When Can Babies Sleep on Their Stomach?

We all have our favorite sleep position—the one that makes us feel cozy and safe and guarantees we’ll be fast asleep before we even count a single sheep. While some of us like to be the big spoon to our pillows, others prefer to lie on our backs and starfish across the entire bed. What about your baby? If you notice your little one struggling to fall asleep on her back, you may wonder, when can babies sleep on their stomachs? 

According to the American Academy of Pediatrics (AAP), you should continue to place your baby on her back to sleep until she’s 1 year old. However, once your baby has developed the motor skills to roll over on her own, you don’t need to worry if she rolls onto her stomach to sleep in her favorite position.  

The Risks of Early Stomach Sleeping 

Why the wait when it comes to infant stomach sleeping? It’s not advised for babies to sleep on their belly because it isn’t safe. For infants, stomach sleeping significantly increases the risk of sudden infant death syndrome (SIDS). In fact, SIDS is the leading cause of death in children younger than 1-year-old, peaking between 2 and 4 months. 

While the exact correlation between stomach sleeping and SIDS isn’t known, researchers believe the following factors come into play: 

• Carbon dioxide build-up – Stomach sleeping can cause your baby to breathe in his own exhaled breath, increasing the risk of hypercapnia—the build-up of carbon dioxide in the body—and hypoxia—the decrease of oxygen in body tissues. 
• Overheating – In addition to increasing carbon dioxide levels, inhaling exhaled breath can prevent body heat from escaping, which can cause your little snoozer to overheat during sleep. 
• Decreased blood pressure – While further research is needed, some studies have found that stomach sleeping lowers blood pressure, which can disrupt the healthy rate of blood flow to your baby’s organs and brain. 
• Lowered heart rate – By decreasing your baby’s blood pressure, stomach sleeping can also lower his heart rate. 
• Suffocation – If a baby sleeping on his stomach hasn’t yet developed the strength and motor skills to lift his head and neck on his own, he’s at an increased risk of accidental suffocation on his crib mattress. 

Regardless of the exact connection between stomach sleeping and SIDS, the rate of SIDS decreased by 50% between 1994 and 1999, when the rate of placing infants on their backs to sleep doubled. This statistic is why the AAP has maintained that “back is best” for infant sleeping. So, for those wondering if a baby sleeping on their back is safe, now you know!

The Best Sleep Position for Babies 

Since 1992, the AAP has recommended back sleeping as the safest sleeping position for babies younger than 1-year-old. Not only does back sleeping significantly lower the risk of SIDS, but a 2003 study also found that back sleeping reduced instances of infant:

• Ear infections  
• Stuffy noses 
• Fever 

While researchers aren’t sure why back sleeping reduces the likelihood of these medical conditions, some speculate that it may be because stomach sleeping causes higher airway temperatures, which create the type of hot, moist environment bacteria love to thrive in. 

It’s also thought that those who sleep on their backs swallow more frequently during sleep than those who sleep on their stomachs, which leads to more effective clearing of the eustachian tubes—tiny passageways that connect the middle ear to the throat and allow fluid to drain from the ears. When fluid isn’t effectively cleared from these passageways, ear infections are more likely to occur. 

When Stomach Sleeping Becomes Safe 

The AAP recommends placing your baby on her back to sleep for at least the first year of her life. What if your little dreamer insists on sleeping on her stomach by rolling herself over while she’s in her crib? Fortunately, you don’t have to stay up all night flipping your baby over like an adorable little pancake. 

If your baby has developed the motor skills and strength to lift her head on her own and roll herself from her back to her stomach and back again, she’s safe to sleep on her stomach. Because she’s developed these skills, she’ll be able to roll herself into a different position or lift her head if she needs to. 

If, on the other hand, your baby hasn’t developed the motor skills to roll over on her own, it’s important that she remains on her back during sleep. 

How to Help Promote Stomach-Free Snoozing 

Like those of us who love to lie across the entirety of our beds, some babies naturally prefer to sleep on their stomachs. This may be because stomach sleeping places pressure on the chest and promotes the same type of coziness and warmth your baby felt inside mom’s womb. 

However, until your baby is over 1-year-old, he shouldn’t be placed to sleep on his stomach, no matter how much he whines and cries when put to sleep on his back. Although you can’t explain to your little one that back sleeping is best for his safety, you can do something to convince him to fall asleep in that position—make him as comfortable as possible. 

Developing sleep habits early can help your baby sleep consistently. But for him to have safe sleep, it’s also important to ensure you promote safe sleep practices. The following baby sleep tips can promote comfort, warmth, and coziness to help ease your baby into sleep, even when he’s placed on his back: 

• Swaddle your baby – Here is safe infant sleep tip number one: Until your baby is 4 to 6 months old, a swaddle can provide snugness and security similar to what he felt while living peacefully inside mom’s womb. The all-over pressure and warmth of the swaddle can help ease your baby into a restful slumber when he’s placed on his back. 
• Set the right temperature – While the warmth of a swaddle or a sleep sack can make back-sleeping cozier, too much heat can make your baby uncomfortable. For the ideal sleep environment, set your thermostat to between 68 and 72 degrees Fahrenheit. 
• Re-create the sounds of the womb – The white noise produced by sound machines doesn’t just drown out the ambient sounds of your home—it also mimics the whooshing your baby heard when nestled safely in the womb. If we’ve learned anything from years of falling asleep to Friends reruns, it’s that comforting, nostalgic sounds can lull anyone to sleep. 
• Invest in black-out curtains – If your fussy stomach sleeper is having a hard time winding down for a nap, try using black-out curtains in the baby’s sleep area to keep daytime light from permeating his womb-like bedroom environment. Darkness, particularly the absence of blue light, signals to our brains that it’s nighttime, which prompts the production of melatonin—the sleep hormone. 
• Stick to a consistent routine – Consider following the same routine every time you lie your baby down for sleep. Over time, this routine will signal to your baby’s brain that it’s bedtime and kickstart his body’s production of melatonin, which will help him fall asleep no matter what position he’s in. Your routine can include: 
  • Giving him a warm bath 
  • Singing him a lullaby 
  • Reading him a story 
  • Rocking him gently  

