Nearly half of all infants develop a flat spot on their heads by the two-month check up -- largely from being put to bed face up, per doctors' orders -- according to a Canadian study published online Monday in the journal "Pediatrics."
That's the bad news. The good news is that the spots frequently correct themselves, and they may be worth the risk: Back sleeping has reduced the rate of Sudden Infant Death Syndrome by more than 50 percent since 1994, according to the National Institute of Child and Human Development.
Canadian researchers studied 440 infants ages 7 to 12 weeks, finding that 205 of them -- 46.6 percent -- had some degree of flat spot from sleeping on their backs, known as "positional plagiocephaly." Most of the spots were mild (78.3 percent) and on the right side (63.2 percent), an apparent sleeping preference for babies.
The Mayo Clinic, which was not involved in the study, says the spots usually go away on their own as babies age, though parents can help lessen them by giving infants lots of tummy time while awake, holding them upright and encouraging them to turn their heads in different directions when they're going to sleep.
Positional plagiocephalyhas been on the rise since the early 1990s, when the American Academy of Pediatrics found that more infants died from SIDS if put to bed on their bellies. The academy soon launched a campaign recommending that babies sleep supine.
Tricia Bishop is a new mom who covers family issues for the Baltimore Sun.
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