To determine if the fontanel is closed, touch the top of the skull with your finger. If the fontanel is not closed, you will feel a gap, the size of which varies depending on the age of the month. If the fontanelle is closed, there is no such gap. Most fontanelles normally close between one and one and a half years of age, and it is important to monitor head circumference while the fontanel is closing. It is important to monitor the head circumference while the fontanel is closing, because the closure of the fontanel and the size of the head circumference can reflect the development of the skull and brain. If fontanelle closure and head circumference are normal, and the baby’s intellectual and motor development is normal, the overall development is good. If the fontanelle is closed but the head circumference is significantly smaller than normal, microcephaly is considered a possibility. Most of the children in this group will have overall developmental backwardness, so it is important to bring the baby to the Child Health Unit for regular monitoring of physical development.