There’s nothing like a newborn’s head — heavy, downy soft, just the right size to tuck in the crook of your neck. But what if, as you stroke your baby’s noggin, you notice a flattening at the back or off to one side? Is this something to be concerned about?
What is it?
So-called flat head, or flat spots on a baby’s head, is a condition known as plagiocephaly, a flattening of the bones of the skull. Flatness usually occurs on the back of the head, but can also happen on the side. It often becomes noticeable in the second or third month of life, although in some babies, flat spots are there from birth.
What causes it?
In a word, pressure. The bones of the newborn skull are soft and still growing (to allow for brain development), which makes them susceptible to moulding, explains Montreal paediatrician Denis Leduc, a past president of the Canadian Paediatric Society.
A recent study in the journal Pediatrics confirms that environmental causes account for the vast majority of plagiocephaly cases; physical deformities or genetic anomalies resulting in a misshapen skull are rare. “The most common cause is the baby spending long periods of time in the same physical position, which puts pressure on the skull,” says Leduc.
Babies with torticollis, where the range of motion in the neck is limited by muscle tightness, are more susceptible to flattening because they tend to favour turning the head to one side. How common is this? “The condition affects about two percent of newborns and is caused by the head being tilted to one side in the uterus during pregnancy, or by an injury to the neck muscle before or during delivery,” says Leduc. “Parents may notice that the baby holds her head to one side and has limited neck movement. There may also be a lump in the muscle on the side of the neck.”
Babies who have flat spots on their heads from birth often had, as Leduc puts it, “a small house.” A very tight fit in utero, due to a large baby or small uterine cavity, can put pressure on a developing skull.
A recent study has linked plagiocephaly with a delay in certain motor skills. However, it is unclear if it’s the flat spot itself or the lack of tummy time and movement that results in motor-skills delay.
Doctors have seen an increase in the number of cases of plagiocephaly in the last 20 years, coincident with the advice to put babies to sleep on their backs, the most important preventive measure against sudden infant death syndrome (SIDS). Do not put your child to sleep on his tummy because you are concerned about him developing a flat head.
How can it be prevented?
Varying your baby’s physical position is the best way to prevent flattening.
Alternate sleep orientation Babies like to have something interesting to look at and will turn their heads toward the room rather than the wall. On alternate days, change your baby’s position from one end to the other and check to make sure she’s looking out into the room. A mobile will encourage your baby to turn her head in alternate directions. Remember, always put your baby on her back to sleep until she’s old enough to choose her own sleep position.
Provide tummy time Once the umbilical stump has fallen off, babies should be placed on their tummies, when awake and alert, several times a day. Place a blanket under the baby so he doesn’t bang his face. At first he won’t stay in the position for long; young babies have heavy heads and poor neck muscle control. As he gets a little older and develops strength, it’s likely he’ll really enjoy tummy time, especially when there are some interesting toys to look at. When he’s had enough, pick him up.
Minimize use of seats Babies shouldn’t spend long periods in car seats and other baby holders. “Prolonged positioning where babies are tilted back is to be avoided,” says Leduc. “Babies should only be in their car seats while you’re travelling. Once you get there, the baby should be out of the seat. The seats should not be used for sleep.” Front carriers and slings are a better way to carry your baby when you’re not in the car.
How is it treated?
Most flattening isn’t permanent. If a baby has developed a flat head, Leduc recommends that parents vary their baby’s head position throughout the day. “With these measures, plagiocephaly will resolve in time.”
Helmets have been used to treat very severe cases, but Leduc is cautious, saying the research on this method is not yet conclusive.
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