Autism is a developmental disability that usually appears during the first three years of life. It is a neurological disorder that impacts the normal development of the brain in the areas of social interaction and communication skills. Researchers have yet to pinpoint any single cause of autism, but studies indicate that it is related to abnormal brain structure and/or function. There are several factors during pregnancy that have been associated with autism, including:

• Maternal diet: Studies have linked autism to the mothers diet during pregnancy. For example, folate, or vitamin B9, is required for the process that turns on and off genes that govern brain wiring in the days immediately following conception.

• Maternal medicines: Some medicines taken by the mother during pregnancy have been linked to autism. For example, antidepressants have been associated with an increased risk of autism.

• Maternal immune and metabolic conditions: Preeclampsia, a form of high blood pressure, and gestational diabetes have been linked to autism. Children with autism are twice as likely as typical children to have been exposed to preeclampsia.

• Maternal exposure to hormones: Maternal exposure to hormones during pregnancy is linked to a higher risk of the development of autism in offspring.

• Pregnancy complications: Advanced maternal and paternal age at birth, maternal gestational bleeding, and exposure to pregnancy complications in general may increase the risk of autism.

It is important to note that there is insufficient evidence to implicate any one prenatal factor in autism etiology. While many studies support the hypothesis that obstetrical complications may increase the risk of autism, the specific complications, magnitude of effect, and overall conclusions of these studies are inconsistent.