Can Newborns Sleep on Their Side? A Pediatrician's Guide to Safe Sleep

Medically Reviewed by: Dr. Makia Powers, MD, FAAP | Blueberry Pediatrics

No — newborns should not sleep on their side. The American Academy of Pediatrics (AAP) says babies should always sleep on their backs. This goes for every nap and every bedtime, all the way until their first birthday. Side sleeping is risky because babies can more easily roll onto their tummies. This raises the chance of Sudden Infant Death Syndrome (SIDS). Each year, about 3,400 babies in the U.S. die from sudden sleep-related causes. Where and how your baby sleeps is the most important thing you can control.

This guide explains why back sleeping is safest, what to do if your baby rolls, and how to set up a safe sleep space.

Key Takeaways

• Always place your baby on their back for every sleep — naps and nighttime
• Side sleeping is not safe — it roughly doubles the risk of SIDS compared to back sleeping
• Once your baby can roll both ways on their own, you can let them find their own position
• Every caregiver needs to follow the same rules — grandparents, babysitters, and daycare
• A safe crib means a firm, flat mattress with nothing else in it
• Talk to your pediatrician if you have any concerns about your baby's sleep

Why Back Sleeping Is the Safest Position

Back sleeping is the single best thing you can do to lower your baby's risk of SIDS. The AAP's safe sleep guidelines — last updated in 2022 — are clear: babies should be placed on their backs for every sleep.

This isn't new advice. The "Back to Sleep" campaign started in 1994. Since then, SIDS rates have dropped by more than half. That's thousands of lives saved, all from one simple change in how we put babies to bed.

Doctors now call it the "Safe to Sleep" campaign. The message is the same: back is best, every single time.

Why Side Sleeping Is Risky for Newborns

Side sleeping might seem like a safe middle ground between back and stomach, but it's not. Here's why:

• It's an unstable position. Babies placed on their sides can more easily roll onto their stomachs. Once face-down, a young baby may not be able to lift or turn their head to breathe.
• It raises the risk. Research shows that side sleeping roughly doubles the risk of SIDS compared to back sleeping. That's a big difference for something that's easy to prevent.
• An unfamiliar sleep position is especially dangerous. If your baby usually sleeps on their back but gets placed on their side or tummy — say, at a grandparent's house or a new daycare — the risk goes up dramatically. Babies who aren't used to a different sleep position are the most vulnerable.

That's why it's so important that every person who puts your baby down to sleep follows the same rule: always on the back. Talk to grandparents, babysitters, and daycare providers. Make sure everyone is on the same page.

What If Your Newborn Rolls to Their Side?

It's normal to worry when your baby starts moving around in the crib. Here's what you need to know:

• If your baby can only roll one way (back to tummy, but not tummy to back), gently turn them onto their back.
• If your baby can roll both ways — back to tummy and tummy to back — you can let them stay in whatever position they choose. This usually happens around 4 to 6 months.
• Always start on the back. Even after your baby can roll, always place them on their back to begin every sleep.
• Never use wedges or positioners. These products are not safe. They can block your baby's airway and cause suffocation.
• Skip the rolled-up towels, too. Homemade fixes are just as risky as store-bought positioners.

When Can Babies Safely Sleep on Their Stomach?

Once your baby can roll both ways on their own, they've shown they have the strength and coordination to move if they need to breathe. At that point, you don't need to keep flipping them back over during the night.

Most babies reach this milestone between 4 and 6 months, but every baby is different. Some get there earlier, some later. Keep placing your baby on their back to start every sleep through their first birthday — and let them roll on their own from there.

Will Back Sleeping Cause a Flat Head?

You may have heard that back sleeping can give babies a flat spot on their head. Doctors call this positional plagiocephaly. It's very common — close to half of babies develop a mild flat spot in the first few months.

Here's the good news: it almost always gets better on its own by 12 months. And here's the most important part: a flat spot is never a reason to stop back sleeping. The risk of SIDS is a far more serious concern.

How to Prevent Flat Spots

• Switch the direction your baby's head faces each night
• Do tummy time every day when your baby is awake and you're watching — aim for at least 30 minutes a day by 3 months, starting with short sessions from the first days of life
• Change up how you hold and carry your baby throughout the day
• Limit time in car seats, bouncers, and swings when you're not traveling
• Move the crib or change which end your baby's head is at, so they look toward activity from different sides

If you notice a flat spot that's getting worse, or your baby has trouble turning their head in one direction, talk to your pediatrician. In most cases, simple stretching exercises help. Rarely, a baby may need a special helmet — your doctor will let you know.

