Learn About Increased Head Circumference
Increased head circumference is when the measured distance around the widest part of the skull is larger than expected for the child's age and background.
Macrocephaly
A newborn's head is usually about 2 cm (0.78 inch) larger than the chest size. Between 6 months and 2 years, both measurements are about equal. After 2 years, the chest size becomes larger than the head.
Measurements over time that show an increased rate of head growth often provide more valuable information than a single measurement that is larger than expected.
Increased pressure inside the head (increased intracranial pressure) often occurs with increased head circumference. Symptoms of this condition include:
- Eyes moving downward
- Irritability
- Vomiting
Increased head size may be from any of the following:
- Benign familial macrocephaly (family tendency toward large head size)
- Canavan disease (condition that affects how the body breaks down and uses a protein called aspartic acid)
- Hydrocephalus (buildup of fluid inside the skull that leads to brain swelling)
- Bleeding inside the skull
- Disease in which the body is unable to break down long chains of sugar molecules (Hurler or Morquio syndrome)
Your health care provider usually finds an increased head size in a baby during a routine well-baby exam.
A careful physical exam will be done. Other milestones for growth and development will be checked.
In some cases, a single measurement is enough to confirm that there is a size increase that needs to be tested further. More often, repeated measurements of the head circumference over time are needed to confirm that the head circumference is increased and the problem is getting worse.
Diagnostic tests that may be ordered include:
- Head CT scan
- MRI of the head
- Cranial ultrasound
Treatment depends on the cause of the increased head size. For example, for hydrocephalus, surgery may be needed to relieve the buildup of fluid inside the skull.
Duke Children's Health Center Neurology Clinic
Mohamad Mikati is a Pediatrics provider in Durham, North Carolina. Dr. Mikati is rated as an Advanced provider by MediFind in the treatment of Increased Head Circumference. His top areas of expertise are Alternating Hemiplegia of Childhood, Epilepsy in Children, Wolf-Hirschhorn Syndrome, and Increased Head Circumference. Dr. Mikati is currently accepting new patients.
Ghayda Mirzaa is a Medical Genetics specialist and a Pediatrics provider in Seattle, Washington. Dr. Mirzaa is rated as an Elite provider by MediFind in the treatment of Increased Head Circumference. Her top areas of expertise are Increased Head Circumference, Cortical Dysplasia, Achalasia Microcephaly Syndrome, and Microcephaly. Dr. Mirzaa is currently accepting new patients.
William Dobyns is a Medical Genetics specialist and a Pediatrics provider in Chicago, Illinois. Dr. Dobyns is rated as an Elite provider by MediFind in the treatment of Increased Head Circumference. His top areas of expertise are Increased Head Circumference, Cortical Dysplasia, Cerebellar Hypoplasia, and Lissencephaly. Dr. Dobyns is currently accepting new patients.
Summary: PtenTurkiye.org' is a national ( Turkish), web-based registry for PTEN Hamartoma Tumour ( PHTS) syndrome established in 2022. It is designed to increase awareness, gather scientific knowledge by collaboration and increase data accessibility, collect high-quality data on the epidemiology, genetic background and natural history of PHTS especially for pediatric patients so that more accurate follow u...
Summary: The purpose of this study is to determine cross-sectional and longitudinal medical, behavioral, and cognitive differences between PTEN ASD and other groups, as well as to identify cognitive, neural systems, and molecular biomarkers specific to PTEN ASD. In addition, this study will be creating and maintaining a biorepository and linked phenotypic database for PTEN ASD.
Published Date: April 05, 2025
Published By: Charles I. Schwartz, MD, FAAP, Clinical Assistant Professor of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, General Pediatrician at PennCare for Kids, Phoenixville, PA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
Bamba V, Kelly A. Assessment of growth. In: Kliegman RM, St. Geme JW, Blum NJ, et al, eds. Nelson Textbook of Pediatrics. 22nd ed. Philadelphia, PA: Elsevier; 2025:chap 27.
Mitchell AL. Congenital anomalies. In: Martin RJ, Fanaroff AA, eds. Fanaroff and Martin's Neonatal-Perinatal Medicine. 12th ed. Philadelphia, PA: Elsevier; 2025:chap 29.