Other Safe Sleeping Recommendations 

Stomach sleeping isn’t the only factor that can increase the risk of SIDS. To further ensure your baby’s safety during her trips to dreamland, consider the following safe sleeping recommendations: 

• Use a firm mattress – Soft mattresses that your baby sinks into increase her likelihood of accidentally rolling onto her side during sleep. When a baby is sleeping on his side, it’s much easier for her to accidentally roll onto her stomach. 
• Don’t place other items in the crib – While you may think a few snuggly stuffed animals will make for the ultimate sleep companions, anything you put in your baby’s crib can pose a choking or suffocation hazard. So avoid adding toys, blankets, pillows, and even sleep bumpers to your baby’s crib. Probably the only exception to this would be a sleep positioner or two just to prevent your baby from rolling over on his stomach or to the side.
• Close the gaps – Gaps between your baby’s mattress and the crib should be no more than two fingers thick. This ensures your baby won’t get her head, arms, or legs stuck between the crib and mattress, which can increase the risk of suffocation. 
• Choose the right crib – It’s best to not use modified cribs, or models that are over 10 years old, as their structural integrity may be compromised. 

Babies can safely sleep on their stomachs once they have developed the necessary motor skills to roll over on their own, generally around 1-year-old, but maintaining a ‘back is best’ approach significantly reduces risks associated with SIDS and other health concerns. By incorporating safe sleep practices such as swaddling, setting a suitable room temperature, using white noise, and maintaining a consistent routine, parents can ensure that their little ones are both comfortable and safe, even if they show a natural inclination towards stomach sleeping.

If you still have questions like “what is the best sleep position for a congested baby”,  “what is the best sleep position for a gassy baby” or “what is the best sleep position for a colic baby”, read our linked blogs!

Editorial Policy

At SneakPeek, our commitment is to provide accurate, up-to-date, and reliable information to empower our readers. Our content is thoroughly researched, reviewed by medical experts, and fact-checked to ensure its credibility. We prioritize the well-being and education of our readers, and our editorial policy adheres to the highest standards of integrity and accuracy in all our articles.

This post has been reviewed for accuracy by:

Sarah Cacia

Sarah Cacia, currently leading as the Director of Business Development at Gateway Genomics, parent company of SneakPeek, brings an impressive blend of bioengineering expertise and clinical business acumen. Her extensive experience, marked by roles at renowned institutions like Genentech and UC San Diego's Cardiac Mechanics Research Group, underpins her deep understanding of biotechnology and clinical research. A UC San Diego alumna with a Bachelor of Science in Bioengineering: BioSystems, Sarah's rich professional background empowers her to provide authoritative insights into the cutting-edge developments in the field.

Sources:

1. Healthline. When Can Babies Sleep on Their Stomach Safely? https://www.healthline.com/health/baby/baby-sleeping-on-stomach#how-long-to-follow-guidelines
2. NIH Safe to Sleep. Fast Facts About SIDS.  https://safetosleep.nichd.nih.gov/safesleepbasics/SIDS/fastfacts 
3. NIH Safe to Sleep. Research on Back Sleeping And SIDS. https://safetosleep.nichd.nih.gov/research/science/backsleeping#:~:text=The%20simple%20act%20of%20placing,to%20SIDS%20risk%20has%20increased.
4. NCBI. SIDS Sudden Infant and Early Childhood Death: The Past, the Present and the Future. https://www.ncbi.nlm.nih.gov/books/NBK513399/ 
5. Web MD. Sleep Face Down for Lower Blood Pressure. https://www.webmd.com/hypertension-high-blood-pressure/news/20041011/sleep-face-down-for-lower-blood-pressure
6. Drugs.com. Hypotension in Infants. https://www.drugs.com/cg/hypotension-in-infants.html#:~:text=Without%20treatment%2C%20hypotension%20can%20decrease,treated%20may%20be%20life-threatening. 
7. NIH Safe to Sleep. Progress in Reducing SIDS. https://safetosleep.nichd.nih.gov/activities/SIDS/progress 
8. Kids Health. Sleep and Your 4- to 7-Month-Old. https://kidshealth.org/en/parents/sleep47m.html#:~:text=Always%20place%20your%20baby%20on,the%20sleep%20position%20they%20choose. 
9. JAMA Network. Infant Sleep Position and Associated Health Outcomes. https://jamanetwork.com/journals/jamapediatrics/fullarticle/481332 
10. Healthline. When Should I Stop Swaddling My Baby? https://www.healthline.com/health/parenting/when-to-stop-swaddling#TOC_TITLE_HDR_1 
11. WebMD. What’s the Right Room Temperature for a Baby? https://www.webmd.com/baby/what-is-the-right-room-temperature-for-a-baby#1 
12. UMPC. Crib Safety. https://www.chp.edu/injury-prevention/teachers-and-parents/safety-handbook/before-you-bring-your-baby-home/crib#:~:text=The%20mattress%20should%20fit%20the,and%20sides%20of%20the%20crib
13. The Baby Sleep Site. When To Stop Swaddling Your Baby and 3 Ways to Transition. https://www.babysleepsite.com/sleep-training/how-when-to-stop-swaddling-baby/