Causes Of Cerebral Palsy

Despite years of debate, the cause of the majority of cases of CP is uncertain.

Some contributing causes of CP are asphyxia, hypoxia of the brain, birth trauma, premature birth, central nervous system infections and certain infections in the mother during and before birth. CP is also more common in multiple birth.

Studies at the University of Liverpool have led to the hypothesis that many cases of cerebral palsy, and other conditions that an infant has at birth, are caused by the death in very early pregnancy of an identical twin. This may occur when twins have a joint circulation through sharing the same placenta. Not all identical twins share the same blood supply (monochorionic twins), but if they do, the suggestion is that perturbations in blood flow between them can cause the death of one and damage to the development of the surviving fetus[19][20][21] . It is common knowledge amongst obstetricians and midwives that a small dead fetus (fetus papyraceus) may sometimes be found attached to a placenta following birth. In the past, this has not been considered important and knowledge of the so called ‘vanishing twin’ has been suppressed to avoid triggering feelings of loss, grief, or guilt in mothers. The pathological consequences depend on the severity and the stage of development of the fetus when the imbalances in blood flow between the fetuses occur. It has been proposed that such pathology could account, not just for cerebral palsy, but for developmental abnormalities of the eye, heart, and gut, and other specific brain abnormalities such as neuronal migration disorders e.g. lissencephaly and holoprosencephaly, which occur during very early fetal development.

Between 40% and 50% of all children who develop cerebral palsy were born prematurely. Premature infants are vulnerable, in part because their organs are not fully developed, increasing the risk of hypoxic injury to the brain that may manifest as CP. A problem in interpreting this is the difficulty in differentiating between CP caused by damage to the brain that results from inadequate oxygenation and CP that arises from prenatal brain damage that then precipitates premature delivery.

Recent research has demonstrated that intrapartum asphyxia is not the most important cause, probably accounting for no more than 10 percent of all cases; rather, infections in the mother, even infections that are not easily detected, may triple the risk of the child developing the disorder, mainly as the result of the toxicity to the fetal brain of cytokines that are produced as part of the inflammatory response.[22] Low birthweight is a risk factor for CP--and premature infants usually have low birth weights, less than 2.0 kg, but full-term infants can also have low birth weights. Multiple-birth infants are also more likely than single-birth infants to be born early or with a low birth weight.

After birth, other causes include toxins, severe jaundice, lead poisoning, physical brain injury, shaken baby syndrome, incidents involving hypoxia to the brain (such as near drowning), and encephalitis or meningitis. The three most common causes of asphyxia in the young child are: choking on foreign objects such as toys and pieces of food; poisoning; and near drowning.

Some structural brain anomalies such as lissencephaly may present with the clinical features of CP, although whether that could be considered CP is a matter of opinion (some people say CP must be due to brain damage, whereas these people never had a normal brain). Often this goes along with rare chromosome disorders and CP is not genetic or hereditary.