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The Boston Globe

Health & wellness

MD Mama

How to prevent, or deal with, flat spot on baby’s head

Adapted from the MD Mama blog on Boston.com.

The good news first: Since 1994, when the American Academy of Pediatrics (AAP) started recommending that all babies sleep on their backs, the rate of Sudden Infant Death Syndrome (SIDS) has dropped by 50 percent. That’s a lot of lives saved.

The bad news, which in comparison to that doesn’t seem like a big deal: More babies are getting flat spots on their heads from lying on their backs. In fact, in a study just released, researchers in Canada found that almost half of the 2-month-olds they examined had some of this flattening, called positional plagiocephaly.

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The skulls of babies are actually not one bone but lots of them held together by cartilage. This allows the head to squeeze through the birth canal, and for the rapid brain growth we see in infancy. The fact that there are many bones and that those bones are so able to adapt to change means that they are likely to be affected by position — and end up with flat spots when babies lie in the same position a lot.

Luckily, these flat spots don’t cause any damage to the brain and most go away once babies are older and not laying down so much. They can sometimes be permanent, and leave a child with an odd-shaped head, which could lead to teasing or self-esteem problems. If the flattening is severe, we sometimes fit babies for soft helmets that help the head grow rounder.

The best way to prevent the flat spots from happening is to change the position of your baby’s head regularly, so that he isn’t spending 24 hours a day with pressure on the same part of the skull. Here are three suggestions for doing this:

1. “Tummy time.” Having your baby spend time on his tummy is also good for building strength in the neck, trunk and arm muscles. So when he’s awake and you’re watching, put him on his belly. Many parents tell me their babies don’t like this, that they fuss and so the parents end up giving up after a couple of minutes and putting the baby on his back. You can help this by putting fun things to look at in front of the baby (like a baby mirror — babies love those), but the best thing to put in front is you. Get down on the floor too, on your belly, face-to-face with your baby. Or put baby on your chest.

2. “Wear” your baby, in a sling or other carrier. This can take pressure off the head.

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3. Vary the direction your baby’s head is facing when he is on his back. Because of the way they usually hang out in the birth canal as they drop down at the end of pregnancy, babies have a tendency to turn toward the right. When you lay baby down to sleep, alternate sides. If you have a baby that likes to turn to the right, during the day, position him so that interesting stuff to look at (like you) is on the left.

If you think your baby has a flat spot, mention it to your pediatrician. Together you can decide if a referral to a specialist is a good idea; usually, it’s not necessary.

Whatever you do, don’t put your baby on his belly to sleep. We can do something about a flat spot. We can’t do anything if a baby dies of SIDS.

Read more of this blog at Boston.com/MDMama.

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