What Is Cerebral Palsy? What Causes It?

Medically Reviewed by Renee A. Alli, MD on May 31, 2021

Cerebral palsy, or CP, is a group of disorders that affect balance, movement, and muscle tone. “Cerebral” means the disorder is related to the brain, and “palsy” refers to weakness or a muscle problem.

CP starts in the area of the brain that controls the ability to move muscles. Cerebral palsy can happen when that part of the brain doesn’t develop as it should, or when it is damaged right around the time of birth or very early in life.

Most people with cerebral palsy are born with it. That’s called “congenital” CP. But it can also start after birth, in which case it’s called “acquired” CP.

People with cerebral palsy can have mild issues with muscle control, or it could be so severe that they can’t walk. Some people with CP have difficulty speaking. Others have intellectual disabilities, while many have normal intelligence.

What Causes It?

Doctors can’t always figure out exactly what has happened to damage the brain or disrupt development, causing CP.

Some of the problems that can damage the brain or disrupt its growth include:

  • Bleeding in the brain while the baby is in the womb, during birth or afterward
  • A lack of blood flow to important organs
  • Seizures at birth or in the first month of life
  • Some genetic conditions
  • Traumatic brain injuries

Am I at Risk for Having a Child With CP?

You may have a condition while you’re pregnant that can increase the chances your baby will have CP. Among them are:

  • Being pregnant with multiples, such as twins or triplets
  • Having a health issue such as seizures or a problem with your thyroid gland
  • Having blood that’s not compatible with your baby’s, which is also called Rh disease
  • Coming in contact with a toxic substance such as mercury, which is found in some kinds of fish

Certain infections and viruses, when they strike during pregnancy, can increase the risk your baby will be born with cerebral palsy. They include:

Can My Baby Have CP Even If I Don’t Have any High-Risk Conditions?

Just as some illnesses in mothers raise the chances of CP, so do some infections in babies. Here are some of them:

  • Bacterial meningitis. It causes swelling in the brain and tissues around the spinal cord.
  • Viral encephalitis. This also can cause swelling around the brain and spinal cord.
  • Severe jaundice (yellowing of the skin). This condition occurs when excessive bilirubin, a yellow pigment, accumulates in the blood.

Certain problems that happen in childbirth can also increase the risk of cerebral palsy. They include:

  • Premature birth.This means any time under 37 weeks into the pregnancy.
  • Breech position. This means a baby is settled feet-first rather than headfirst when labor begins.
  • Low birth weight. If your baby is less than 5.5 pounds, the chances for CP go up.
  • Complicated labor and delivery. This means problems with your baby’s breathing or circulatory system.
WebMD Medical Reference



CDC: Cerebral Palsy (CP).

Gillette Children’s Specialty Healthcare: Cerebral Palsy.

National Institute of Neurological Disorders and Stroke: Cerebral Palsy.

American Academy of Pediatrics: Cerebral Palsy.

March of Dimes: Cerebral Palsy.

Mayo Clinic Health Library: Cerebral Palsy.

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