No, side sleeping is not safe for newborns. The only recommended sleep position for babies is flat on their back, for every sleep, until they can roll over on their own. Side sleeping carries a higher risk of sudden infant death syndrome (SIDS) because babies can easily roll from their side onto their stomach, where the risk of suffocation increases significantly.
Why Back Sleeping Is Safer
The reason comes down to simple anatomy and gravity. When a baby sleeps on their back, the windpipe (the tube to the lungs) sits on top of the esophagus (the tube to the stomach). If your baby spits up, any fluid has to travel upward against gravity to reach the airway, which makes choking very unlikely. Babies also have a natural gag reflex that causes them to cough up or swallow any fluid automatically.
When a baby is on their stomach, that arrangement flips. The opening to the stomach sits above the opening to the lungs, so spit-up can pool right at the airway entrance. Side sleeping is unstable for newborns, who lack the muscle control to stay in that position. A baby placed on their side can easily roll onto their stomach without the strength to lift their head or reposition themselves.
Back sleeping became the standard recommendation in the 1990s, and the rate of sleep-related infant deaths dropped significantly afterward.
What About Babies With Reflux?
This is one of the most common reasons parents consider side sleeping. It feels intuitive that a baby who spits up frequently would be safer on their side. But the medical evidence says otherwise. Back sleeping remains the safest position even for babies with reflux, and this position is supported not just by the American Academy of Pediatrics but also by gastroenterology organizations in both North America and Europe that specialize in digestive issues in children.
Healthy babies placed on their backs are not more likely to have serious or fatal choking episodes than those placed on their stomachs. The gag reflex handles spit-up effectively in the back position. Elevating the head of the crib doesn’t help with reflux either, and it creates a new danger: the baby can slide to the foot of the bed or shift into a position that blocks their breathing.
Sleep Positioners and Wedges Are Dangerous
You may have seen products marketed as “anti-roll” pillows, sleep wedges, or positioners that claim to keep your baby on their side or back. Do not use them. The U.S. Consumer Product Safety Commission and the FDA issued a joint warning telling parents to stop using infant sleep positioners after at least 12 infants between 1 and 4 months old suffocated in or around these devices.
The FDA has never cleared any sleep positioner for preventing SIDS. No scientific studies have demonstrated that these products reduce the risk of SIDS, suffocation, or any other life-threatening event. The AAP does not support their use either. The same goes for products marketed to help with reflux or flat head syndrome. Federal regulators have concluded that any potential benefit is outweighed by the suffocation risk.
When Your Baby Rolls to the Side on Their Own
Many parents notice their newborn scooting or tilting onto their side shortly after being placed on their back. In early infancy, this is uncommon for babies consistently placed on their backs, but it does happen. If your baby hasn’t yet developed the ability to roll both ways intentionally, the safest response is to gently turn them back onto their back. A pacifier or some quiet shushing can help them resettle.
Once your baby can roll over on their own, both from back to front and front to back, you no longer need to reposition them. There is no evidence that babies who roll independently need to be flipped back. At that point, the muscle control required to roll also means they have enough strength to shift their head and maintain an open airway. Continue placing them on their back at the start of every sleep, but let them find their own position after that.
This rolling phase can be frustrating because some babies get stuck on their stomachs before they’ve mastered rolling both directions. It typically lasts only a few weeks as they build coordination.
Stop Swaddling Once Rolling Starts
If your baby shows any signs of rolling, including rolling to their side, it’s time to stop swaddling. A swaddle restricts your baby’s arms, which means if they roll onto their stomach or side, they can’t push up or reposition themselves to keep their airway clear. Switch to a sleep sack instead, which keeps them warm but leaves their arms and hands free.
Along with ditching the swaddle, make sure the sleep space stays completely clear. No pillows, blankets, stuffed animals, bumper pads, or loose bedding. A firm, flat mattress with a fitted sheet is all your baby needs. The emptier the crib, the safer it is.