‘Babies who Stroke’: the leading known cause of cerebral palsy

Much is unknown about causation of cerebral palsy but that is not the case for children born at or near full term with hemiplegic (one sided) cerebral palsy. In 30% of these children a blood vessel supplying the brain has become blocked, usually by clot formation. The hemiplegia more commonly involves the right arm and leg as the site of thrombosis is the area of brain supplied by the left middle cerebral artery. Children may later have language difficulties and suffer from seizures. The risk of death from a neonatal stroke is 20-40%.Overall 50-80% of survivors have disabilities.
Mostly ‘cerebral infarction’ occurs before labour-for example as a result of clots forming in the feeder arteries. This may be part of a genetic thrombotic tendency such as Factor V Leiden –weakly present in 4-7 % of the population and strongly present in up to 0.25% of any population. Another cause may be a primary antiphospholipid syndrome (this occurs in up to 2% of the population).Boys are more frequently affected as are black races. The overall incidence of perinatal stroke is between 1:2300 and 1:5000 births.
The risk factors for the production of ‘ischaemic perinatal stroke’ include maternal factors such as thrombotic tendencies, autoimmune diseases, preeclampsia, prolonged rupture of membranes and chorio-amnionitis. The fetal factors include inherited thrombophilia, twin to twin transfusion syndrome, congenital heart disease, intra-uterine fetal growth restriction as well as fetal and neonatal infections such as meningitis.