Ever wondered why some newborn babies heads are oblong, resembling ‘cone heads’ after birth and then go back to normal? It is obvious that babies heads are under an enormous amount of pressure during birth, and this is especially so in humans. But how does the actual moulding of the head occur? A newborn baby’s skull bones can move during birth because of the soft tissue between them making the skeletal anatomy somewhat flexible and malleable (figure 1). There are some larger areas of soft tissue between the bones in the front and back portions of the skull called fontanelles.
Figure 1: Childbirth head moulding. From http://keckmedicine.adam.com/content.aspx?productId=117&pid=1&gid=002270
During birth these spaces between the bones allow the baby’s head to change shape. Depending on the amount and length of pressure, the skull bones may even overlap. This overlapping can produce a variety of shapes of the skull from a pointed to a flattened shape (figure 2). This normal moulding generally goes away in a matter of days.
Figure 2: Normal variations of head moulding. From: http://www.open.edu/openlearnworks/mod/oucontent/view.php?id=272&printable=1
These spaces between the bones also allow for the growth of the brain throughout infancy and childhood.