The normal head circumference of a 1 year old baby is usually around 46cm, and over and under circumference of the head can indicate some pathologies.
Head circumference is the length of the head measured symmetrically around the head via the upper edge of the arch of the eyebrow and the occipital node. At the age of 1 year, the head circumference is about 46cm. At birth, the head circumference is usually around 33-34 cm; at 2 years of age, it is around 48 cm.
Growth in head circumference is generally associated with brain and skull growth, and its continuous measurement is more significant than a single measurement. The size of head circumference is also related to the head circumference of both parents and other factors. Generally speaking, a small head circumference is often indicative of cerebral dysplasia; a rapid growth rate of head circumference may indicate hydrocephalus.
It is recommended that 1-year-old babies undergo regular physical examination at the Child Health Service, and if there is any abnormality in the head circumference, targeted intervention can be carried out in a timely manner according to the doctor’s advice.