it can help alleviate snoring.
This position may not be suitable for those with back pain, a shoulder injury, or people who are pregnant.

There is no one-size-fits-all approach when it comes to sleeping positions. Some people find sleeping on their backs to be the most comfortable, while others find stomach sleeping to be the best position for their bodies. Body positioning during sleep should be chosen based on what feels most comfortable to you.

Researchers often divide sleep positions into three categories: back, stomach, and side sleeping Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source . Side sleeping is the most common, with sleepers spending 54% of each night on their sides, on average. Within each sleep position category, however, there are subtle variations. The fetal position, for example, is a specific form of side sleeping.

What Is the Fetal Sleep Position?

When you lie on your side and bring your knees up to your chest, you are sleeping in the fetal position. Some people curl an arm under their pillow to support their head while in this position, but others may not. It is called the fetal position because it mimics the position of a fetus in the womb.

Side sleeping is the most common sleep position, but researchers have not yet studied how many people curl up into the fetal position while sleeping on their sides. Sleeping on your side appears to become more preferable as you get older Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source . Children usually spend equal time sleeping on their stomachs, sides, and backs, while older adults spend more time asleep on their sides.

Benefits of the Fetal Sleep Position

Sleeping on your side offers quite a few benefits. Studies show that sleeping on your side may help reduce heartburn Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source , especially if you are sleeping on your left side. Snoring Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source , another common sleep disturbance, is also reduced when sleeping on your side. You may want to consider sleeping in the fetal position if you share a bed with a partner, in order to minimize sleep disturbances Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source and other issues caused by snoring.

Sleeping on your side might be a good option if you:

Are pregnant
Have heartburn or acid reflux
Experience back pain
Snore or have obstructive sleep apnea
Are older or have limited spinal mobility

Who Should Sleep in the Fetal Position?

Some people may benefit more from side sleeping than others. Pregnant people, those who have obstructive sleep apnea, and people experiencing back pain may enjoy the greatest benefits from side sleeping.

Pregnant People

Sleeping in the fetal position may be a great option for people who are pregnant, especially in the later stages of pregnancy. Sleeping on your back while pregnant can put unnecessary pressure Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source on your back and cardiac system.

The fetal position, in which you are sleeping on your side with your knees bent, can reduce pressure on your heart Trusted Source Medline Plus MedlinePlus is an online health information resource for patients and their families and friends. View Source during pregnancy. Experts specifically recommend sleeping on your left side while pregnant.

Specialized pregnancy pillows can help support your back and legs during sleep so you can more comfortably sleep on your side. You can also use extra pillows you have around the house. Placing them under your belly and between your legs may help reduce any additional tension and promote spinal alignment as you side sleep.

People With Obstructive Sleep Apnea

Obstructive sleep apnea is a sleep disorder that affects 2% to 9% Trusted Source MSD Manuals First published in 1899 as a small reference book for physicians and pharmacists, the Manual grew in size and scope to become one of the most widely used comprehensive medical resources for professionals and consumers. View Source of adults. Sleep apnea occurs when your airway becomes partially or fully blocked Trusted Source Medline Plus MedlinePlus is an online health information resource for patients and their families and friends. View Source during sleep, resulting in gasping or choking noises and snoring. Sleep apnea may cause daytime drowsiness and a lack of concentration, putting people who have the disorder at a higher risk for car crashes and other accidents.

Sleeping on your side can help reduce snoring Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source and may help prevent the blockages to your airway associated with obstructive sleep apnea. Studies have found that people with sleep apnea who sleep on their sides are less likely to experience disruptive breathing Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source during the night.

To help you sleep on your side throughout the night, you may want to try placing a pillow against your back to prevent you from rolling over.

People With Back Pain

Sleeping with back pain can be uncomfortable and discouraging. A reported 8 out of 10 people Trusted Source Medline Plus MedlinePlus is an online health information resource for patients and their families and friends. View Source experience back pain at some point during their life. If you experience back pain, you might wonder if your sleeping position impacts how much pain you experience.

Sleeping on your side, which includes in the fetal position, has been shown to reduce back pain Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source upon waking. When side sleeping, make sure your spine is aligned and there is no added pressure on your neck, which can cause neck pain. Sleeping with a pillow or rolled-up towel between your knees can help ensure that your spine is neutral and protected. You may also want to purchase a pillow specifically designed for side sleeping to protect your neck.

When to Consider Other Sleeping Positions

Sleeping in the fetal position may not be suitable for you if you have a shoulder injury or experience shoulder pain. Sleeping on your side can cause the shoulder to take on more pressure than usual. In a study of people who experience pain in only one shoulder, 67% were side sleepers Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source who slept on the painful shoulder. This high percentage suggests side sleeping can cause or exacerbate shoulder pain in some people. If you prefer sleeping in the fetal position and experience shoulder pain, regularly alternating between sleeping on your left and right sides can help take the pressure off one shoulder.

If you are concerned about developing wrinkles, then sleeping on your side might not be the best option for you. The fetal position presses one side of your face against your pillow, and research suggests sleeping with your face against the pillow can cause wrinkling Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source . Sleeping on your back may be preferable.

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Written By

Danielle Pacheco, Staff Writer

Danielle is originally from Vancouver, BC, where she has spent many hours staring at her ceiling trying to fall asleep. Danielle studied the science of sleep with a degree in psychology at the University of British Columbia

Medically Reviewed by

Dr. Anis Rehman, Internal Medicine Physician MD

Dr. Rehman, M.D., is a board-certified physician in Internal Medicine as well as Endocrinology, Diabetes, and Metabolism.

Learn more about our Editorial Team

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