What Causes Cerebral Palsy

Cerebral palsy results from genetic mutation or brain injury prior to, during, or shortly after birth. Ensuing symptoms vary greatly based on the severity of the injury and where it occurs. The following are a few of the most common causes:

Complications During Delivery

Breech birth (in which the child emerges with the knees or feet first) may cause severe trauma, including brain injury. This physical insult, in turn, can lead to cerebral palsy. CP may also occur if the baby is deprived of oxygen during delivery, as is common when the umbilical cord is wrapped around the neck (a condition often referred to as nuchal cord). Other causes of oxygen deprivation include placenta detachment and uterine rupture. Recent research indicates that birth complications are not responsible for CP nearly as often as once believed.

Untreated Jaundice and Kernicterus

In most cases, neonatal jaundice is a benign condition with few problematic health implications. However, if jaundice goes untreated for a significant period of time, it can lead to kernicterus, a type of brain damage attributed to high levels of bilirubin (a yellow compound typically found in bile) in the bloodstream. Although bilirubin is commonly present in adults, babies and infants struggle to rid it from their system. Excessive buildup of this compound can lead to brain damage, which ultimately manifests itself in CP symptoms. Kernicterus-related CP may also occur if there is a blood type difference between mother and baby.

Pregnancy-Based Infections

Cerebral palsy has traditionally been tied to complications during or immediately following childbirth, but in many cases, the brain injuries leading to CP actually occur in the womb. These injuries may be caused by infections that damage the developing fetus’ nervous system, including:

• Cytomegalovirus
• Rubella
• Toxoplasmosis
• Herpes
• Zika

During infection, the body produces cytokines, which regulate inflammation. Excessive cytokine levels increase susceptibility to oxygen deprivation. Cytokine production may occur in response to inflammation of the chorion (the fetus-surrounded membrane responsible for placenta production). The Collaborative Perinatal Project highlighted a link between chorionitis and cerebral palsy.

Genetic Mutation

Cerebral palsy typically occurs in response to inflammation or oxygen deprivation during childbirth, but genetic mutation may play a greater role in the disorder than previously assumed. The Australian Collaborative Cerebral Palsy Research Group cites genetic abnormality as responsible for 14 percent of cerebral palsy cases. This finding is consistent with the role of genetic mutation in other mental and developmental disabilities, such as epilepsy, autism, and schizophrenia. Further research is needed to determine how genetic mutations cause CP and how this risk can be mitigated.