A new study just published in the August online edition of Pediatrics confirms what I see in my practice. According to this study the incidence of positional plagiocephaly (head flattening) has increased and is now estimated to occur in about 47% of babies between the ages of 7 and 12 weeks.
The recommendation to have babies change from the tummy sleeping position to back sleeping was made in 1992. Since that time there has been a greater than a 50% decline in the incidence of SIDS. (see old posts). But both doctors and parents have noticed that infants have sometimes developed flattened or misshapen heads from spending so much time being on their backs during those first few months of life.
This study was conducted in Canada among 440 healthy infants. In 1999, Canada, like the U.S., began recommending back sleeping for babies. Canadian doctors had also reported that they were seeing more plagiocephaly among infants.
The authors found that 205 infants in the study had some form of plagiocephaly, with 78% being classsified as mild, 19% moderate and 3% severe. Interestingly, there was a greater incidence (63%) of a baby having flattening on the right side of their heads.
Flattening of the head, either on the back or sides is most often due to the fact that a baby is not getting enough tummy time. Although ALL babies should sleep on their back, there are many opportunities throughout a day for a baby to be prone on a blanket while awake, or to spend time being snuggled upright over a parent's shoulder or in their arms. Limiting time spent in a car seat or a bouncy chair will also help prevent flattening.
Most importantly, I tell parents before discharging their baby from the hospital that tummy time needs to begin right away. It does seem that some babies have in utero positional preference for head turning and this needs to be addressed early on. Think of a baby being just like us, don't you like to sleep on one side or another? By rotating the direction the baby lies in the crib you can help promote head turning and prevent flattening.
Lastly, most cases of plagiocephaly are reversible. Just put tummy time on your daily new parent to do list.