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  • Current: Preventing flat heads in babies who sleep on their…

Preventing flat heads in babies who sleep on their backs

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Why do some babies develop flat spots on their heads?

For the first 6 months, the safest place for your baby to sleep is on their back, in a crib in your room. Babies who sleep on their back are much less likely to die of sudden infant death syndrome (SIDS). SIDS is when a baby (less than 1 year old), that seems healthy dies suddenly in their sleep, and the cause of death cannot be explained.

A baby’s skull is very soft and the bones can be affected by pressure. Babies also have weak neck muscles and usually turn their heads to one side when placed on their back. Because of this, your baby’s skull may flatten. This is known as a “flat head.” The medical term for this is positional plagiocephaly.

A little bit of flattening goes away on its own. More serious flattening may not completely go away, but it will not affect a baby’s brain or development.

Can flat head be prevented?

Most can be prevented. However, it is not always completely preventable. Even by using the sleep positioning described below, some babies will develop flat parts on the back of their heads.

A simple way to help prevent your baby from getting a flat head is to change their position in the crib each day. Because your baby likes to have something interesting to look at, they might turn their head to look at their room rather than toward the wall when in their crib. This way they can also see you come and go.

Here’s how you change your baby’s head position while still giving them the same “view” from their crib:

  • One day, place your baby with their head toward the head of the crib.
  • The next day, place your baby with their head toward the foot of the crib.
  • Alternate your baby’s position every day.

You can also try putting a mobile on the side of the crib facing the room to encourage your baby to look that way.

What else can I do to prevent my baby from getting a flat head? 

Babies should also have supervised “tummy time” when they are awake, for 10 to 15 minutes, and at least 3 times a day. This means you set your baby down to play on their tummy. Not only does tummy time help prevent a flat spot on the head, it is important for your baby’s overall physical development.

When should I call a doctor?

If your baby still develops flat spots, talk to your child's doctor.

More information from the CPS

  • Safe sleep for babies

Additional resources

  • Joint statement on Safe Sleep (Public Health Agency of Canada)

Reviewed by the following CPS committees

  • Community Paediatrics Committee

Last updated: March 2022

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