Core Terms & Classification
Congenital hydrocephalus
Congenital hydrocephalus is hydrocephalus that is present at birth or develops during fetal development.
In short: Congenital hydrocephalus
- It is present from birth, arising during pregnancy.
- Causes include aqueductal stenosis, spina bifida, and infections.
- It occurs in roughly 0.2 to 0.8 per 1,000 live births.
- It can sometimes be detected before birth on imaging.
What it is
Congenital hydrocephalus is hydrocephalus that exists at birth, having developed during pregnancy. It can result from problems with how the brain and CSF pathways form, or from events during fetal development.
Understanding Congenital hydrocephalus
Causes include narrowing of the cerebral aqueduct (aqueductal stenosis), spina bifida (often with a Chiari II malformation), Dandy-Walker malformation, genetic conditions (such as X-linked hydrocephalus), and congenital infections. It is sometimes detected before birth on prenatal ultrasound or fetal MRI, which allows families to plan for care. Studies estimate congenital hydrocephalus occurs in roughly 0.2 to 0.8 per 1,000 live births, and a substantial portion of cases occur alongside other malformations or syndromes. These figures describe groups and vary across populations.
Why it matters
Understanding congenital hydrocephalus helps families see that it arises during development and can have several causes, some of which are detectable before birth. Identifying the cause and any associated conditions guides the care plan and the outlook.
Common questions
When does congenital hydrocephalus develop?
Before birth, during fetal development.
Can it be detected before birth?
Sometimes, on prenatal ultrasound or fetal MRI.
What causes it?
Aqueductal stenosis, spina bifida, infections, and genetic conditions, among others.
Bottom line
Congenital hydrocephalus is present at birth, has several possible causes, and can sometimes be detected prenatally.
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