The single most effective thing you can do to lower your baby’s risk of sudden unexpected infant death (SUID) is to place your sweet nugget on their back for all naps and nights, according to the National Institutes of Health. Despite sleep experts and pediatricians shouting this from the rooftops for more than 20 years, research shows that only about 44% of moms surveyed always follow this gold-standard sleep advice. Part of the reason for eschewing this recommendation:

Some parents think sleeping on your tummy is simply more comfortable for Baby. They believe that their baby prefers sleeping in their stomach. The thing is, when it comes to sleep safety, there’s way more to consider than your baby’s perceived coziness. To help parents understand why back-sleeping is always preferred to sleeping on your tummy, we answer your most-asked questions on babies and belly snoozing.

Why is sleeping on your stomach dangerous for babies?

The truth is, experts don’t yet entirely understand why sleeping on your tummy can lead to SUID. Stomach sleeping is thought to obstruct a baby’s airway and interfere with their little body’s ability to distribute heat, leading to overheating, which is another cause of SUID. Perhaps most importantly, research suggests that babies who snooze on their tummies may be “rebreathing” their own exhaled breath, which can lead to a rise in carbon dioxide and a drop in oxygen in the body. Normally, if a baby is taking in so-called “stale air,” their brain would trigger them to wake and cry to take in fresh oxygen. However, some babies may have a problem with the part of their brain that fires this wake-and-breathe signal.

I was put to sleep on my stomach when I was a baby. Was that wrong? 

Your parents were simply following the best advice available to them...and times have changed! Today, research shows that sleeping on your tummy puts babies at an increased risk for SUID. The sad and sobering fact is almost 49% of infants who die in their sleep are discovered on their tummies. But placing little ones on their backs for all sleeps greatly lowers their risk of infant sleep death. To wit: Since the start of the national Back to Sleep (now dubbed Safe to Sleep) campaign, the SUID rate in the United States has dropped by more than 50%.

I put my baby on her back to sleep, but my in-laws tend to put her on her tummy. Can babies sleep on their stomach sometimes?

Unfortunately, no. Babies who usually sleep on their backs, but are occasionally placed on their tummies for a nap or a nighttime sleep are actually at very high risk for SUID. It’s extremely important that everyone who cares for your baby—a partner, grandparents, babysitters, daycare workers—always place them on their back for all their sleeps to reduce their risk of sleep death.

Does sleeping on the stomach prevent choking in babies with reflux?

No! Even babies with reflux should sleep on their backs, notes the American Academy of Pediatrics (AAP). While vomiting and spitting up can be scary, rest assured that placing your baby on their back to go to sleep is not associated with choking. While back-sleeping, your baby’s airway anatomy and gag reflex work to keep them safe. When tummy-sleeping, however, babies are more likely to aspirate or choke, since anything they spit-up in this position can pool at the opening of their trachea.

What if my baby is most comfortable sleeping on their stomach?

Sleeping on your tummy can be super-comfortable for lots of babies...but that doesn’t make it safe. Indeed, it’s thought that some infants sleep so soundly on their bellies that it can make it markedly more difficult for them to easily wake when their breathing enters a danger zone. The best way to keep your baby comfortable and rested is to tap their innate calming reflex, which is a neurological response that’s, essentially, nature’s “off switch” for fussing. You can do this with a combo of swaddling, shushing, and rocking, all of which mimic the calming sensations of the womb.

Since it’s impossible to continuously rock and shush your swaddled snoozer all night, consider getting help from the award-winning SNOO Smart Sleeper. Our smart bassinet is designed to lull babies to dreamland—and soothe fussiness—with all-night responsive motion and sound. Plus, SNOO is the only baby bed with a secure swaddling system, keeping little ones snug and safe by preventing them from rolling to dangerous positions while sleeping. In fact, it's this innovation that earned SNOO FDA De Novo Authorization (For important safety information visit

What do I do if Baby rolls to stomach while sleeping?

Generally, by the time your baby can continuously roll all by themselves from front to back and then back to front, their chance of SUID is drastically reduced. That means you can likely leave your baby on their tummy if they roll while sleeping. However, if your wee one is not an expert roller, you should continue to reposition your baby onto their back post-roll. And whether your older baby rolls to their belly or not, it’s important to continue to initially place them on their back at bedtime and nap-time until their first birthday.

How can I make sure my baby stays on their back during sleep?

If you continue to place your little one on their back for all naps and night sleeps, they will grow accustomed to it and be more likely to remain there. For additional help ensuring your little one stays safely on their back during sleep, know that SNOO is the only bassinet that features a secure swaddling system, which helps prevent sleepyheads from rolling to unsafe positions. 

When can babies sleep on their stomach?

The most straight-forward answer is this: Once your baby reaches 12 months old, feel free to let them snooze on their belly if that’s what they prefer. (The AAP recommends back-sleeping for your baby’s first year.) A more nuanced answer: If Baby rolls to tummy while sleeping—and rolls back again with ease—it’s generally okay to let them shift into a stomach-sleeping position during sleep. This often occurs when your little one reaches about 6 months old. The key, however, is that your baby has to have completely mastered this skill first. And even if they have, it’s still important to continue to put your baby to bed on their back (on a flat and firm sleep surface) for the entirety of their first year.


For even more intel on getting babies and toddlers to sleep and stay asleep….and to love sleep, check out our baby and toddler sleep guides. 

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Disclaimer: The information on our site is NOT medical advice for any specific person or condition. It is only meant as general information. If you have any medical questions and concerns about your child or yourself, please contact your health provider.