Baby sleeping on side

Side-sleeping may be a common practice for adults, but is it safe to put your baby to sleep on her side? Find out at what age babies can sleep on their sides, and why the back-sleeping position is recommended to reduce the risk of Sudden Infant Death Syndrome (SIDS).

Is It OK for Babies to Be Put to Sleep on Their Sides?

Babies younger than 12 months should not be put to sleep on their sides. Medical experts once believed that side-sleeping was OK for newborns and infants, but evidence has shown that this position isn’t as safe as back-sleeping. This is because side-sleeping may increase the risk of SIDS, especially in the first six months.

Why Shouldn’t Babies Sleep on Their Sides?

If your baby falls asleep on his side, he can easily end up rolling onto his stomach, a sleeping position that can block the airways and impair your baby’s breathing. Sleeping on the stomach may also increase the chance of your baby “rebreathing” the air she has already expelled, leading to a decline in oxygen levels and an increase in carbon dioxide. This can result in your baby not being able to wake herself up. Until your baby turns 1, be sure to place her to sleep on her back for every sleep, including naps.

What if Your Baby Rolls on His Side During Sleep?

If you notice your baby has shifted onto his side during sleep, gently roll him onto his back. Do this during the first year until your little one is able to roll over both ways by himself. Read more about when babies typically start learning to roll over by themselves.

How to Prevent Side-Sleeping in the First 12 Months

There’s no way to prevent your baby from rolling onto her side or stomach during sleep, but what you can do is ensure that you always put her down to sleep on her back. If she happens to roll onto her side or stomach, gently return her to her back. Keep doing this during the first year until you are confident your baby can roll herself over both ways without any difficulty.

Reducing the Risk of SIDS

There’s more you can do to reduce the risk of SIDS:

  • Put your baby to sleep on his back

  • Have him sleep in a crib with a firm crib mattress covered by a tight-fitting sheet

  • Keep the crib empty — no blankets, quilts, pillows, plush toys, or bumper pads.

When Can Babies Sleep on Their Sides?

After the age of 1, you can let your baby sleep on her side. However, it's important to always place your baby in his crib on his back onto a firm crib mattress that’s covered with a fitted sheet. In the first year, the crib shouldn’t contain any loose bedding, bumper pads, blankets, pillows, or stuffed animals. It should be completely empty.

The Bottom Line

During the first year of your little one's life, always place her on her back for every sleep. Back-sleeping is the safest sleeping position for your baby. Side-sleeping can increase the risk of SIDS. If your baby happens to roll onto his side or stomach during sleep, and is under 1 year old, gently return him to the back position. Continue to do this until your baby is able to comfortably roll herself over in both directions.