Cerebral palsy can be caused by a brain injury or an interference in brain development. Sometimes these disturbances occur because of genetic changes.

Conditions that are Associated with an Increased Risk for Cerebral Palsy

This is a list of conditions currently known to increase the risk of, or cause, cerebral palsy, however, with ongoing research, this can change.

Cerebral palsy causes are not always known. Lily is pictured with a big smile in a blue swing at the end of its pendulum motion

  • Maternal infection
  • Infant stroke
  • Multiple births
  • Premature birth
  • Other issues affecting how blood and oxygen move throughout the developing brain
  • Bleeding in the brain before, during, or after birth
  • Infections of the brain, including meningitis or encephalitis
  • Shock, a state in which organs and tissues do not receive adequate blood flow
  • Traumatic brain injuries, such as from a serious car accident
  • Seizures at birth or in the first month following birth
  • Certain genetic conditions

Diagnosing cerebral palsy involves the use of multiple examinations and tools. Some of these tools include an analysis of the infant’s movements (ie GMA, HINE and TIMP etc), imaging of the brain, and physical examinations of muscle tone

Although any one risk factor may cause cerebral palsy, more often it is caused by the presence of multiple risk factors.

Research Highlights Regarding Causes of Cerebral Palsy

Blake hugs Lilly -- Knowing the cause of cerebral palsy can help parents understand more about the life course with CP

  • The research literature suggests that events during pregnancy are more likely to cause cerebral palsy than events during labor or delivery. 
  • A major US study, called the Collaborative Perinatal Project, conducted between 1959 and 1974 followed approximately 50,000 women and their children from the first prenatal visit until the children were seven years old. It found that events during labor and delivery were not major contributors to the occurrence of cerebral palsy; most cases had their origins before labor began. A second finding was that intrauterine inflammation was a major cause of adverse pregnancy outcome[1].
  • At least 70 percent of cases of cerebral palsy have antecedents* during pregnancy, and only 10 to 20 percent of cases are related to the child’s birth[2].
  • Neither the routine use of fetal monitoring during labor nor the increased incidence of caesarean births (factors which reduce risk during labor and delivery) have reduced the number of cases of cerebral palsy[2].
  • Most brain injuries which cause cerebral palsy occur in the second half of pregnancy, a period when the rate of brain development is fastest[3].
  • Some risk factors are on the decline, but others are increasing[2][3]. Advances in neonatal care have reduced the risk of birth injury. However, with these advances more preterm infants, and infants with low birth weight, are surviving, some of whom may develop cerebral palsy.
  • The fact that some risk factors are decreasing while others are increasing is leading to a change in the type of cerebral palsy that develops. For example, an injury to the brain at 24 weeks can have a different effect than one at 28 weeks or 36 weeks. Until recently, babies born at 24 weeks would not have survived. Now, thankfully, many of these babies survive; however, some may develop cerebral palsy.
  • The most common types of cerebral palsy differ in different parts of the world, depending on risk factors.
  • In approximately 90 percent of cases, cerebral palsy results from healthy brain tissue becoming damaged rather than from abnormalities in brain development.[4]
  • Confirmation of the presence of a brain injury by magnetic resonance imaging (MRI) occurs in many, but not all cases. Up to 17 percent of people with cerebral palsy have normal MRI brain scans[4]. Imaging may also help determine when the brain injury occurred[4].
  • The cause of cerebral palsy in an individual child is often unknown[5].

Although the cause of cerebral palsy is not progressive (the injury, genetic cause, changes in brain development, etc., does not get worse), the presentation and symptoms may change over time as the brain develops further and there is ongoing wear and tear on the muscles and bones.

Doctors have a good understanding of the risk factors for cerebral palsy but there is still much we have to learn about why some babies develop cerebral palsy and others do not. There are many babies who share similar risk factors, injuries and diagnoses but develop very differently.

* Things that existed before or that logically preceded another event.

For more information, download our free cerebral palsy tool kit.

References and Sources
  1. Klebanoff, M. (2009, January). The collaborative Perinatal project: A 50-year retrospective. Retrieved June 01, 2021, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2646177/
  2. Flynn, J. M., & Weinstein, S. L. (2014). Lovell and WINTER’S pediatric orthopaedics.; Philadelphia, PA: Wolters Kluwer Health/Lippincott Williams & Wilkins. doi:https://solution.lww.com/book/show/322001#tab_about[abstract]
  3. Hadders-Algra, M. (2014, September 24). Early diagnosis and early intervention in cerebral palsy. Retrieved June 05, 2021, from https://pubmed.ncbi.nlm.nih.gov/25309506/
  4. Graham, H., Lieber, R., Crompton, K., Reddihough, D., Colver, A., Gaebler-Spira, D., . . . Rosenbaum, P. (2017, January 7). Cerebral palsy. Retrieved June 05, 2021, from https://pubmed.ncbi.nlm.nih.gov/27188686/
  5. Rosenbaum, P., & Rosenbloom, L. (2012). Cerebral palsy: From diagnosis to adult life. London: Mac Keith Press.
  6. Nelson, MD, K. B. (2008, December). Causative factors in cerebral palsy : Clinical obstetrics and gynecology. Retrieved June 01, 2021, from https://journals.lww.com/clinicalobgyn/Abstract/2008/12000/Causative_Factors_in_Cerebral_Palsy.14.aspx[abstract]