My newborn baby has a big soft area on top of the head

Dear Doctor: My newborn baby has a big soft area on top of the head. When he cries it comes out and it keeps beating.What is the problem?

Dear Hajara: Mothers are wary about unusual things about their newborns especially when they are first time mothers and have little experience about what is normal and what is not.

Newborns have soft parts on their heads called fontanelles which allow the skull to deform during birth to ease its passage through the birth canal. After birth, the brain grows faster than the skull and the soft areas allow for the unequal growth.

Though these areas look soft, the membrane covering the fontanelles is extremely tough and difficult to penetrate and as such should not be over protected by parents assuming that they are exposing the brain to injury.

A normal fontanelle pulsates with the heartbeat and this pulsating action is how the soft areas got their name fontanelle, meaning “little fountain”.

The most prominent fontanelle is the anterior one, locally known as kawompo in Luganda or Engoma in Runyakitara. If it is larger than usual, it may indicate premature birth, growth retardation in the womb, increased pressure in the head (hydrocephalus) or a genetic problem called Down’s syndrome among others.

A sunken fontanelle may indicate dehydration, whereas a very tense or bulging anterior fontanelle may indicate raised pressure inside the skull or infection of the coverings of the brain (neonatal meningitis).

Prolonged crying by the baby may also lead to a bulging bregma without any medical issues.
While other fontanelles close earlier, the anterior is not completely closed until about the middle of the second year.