icon-arrow-down icon icon-arrow-fill-down icon icon-arrow-next icon icon-arrow-prev icon icon-tag-close icon
If baby sleeps on her back, will she develop a flat head?
Q: My mother and other relatives have told us to rotate our baby from her left side to her right so she develops a nice round head. She sleeps on her back at night, but we’ve noticed that she’s developing a flat head. Still, our doctor assures us that her head will have a normal shape! What’s the truth?
Nicole Las Vegas
A: Nicole, it’s good that you asked this question because it can be difficult to sort out different advice from family members, friends and health professionals.

In recent years, more babies have developed slightly flattened heads since parents are putting them to sleep on their backs to prevent SIDS. Babies’ skull bones are naturally soft and flexible, allowing them to squeeze through the birth canal during childbirth. Many babies born by vaginal delivery come out with slightly pointed heads. When a baby’s head rests for many hours against a hard surface such as a mattress, car seat or infant carrier, the skull can become flattened. Premature babies have softer skulls, which are even more prone to flattening.

Although it can be disturbing to see your baby’s misshapen head, this usually does not cause problems and usually resolves between 6 and 12 months of age, once they spend less time on their backs and more time sitting up and crawling.

The American Academy of Pediatrics has given recommendations for what parents can do to prevent head flattening in infants:
  • Always put your baby to sleep on her back, unless your doctor recommends a different position. Even though this might slightly increase the chance of head flattening, it is crucial to protect your baby from SIDS
  • .

  • Alternate your baby’s position in the cot each time you put him to sleep. One night, put her to sleep with her head at the head of the cot; the next night, with her head at the foot of the cot. Since babies naturally spend more time turning their heads toward the door (to look for you coming into the room) or the window (to see the light), this will give her practice turning her head equally in both directions.

  • Try to minimize the amount of time your baby spends in a car seat, baby carrier, swing or bouncy seat, which can also put pressure on the back of her head. Though your baby must always be in the car seat when you’re driving, think about times when you could walk instead of drive, and carry your baby in a front-pouch, sling, backpack or stroller. Also, when you’re at home, take your baby out of the seat and spend time holding and cuddling him.

  • Give your baby lots of supervised “tummy time” when she’s awake. Playing on her tummy helps take the pressure off the back of her head and also helps her strengthen her upper body, arms and neck.

  • Ask your baby’s doctor to check her head and neck at every well-baby visit. The doctor will tell you whether you need to be concerned or take any special measures. Usually an exam is sufficient, but if the doctor is concerned, she might order an X-ray or CT scan of your baby’s head. Follow your doctor’s recommendations:

    • If the cause of the flattening is positioning: the doctor would recommend that you follow the measures listed above. Some also recommend that you position your baby to lie more on the rounded side of her head. You could also move the cot to a different position in her room, requiring her to look away from the flattened side to see things of interest in the room. Rarely, if the deformity is severe and doesn’t improve, the doctor may refer you to a pediatric specialist who could advise whether a special skull-molding helmet or surgery would be helpful.

    • If the cause is neck/shoulder muscle spasm: some babies tend to keep their head turned to one side because of neck or shoulder muscle spasms (“torticollis”). For this condition, the doctor may advise you to stretch your baby’s neck muscles very gently at each nappy change: pointing the chin toward each shoulder, then each ear toward the shoulder. Each stretch is held for 10 seconds and the series is repeated three times. These exercises usually improve the problem within a few months. If the problem persists, the doctor may refer your baby to a physical therapist.

    • Very rarely, a baby’s skull plates fuse together prematurely, causing an abnormal skull shape. An X-ray or CT scan might be necessary to confirm this diagnosis. In this case, surgery would be necessary.
In all, remember that mild flattening of the head is common and usually resolves within the first year. If you’re still concerned, talk with your doctor. For more information, visit the website for the American Academy of Pediatrics at www.aap.org.

Karen Sokal-Gutierrez M.D., M.P.H. Pediatrician