Cerebral Palsy - What Increases Your Risk
Premature birth and low birth weight
About half of all children who have
cerebral palsy (CP) are born
prematurely.1 The risk of a
baby having CP increases as the birth weight decreases. A baby who is born
prematurely usually has a low birth weight, less than
5.5 lb (2.5 kg), but full-term
babies can also have low birth weights. Multiple-birth babies are more likely
than single-birth babies to be born early or with a low birth weight.
It is estimated that about 80 out of 100 children
with CP had a disruption in the normal development of parts of their brain
during fetal growth.2 Low-birth-weight, premature babies are more likely than full-term,
normal-weight babies to have had developmental problems during fetal growth
that can injure the brain. For example, a condition called
periventricular leukomalacia, or PVL, which reflects injury to the white matter
of the brain, is more likely in babies born prematurely than in those born at
For information about fetal growth, see the
Interactive Tool: From Embryo to Baby in 9 Months .
Risk factors before birth
Babies born to teen mothers or to mothers age 35 and
older have a higher risk for cerebral palsy.
Also, a fetus's risk
for developing a brain abnormality or injury that leads to CP increases when
the mother has certain problems during her pregnancy, which may include:
- Infections, such as
cytomegalovirus infection (CMV), chorioamnionitis, and
- Exposure to certain
medicines, such as thyroid hormones, estrogen, or methotrexate.
- Use of alcohol or
- Other problems, such as bleeding in the uterus
during the sixth to ninth month of pregnancy, large amounts of protein in the
urine (proteinuria), or high blood sugar levels.
Risk factors for cerebral palsy at birth
cases, some babies develop CP as a result of complications during the mother's
pregnancy or at birth. Risk factors include:
- Premature birth. Premature babies are at
increased risk for developing bleeding in the brain (intraventricular
hemorrhage, or IVH), which may result in CP.
- Difficult or prolonged
labor. Brain infection or physical trauma (such as from the use of forceps or
other instruments, which is rare) are all risks associated with a problem birth
that can increase a baby's risk of developing CP. A lack of oxygen, although it
occurs less commonly, also increases a baby's risk. CP can itself cause a
baby to have a difficult birth because of body movement and posture problems
related to the condition.
Placenta abruptio. The placenta usually separates from
the wall of the uterus several minutes after the birth of the baby. If it
separates before the baby is born, the baby loses the blood and oxygen supply
from the mother, which increases the risk of developing
- Infections in the mother's uterus or vagina, such as
strep infections, that transfer to the baby during
Risk factors after birth
Risk factors for
developing CP just after birth or within the first 2 or 3 years of life are
related to brain damage and include:
- A serious illness, such as severe
lead poisoning (very rare). Early signs of concern
include breathing problems, low levels of thyroid hormone (thyroxine),
seizures, and low blood sugar levels (hypoglycemia). Babies born prematurely or
with a low birth weight are susceptible to these illnesses.
head injury from an accident or fall. This includes injury to a baby from
shaking, throwing, or other force (shaken baby syndrome, also called intentional head injury or IHI).
of oxygen to brain tissues, such as the result of a brain tumor or a
- Having some kinds of blood-clotting or