You take your three-month-old over to grandma’s house for a visit, and as the loving grandma coddles and showers the baby with affection, you suddenly hear her say, “Oh my, what is wrong with her head?” Concerned, you inspect baby’s skull and are horrified to see that one side of the back of the head is extremely flat. You rush your funny-shaped-head baby to the doctor for an immediate evaluation. Relax. Your doctor has probably seen this a million times because it is a very normal occurrence in babies.
During the second or third month of life, some babies begin to develop a flat area on the back of the head. This is called positional plagiocephaly, and typically occurs either on one side or directly in the middle of the back of the head when a baby spends too much time sleeping with the head in one position. You can easily see this asymmetry by viewing your baby’s head from the top. The weight of baby’s head pressing down against the bed applies pressure to that area of the skull. This causes that area to flatten, and the opposite side to appear more pointed. As baby develops a flat spot, it becomes more comfortable for him to continue sleeping with his head resting on the flat area. This preference only makes the problem worse. The vicious cycle continues, and soon your baby’s has the funniest shaped head on the block.
You can prevent this from occurring in the first place by rotating your baby’s sleep position (always keeping baby on his back or side), making sure baby spends equal time on both sides. If your baby does develop a flat spot, use a wedge or rolled up blanket to prop baby on his side so the non-flat part of his head rests on the bed. For example, if the left side of baby’s head gets flat, prop him on his side facing to his right. During the day when you put baby down to play, place him so all the action is on the side opposite his flat spot. A few months of this should straighten out the problem, and your doctor will monitor baby’s progress. Do not worry, this flat area is purely a cosmetic issue, and has no effect on the baby’s brain growth. Do not rush to the doctor if you notice a flat area. It can wait until baby’s next check up.
There is an extremely rare condition where the skull bones don’t expand as baby’s brain grows, creating an asymmetric skull. Be sure your doctor examines baby’s skull carefully to make sure this is not the case. Severe cases of positional plagiocephaly can be treated using a pressure helmet which slowly molds baby’s head back into shape. These are expensive, and rarely necessary.