• The mother may be exposed to an infection, such as German measles (rubella).
• The mother may have unknowingly been exposed to an environmental toxin, such as  mercury, or she may have taken drugs or medicines that she did not know would harm the infant.
• The mother may have consumed unsafe levels of alcohol.
• Tobacco use during pregnancy can lead to low birth weight.
• The mother may have had inadequate nutrition.
• Rh incompatibility between the mother and the infant used to be a common factor, but now there is a treatment that can be given to the mother that has reduced that risk.
• Other complications that can arise in the mother's health during pregnancy and that can play a role include vaginal bleeding after the sixth month, hyperthyroidism, high blood pressure, and proteinuria.

Complications At or Around Birth
Although lack of oxygen during birth can be a factor in cerebral palsy, it has been discovered that, for most babies, the damage is likely to have taken place before birth.  In these cases, the delivery may be slower because the baby cannot move normally to assist in the process.

There are several risk factors that might lead to cerebral palsy:

• Insufficient oxygen during birth, which may be caused by an umbilical cord wrapped around the neck or severe contractions that decrease the blood flow (and oxygen) to the brain.
• A difficult or prolonged delivery, such as breech birth (born feet or buttocks first).
• The baby may have a low Apgar score.  The Apgar test is routinely given to newborns.  It consists of scoring the infant on the following criteria: heart rate, breathing, muscle tone, reflexes, and skin color.  Each are scored as 0 (low), 1 (intermediate), or 2 (normal) after delivery.  A total score of 7-10 at five minutes is considered normal, 4-6 intermediate, and 0-3 low. Scores that remain low 10 to 20 minutes after delivery indicate increased risk for cerebral palsy.