Causes

The brain abnormalities in Cerebral Palsy (CP) are associated with a variety of prenatal (before birth), perinatal (during birth), or postnatal (after birth) events. CP is mostly due to factors occurring before birth, however prenatal diagnosis is not available and often a cause cannot be found.

Prenatal risk factors (44%):

Genetic conditions (chromosomal disorders, hereditary spastic paraplegia), foetal malformations, intrauterine infections, prenatal strokes, maternal conditions e.g. diabetes, thyroid abnormalities, mercury exposure and maternal iodine deficiency.

Perinatal risk factors (27%):

Birth asphyxia (deprived of oxygen), prematurity, maternal pre-eclampsia (severe pregnancy induced hypertension), complications of labour and delivery, perinatal infections e.g. Group B Streptococcus infection, kernicterus (severe neonatal jaundice, sometimes due to blood group incompatibility).

Postnatal risk factors (5%):

Infections in early infancy (meningitis, encephalitis), bleeding in the brain, head injury e.g. as a result of child abuse.

In 24% of people with cerebral palsy, the cause is not obvious. This percentage may drop with the advances in diagnostic facilities.