A baby's head is easily molded. Know why and how to care for flat spots.

By Mayo Clinic Staff

Many newborns have slightly uneven heads. But is it cause for worry? Understand what causes unevenness in babies' heads and when treatment is needed.

Sometimes a baby's head is molded unevenly while passing through the birth canal. In other cases, head shape changes after birth as a result of pressure on the back of the head when the baby lies on his or her back.

You'll notice two soft areas at the top of your baby's head where the skull bones haven't yet grown together. These spots, called fontanels, allow a baby's relatively large head to move through the narrow birth canal. They also accommodate your baby's rapidly growing brain during infancy.

Because your baby's skull is malleable, however, a tendency to rest the head in the same position can result in an uneven head shape well past the time when birth-related lopsidedness evens out. This is known as positional plagiocephaly.

Your baby's doctor will check the soft spots on your baby's head and the shape of your baby's head at birth and at each well-baby exam — usually every two to four months for the first year.

Positional molding might be most noticeable when you're looking at your baby's head from above. From that view, the back of your baby's head might look flatter on one side than on the other. The cheekbone on the flat side might protrude, and the ear on the flat side might look pushed forward.

Your baby's head shape will most likely even out on its own. Positional molding is generally considered a cosmetic issue. Flat spots related to pressure on the back of the head don't cause brain damage or interfere with a baby's growth and development.

Keep in mind that if you spend too much time worrying about your baby's head shape, you might miss some of the fun of being a new parent. In a few short months, better head and neck control will help your baby keep pressure more evenly distributed on the skull.

Your baby's head shape will most likely even out on its own. But changes in the way you position your baby can minimize unevenness and hasten its resolution. For example:

  • Change direction. Continue to place your baby on his or her back to sleep, but alternate the direction your baby's head faces when you place him or her in the crib. Or place your baby's head near the foot of the crib one day, the head of the crib the next. You might also hold your baby with alternate arms at each feeding. If your baby returns to the original position while sleeping, adjust his or her position next time.
  • Hold your baby. Holding your baby when he or she is awake will help relieve pressure on your baby's head from swings, carriers and infant seats.
  • Try tummy time. With close supervision, place your baby on his or her tummy to play. Make sure the surface is firm.
  • Get creative. Position your baby so that he or she will have to turn away from the flattened side of the head to look at you or to track movement or sound in the room. Move the crib occasionally to give your baby a new vantage point. Never rest your baby's head on a pillow or other type of soft bedding.

If unevenness doesn't improve by age 4 months, your baby's doctor might prescribe a molded helmet to help shape your baby's head. The helmet provides guided growth, maintaining contact with the baby's head in all areas except for the flat spot.

Molded helmets are most effective when treatment begins by ages 4 to 6 months, when the skull is still malleable and the brain is growing rapidly. To be effective, the helmet must be worn 23 hours a day during the treatment period — often a number of months. The helmet is adjusted regularly — sometimes weekly — as the baby's head grows and changes shape. Treatment with a molded helmet isn't likely to be effective after age 1, when the skull bones are fused together and head growth becomes less rapid.

Recent research, however, suggests that repositioning with or without physical therapy might be as effective as helmet therapy in many cases.

Sometimes an underlying muscular issue — such as torticollis — causes a baby to hold his or her head tilted to one side. In this case, physical therapy is important to help stretch the affected muscles and allow the baby to more freely change head positions.

Rarely, two or more of the bony plates in a baby's head fuse prematurely. This rigidity pushes other parts of the head out of shape as the brain grows. This condition, known as craniosynostosis, is typically treated during infancy. To give the brain enough space to grow and develop, the fused bones must be surgically separated.

Remember, most cases of unevenness in babies' head shapes will resolve on their own. If you're concerned about your baby's head shape, check with your baby's doctor.

Jan. 29, 2015