What is Craniosynostosis?

Craniosynostosis is a birth defect in which the bones in a baby's skull join together too early. This happens before the baby's brain is fully formed. As the baby's brain grows, the skull can become more misshapen. The spaces between a typical baby's skull bones are filled with flexible material and called sutures. These sutures allow the skull to grow as the baby's brain grows. Around two years of age, a child's skull bones begin to join together because the sutures become bone. When this occurs, the suture is said to "close." In a baby with craniosynostosis, one or more of the sutures closes too early. This can limit or slow the growth of the baby's brain.

Content provided by the Centers for Disease Control and Prevention (CDC). For information and references about craniosynostosis please visit: Facts about Craniosynostosis.

*White, Black, Asian/Pacific Islander categories are all non-Hispanic

Data Source: California Birth Defects Monitoring Program Registry, 2012-2016 (PDF),

California Central Valley Counties (Fresno, Kern, Kings, Madera, Merced, San Joaquin, Stanislaus, and Tulare).

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