Creating a Safe Sleep Space

A safe crib setup is just as important as sleep position. Follow the ABCs of safe sleep:

• Alone — your baby should sleep Alone, in their own space, not in your bed
• Back — always on their back
• Crib — a flat, firm surface made for infant sleep, like a Crib or a bassinet

Here's your safe sleep checklist:

• Use a firm, flat mattress that fits snugly in the crib — no gaps around the edges
• Keep the crib empty — no blankets, pillows, bumpers, or stuffed animals
• Use a sleep sack or wearable blanket instead of loose bedding
• Keep the room at a comfortable temperature — dress your baby in one extra layer compared to what you'd wear
• Share your room (but not your bed) for at least the first 6 months
• Offer a pacifier at nap time and bedtime — studies show this can cut SIDS risk by about half
• Don't smoke around your baby — before or after birth
• Breastfeed if you can — it helps protect against SIDS
• Skip the fancy gadgets — monitors, positioners, and inclined sleepers marketed to prevent SIDS aren't proven to work, and some are dangerous
• Avoid using car seats, strollers, and swings for routine sleep — these are for travel, not sleeping

Swaddles and Safe Sleep

Swaddling can help calm a fussy newborn, but you need to stop as soon as your baby starts trying to roll. This can happen as early as 2 months old.

Why is this so urgent? A swaddled baby who rolls face-down can't use their arms to push up or turn their head. That's a serious suffocation risk. When it's time to stop swaddling, switch to a sleep sack that leaves your baby's arms free.

Signs it's time to stop swaddling:

• Your baby is trying to roll over
• Your baby is breaking out of the swaddle
• Your baby is around 2 months old (even if they haven't rolled yet — better safe than sorry)

Common Myths About Newborn Sleep Positions

Myth: Inclined surfaces help babies with reflux sleep safely.
Truth: The AAP does not recommend inclined sleep surfaces — even for babies with reflux. Inclines can cause babies to slide into positions that block their airway. Products like the Fisher-Price Rock 'n Play were recalled after being linked to infant deaths.

Myth: Side sleeping helps with gas and colic.
Truth: There's no evidence that side sleeping eases gas or colic. For a gassy baby, try gentle tummy massage, bicycle legs, or supervised tummy time — all while your baby is awake and you're watching.

Myth: Babies will choke on spit-up if they sleep on their back.
Truth: Babies have natural reflexes that protect their airway. Back sleeping does not increase the risk of choking — even for babies with reflux. Choking rates have not gone up since the Back to Sleep campaign started in 1994 — but SIDS rates have gone dramatically down.

Frequently Asked Questions

Is it safe for newborns to sleep on their side?

No. The AAP says all babies should sleep on their backs until age 1. Side sleeping is not safe because babies can roll onto their stomachs, which raises the risk of SIDS.

What if my baby keeps rolling to their side?

If your baby can only roll one way, gently put them back on their back. Once they can roll both directions on their own, it's okay to let them settle into their own position. Always start them on their back.

When can my baby sleep on their stomach?

Once your baby can roll both ways on their own — usually between 4 and 6 months. Always place them on their back to start, and let them roll if they want to.

Should I worry if my newborn sleeps with their head to one side?

Some head turning is normal. But if your baby always turns the same way or you notice a flat spot getting worse, talk to your pediatrician. Tummy time and changing positions during the day usually help.

When should I stop swaddling my baby?

Stop swaddling at the first sign of rolling — this can happen as early as 2 months. Switch to a sleep sack that leaves your baby's arms free.

When to Contact Your Pediatrician

Most of the time, following safe sleep guidelines is all you need to keep your baby safe. But reach out to your pediatrician if:

• Your baby has trouble breathing during sleep — pauses, gasping, or noisy breathing
• You notice a flat spot getting worse or your baby tilts their head to one side
• Your baby can't seem to sleep on their back despite your best efforts
• You're worried about reflux or spit-up during sleep
• Your baby was born early or has a health condition that might affect sleep
• You're not sure if your baby's movements count as real rolling

At Blueberry Pediatrics, our board-certified pediatricians are here to help with your safe sleep questions — day or night. If you're ever worried about how your baby is sleeping, you can chat with a Blueberry pediatrician in minutes.

Sources

• American Academy of Pediatrics. (2022). Sleep-Related Infant Deaths: Updated 2022 Recommendations for Reducing Infant Deaths in the Sleep Environment. Pediatrics, 150(1).
• Moon, R. Y., & Task Force on Sudden Infant Death Syndrome. (2016). SIDS and Other Sleep-Related Infant Deaths: Evidence Base for 2016 Updated Recommendations for a Safe Infant Sleeping Environment. Pediatrics, 138(5).
• Priyadarshi, M., et al. (2022). Non-supine sleep position and risk of SIDS: A systematic review and meta-analysis. European Journal of Pediatrics.
• CDC. (2023). Data and Statistics for SIDS and SUID.