Cerebral palsy (CP) is a result of injury to or abnormal development of the brain. In many cases, the exact cause of this injury is not known. The damage or abnormality may occur during pregnancy, birth, or within the first 2 to 3 years of life.
* Possible causes of CP during pregnancy or birth can be related to genetic or chromosomal problems, infections or health problems in the mother or fetus during pregnancy, or complications related to labor and delivery. Any of these problems can affect how a fetus grows or deprive a fetus or newborn of needed blood, oxygen, or nutrients. Health problems in a newborn, such as untreated low blood sugar, can also cause brain damage that leads to CP.
Possible causes of cerebral palsy during pregnancy or birth
Factors during pregnancy and at birth, often interrelated, may increase or contribute toward the chances that a baby is born with or will develop cerebral palsy (CP). Recent estimates suggest about 70% to 80% of children with CP experienced a disruption in normal brain development during fetal growth. 1 The exact cause of these disruptions is not known.
Birth trauma, in which a baby can be deprived of oxygen or sustain a brain injury, is a more rare cause of CP than previously thought, occurring in less than 10% of children with the condition. The exact cause-and-effect relationship between cerebral palsy and a difficult birth is often unknown. Sometimes a baby has an existing brain injury sustained during fetal growth that makes birth more difficult because of irregular postures or other problems. Often, it is impossible to determine whether the brain injury or abnormality that results in CP occurred during fetal growth, a problematic birth, or a combination of factors.
There are several possible causes of CP during pregnancy or birth.
Genetic or chromosomal disorders
Babies born with certain genetic disorders, such as the blood-clotting disorder thrombophilia, have an increased risk of cerebral palsy. Babies born to teen mothers or to mothers older than age 35 have an increased risk for chromosomal irregularities that may result in CP.
Exposure of the mother to harmful substances during pregnancy
Examples of harmful substances include radiation or certain medications, such as thyroid hormone or estrogen. These and other substances may interfere with normal fetal development. A woman who drinks alcohol or uses illegal drugs during her pregnancy increases the chance that her baby will develop cerebral palsy.
Infections and health problems in the mother during pregnancy or birth
Infections such as German measles (rubella), cytomegalovirus infection (CMV), and toxoplasmosis in the mother, especially in the first 6 months of pregnancy, have been linked to the development of cerebral palsy. Chorioamnionitis, an infection that causes inflammation within the placenta, may also disrupt normal brain growth and cause CP. 1, 2
Certain infections (such as strep infections) of the uterus or the vagina may pass to the baby during delivery. If these infections reach the baby's brain, CP may develop.
Other health problems in the mother during pregnancy, such as bleeding in the mother's uterus, having large amounts of protein in the urine (proteinuria), or having high sugar levels in the mother's blood are all examples of other problems that may be linked to a fetus developing CP.
Having a prolonged or difficult birth
A baby who has a prolonged or difficult birth may be deprived of oxygen, nutrients, or blood for a long enough period to sustain brain injury. For example, delivery of the placenta (afterbirth) before the baby can result in a baby losing the blood or oxygen supply from the mother too soon, which can result in CP.
The American College of Obstetricians and Gynecologists (ACOG) and the American Academy of Pediatrics (AAP) have established general guidelines to help health professionals identify whether a trauma incurred during birth is serious enough to cause brain injury that may result in a form of CP. These criteria include: 3
* A blood sample, taken from the umbilical cord, that may indicate a baby was deprived of oxygen during birth.
* Moderate to severe swelling of the brain in babies born at 34 weeks or later.
* Other physical signs to indicate only spastic or dyskinetic types of CP are possible.
* Testing that has ruled out other conditions, such as trauma, blood clotting disorders, infections, or genetic disorders.
* Possible causes of CP related to an early birth (premature birth) are related to the brain's development. Babies born too early are at risk for bleeding in the brain (intraventricular hemorrhage, or IVH). A condition called periventricular leukomalacia, or PVL, which reflects injury to the white matter of the brain, is also more likely in babies born prematurely than in those born at full term. Both IVH and PVL put a baby at risk for cerebral palsy.
Possible causes of cerebral palsy related to premature birth
A baby who is born early (premature) is more likely to have or be vulnerable to health problems than babies born at full term and with a normal birth weight. Poor health just after birth makes a baby more likely than a baby born healthy to develop cerebral palsy. However, the cause and effect of premature birth is often unclear. For example, infections or fetal growth developmental problems may be related; either can cause premature birth and CP.
Babies born prematurely or at a very low birth weight have an increased chance for complications that lead to brain injury or abnormal development. The most common complications include:
* Bleeding within the brain (intraventricular hemorrhage, or IVH). It is most common in babies born prematurely or with a very low birth weight. Although the exact cause isn't well understood, it appears to be related to a premature baby's fragile blood vessels within the brain. These blood vessels easily rupture, which causes bleeding that can lead to brain injury. IVH almost always occurs within three days after a baby is born.
* Injury to the white matter of the brain, resulting in death and softening of some parts of the brain (periventricular leukomalacia or PVL). Depending on its severity, PVL can result in varying degrees of abnormal development as a child grows and matures. PVL is thought to occur because of too little blood flow within areas of the brain either during fetal development, at birth, or during the first few days of life.
* Weighing less than 5.5 lb (2.5 kg) at birth may indicate existing health problems or make a newborn more susceptible to infections or problems that can affect brain development. Full-term babies sometimes have very low birth weights, although this occurs less often than in babies born prematurely.
Multiple-birth babies are more likely than single-birth babies to be born early or with a low birth weight. This also puts them at risk for poor health as newborns. These combined factors increase the risk of cerebral palsy.
Early signs of these types of complications include:
* Breathing problems.
* Low levels of thyroid hormone (thyroxine)
* Seizures
* Low blood sugar levels.
* Possible causes of CP within the first 2 or 3 years of life are usually related to brain damage from a serious illness, such as meningitis; a brain injury, such as from an accident or fall; or not enough oxygen getting to the brain tissue, such as from a near-drowning incident.
Cerebral palsy within the first 2 or 3 years of life
Some children develop cerebral palsy (CP) because they experience brain damage within the first 2 or 3 years of life. Risk factors for brain damage include:
* Serious illness. Severe jaundice (hyperbilirubinemia), meningitis, or severe lead poisoning (very rare) all can interfere with brain development and lead to CP.
* Serious brain injury. An accident or fall can injure the brain. This type of injury also can result from shaking, throwing, or slamming down a baby (shaken baby syndrome, also called intentional head injury or IHI).
* Lack of oxygen to brain tissues. Insufficient oxygen delivery to the brain can cause CP, such as the result of a brain tumor or a near-drowning incident.
* Low blood sugar. Some newborns with severe low blood sugar (hypoglycemia) may develop CP.
Jerald Chan writes for
http://www.cerebralpalsycure.info where you can find out more about
cerebralpalsy cure and other topics.
Jerald Chan writes for
http://www.cerebralpalsycure.info where you can find out more about
cerebralpalsy cure and other topics.
