To prevent sudden infant death syndrome (SIDS), the American Academy of Pediatrics recommends that babies sleep on their backs. Although our pediatric experts agree, it has given rise to a problem: When a baby sleeps only on his or her back, skull growth and development can be unfavorably affected.

How a Baby's Skull Forms

The skull consists of a number of bone plates that are naturally knitted together at sutures, or seams, where the bone plates overlap. One long suture goes from back to front in the middle of the skull. Other sutures extend to the forehead, sides and back of the skull. The body produces new bone at the suture lines. This allows the bones to grow evenly, resulting in an evenly shaped head.

The top and back of a newborn’s skull are very flexible. Many cultures, including ancient Egyptians and some Native American tribes, took advantage of this flexibility to mold babies’ heads into different shapes. They did this by wrapping bands around babies’ heads or placing babies on flat headboards.

Now, some modern parents are inadvertently doing the same thing. When a baby sleeps only on their back with the soft, thin bones at the back of the head supporting the weight of the skull and brain, a similar molding of the skull can occur. This condition is known as positional molding.

Because the baby’s head is very soft in both the bone and brain layers, it tends to deform like a beanbag — flattening in the back and front and widening on the sides. If your baby prefers one side of the back of his or her head to the other, the skull can take on an asymmetrical, lopsided shape. If most of the flattening is in the back of his head, it may be covered by hair and barely noticeable. But if the shape of the front and sides of his or her head also are affected, parents are likely to notice and to worry.

Plastic and reconstructive surgeon Russell Reid, MD, PhD., with Trish Lawson and her daughter Molly Lawson, 15 months old, at the Duchossois Center for Advanced Medicine (DCAM)

Craniofacial Anomalies Multidisciplinary Program (CAMP)

Our Craniofacial Anomalies Multidisciplinary Program (CAMP), one of the largest in the region, provides a thorough, team-based approach for the evaluation, diagnosis and treatment of children with craniosynostosis.

Learn more about our CAMP program