(CBS) About 47 percent of infants have flat spots on their heads, according to a Pediatrics study released Monday.
The flat spots, called positional plagiocephaly, may be a result of the 1992 AAP recommendation to put infants to sleep on their backs to prevent Sudden Infant Death Syndrome (SIDS). While rates of SIDS have declined by 50 percent since those recommendations were released, it seems the flat spots have increased.
Positional plagiocephaly is usually caused because the child likes to lie in one position and their skull bones are soft, according to Seattle Children's Hospital. Premature babies are more at risk because their skull bones are even more pliable than full-term infants, and they are less likely to move their heads. Usually the side or back of the head is the only area affected, however, uneven foreheads have also been observed in some infants.
Out of the 440 infants between seven to 12 weeks of age examined by researchers, 46.6 percent had a flat spot on their head. Overall, 78.3 percent had a mild form of positional plagiocephaly. About 63.2 percent had it on the right side of their heads.
"That was pretty surprising. I didn't anticipate that it would be that high," study author Aliyah Mawji, assistant professor at the School of Nursing at Mount Royal University in Calgary, told the CBC.
Some children who have flattened skulls may have mild developmental delays that require additional treatment, Seattle Children's Hospital pointed out. Other children may experience torticollis, or muscle tightness that makes it difficult to move their neck, so they will need a physical therapist.
The researchers added that if not treated early, the deformities can be permanent and increase risk for teasing and bullying during school years.
To prevent the condition, American Academy of Neurological Surgeons recommends placing babies to sleep on their backs, changing the direction they face and changing the location of the baby's crib, so they can look in different directions outside the window. Give the child "cuddle time" when they are awake, and make sure kids have lots of supervised playtime on their stomachs so they aren't always on their backs. Avoid keeping them in car seats, carriers and bouncers for expended period of time, the researchers suggested.
"If the baby is constantly placed in the same position, so either the same feeding position or the same sleeping position or being left in car seats or bouncy swings, we see more of what we call the positional plagiocephaly," Mawji explained.
In special cases, children may have to wear a special helmet or band for most of the day if the condition is still moderate to severe after five months of age, the AANS said. Therapy can last from two to six months.
Dr. Roya Samuels, a pediatrician at Cohen Children's Medical Center in New Hyde Park, New York, downplayed the risk to HealthDay.
"Positional plagiocephaly is really a cosmetic issue," she said. "There's no evidence that it affects the brain."
She said the most important thing for new parents is to make routine well-child visits to their pediatrician, so the doctor can track the child's development, including his or her head shape and size.
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