From the Research
The fontanelle in a child's head is typically fully closed by 12 to 18 months of age, with a median closure time of 9.7 months, as reported in the most recent and highest quality study 1. The anterior fontanelle, which is the largest and most important for clinical evaluation, usually closes between 12 to 18 months. The fontanelles are important because they allow for brain growth and slight skull movement during birth. As the brain grows and the skull bones fuse, the fontanelles gradually close. This process is a normal part of infant development and doesn't require any specific intervention. Some key points to consider:
- The size of the anterior fontanelle can vary significantly among healthy children, with a mean size of 2.1 cm at birth and a median closure time of 13.8 months, as reported in an earlier study 2.
- Early or delayed closure of the fontanelle can be a sign of an underlying medical issue, such as increased intracranial pressure or certain genetic disorders, as noted in several studies 2, 3, 4, 5.
- Parents should monitor their child's fontanelle closure during regular check-ups with their pediatrician and consult their pediatrician promptly if they notice any unusual bulging, sinking, or delayed closure of the fontanelles. The most recent and highest quality study on this topic, published in 2018, provides the most accurate and reliable information on fontanelle closure time, making it the best guide for clinical practice 1.