A baby with hydrocephalus has extra fluid in and around the brain. This fluid is called cerebrospinal fluid (CSF). Most CSF is found in fluid-filled areas (ventricles) inside the brain. Its purpose is to cushion and protect the brain and the spinal cord.

Too much CSF can increase the pressure in your baby’s head. This causes the bones in your baby’s skull to expand and separate. The baby's head may look larger than normal.


Hydrocephalus is rare. It may be caused by the following:

  • The fluid is blocked from flowing through your baby’s head.
  • Your baby has problems absorbing the fluid.
  • Your baby makes too much fluid. This happens in rare cases.

This condition can be congenital. This means that your baby is born with it. Hydrocephalus can also happen later in life. Causes of this condition include:

  • Congenital aqueductal stenosis (narrowing of the aqueduct)
  • Neural tube defects, such as spina bifida
  • Premature birth
  • Infections
  • Tumors
  • Bleeding inside your baby’s brain
  • Birth injuries
  • Blood vessels in your baby’s head that aren’t formed right
  • Injuries


Symptoms can occur a bit differently in each child. They can include:

  • A full or bulging soft spot on the top of your baby’s head (fontanel)
  • Increasing head size (circumference)
  • Seizures
  • Bulging eyes and not being able to look up when facing forward
  • Visible scalp veins
  • Irritability
  • High-pitched cry
  • Poor feeding
  • Projectile vomiting
  • Sleepiness or bring less alert than usual
  • Developmental delays

The symptoms of hydrocephalus may seem like symptoms of other conditions. Make sure your child sees his or her healthcare provider for a diagnosis.


A healthcare provider may first spot this condition in your baby during an ultrasound in pregnancy. In many cases, hydrocephalus doesn't develop until the third trimester of the pregnancy. Ultrasounds done earlier in pregnancy may not show this condition.  

Your child may be diagnosed with this condition after birth. Your child’s healthcare provider will examine your child and ask you about your child’s prenatal, birth, and family history. If your baby is older, your child’s provider may ask if he or she is meeting milestones. Children with this condition may be likely to have developmental delays. If your child has a delay, his or her healthcare provider may check for underlying problems.

Your baby’s head may be larger than normal. Your child’s healthcare provider will measure his or her head. If your baby’s head size isn’t in the normal range, he or she will have tests. These tests can confirm hydrocephalus.


This test uses sound waves to create an image of the inside of the body. During pregnancy, this test can show the size of the ventricles inside of your baby’s head.


This test uses large magnets, radio frequencies, and a computer. Together, these show detailed images of organs and structures inside your baby’s body.

CT scan

This test uses X-rays and computer technology to make detailed images of any part of your baby’s body. These include bones, muscles, fat, and organs. CT scans are more detailed than X-rays.


Treatment will depend on your child’s symptoms, age, and general health. It will also depend on how severe the condition is.

The goal of treatment is to reduce the pressure inside your baby's head. This can be done by draining the fluid. Your child may need medicine to remove the extra fluid. Some children need surgery.

In surgery, a doctor usually places a mechanical shunting device in your baby’s head. This helps to drain the fluid from your baby’s brain. The fluid is directed to another part of your baby’s body, where it can be absorbed.

The shunt usually runs behind your baby’s ear. The tubing goes under your baby’s skin to the belly (abdomen), heart, or lung. Your baby's healthcare provider will decide the drainage location. This will be based on your baby’s condition, age, and other factors. The belly is generally the first choice. A VP (ventriculoperitoneal) shunt is often used to direct fluid into the abdomen.

What are the complications from the shunts or surgery for hydrocephalus?

Sometimes surgery and shunts can cause problems. Possible complications include:

  • Infection
  • Bleeding
  • A shunt that doesn’t work. It may drain too much or not enough fluid.

After surgery, your child’s healthcare team will tell you how to care for your baby at home. They’ll also tell you symptoms that are an emergency. If your child has these symptoms, call his or her healthcare provider right away.


Your baby’s healthcare provider may suggest genetic counseling if you plan to have more children. Through counseling, you can learn about the risk for this condition in future pregnancies. You may also need testing during pregnancy to check for hydrocephalus.

Living with

Hydrocephalus can affect your baby’s brain and development. Your child’s outlook depends on how severe his or her condition is. It also depends on other brain and health problems your baby has.  

The key to treating this condition is getting it diagnosed and treated early, and avoiding infections. Your baby will need regular checkups to make sure his or her shunt is working right. Your child’s healthcare team will work closely with you as your baby grows.

Key Points

  • A baby with hydrocephalus has extra cerebrospinal fluid (CSF) around the brain. The baby's head may look larger than normal.
  • This is a rare condition.
  • A healthcare provider may diagnose this condition during an ultrasound in pregnancy.  
  • The goal of treatment is to reduce the pressure inside your baby's head. This is done by draining the fluid or decreasing its production.
  • The key to treating this condition is getting it diagnosed and treated early, and avoiding infections.

Next Steps

Tips to help you get the most from a visit to your child’s healthcare provider:

  • Know the reason for the visit and what you want to happen.
  • Before your visit, write down questions you want answered.
  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you for your child.
  • Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are.
  • Ask if your child’s condition can be treated in other ways.
  • Know why a test or procedure is recommended and what the results could mean.
  • Know what to expect if your child does not take the medicine or have the test or procedure.
  • If your child has a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your child’s provider after office hours. This is important if your child becomes ill and you have questions or need advice.