Autism is a condition characterized by poor social interaction, poor communication, and repetitive behaviors. The severity and range of these deficits vary greatly, and in fact, the condition is considered a spectrum disorder. The causes of autism have been the subject of considerable study and it is probable that there are actually many different processes involved. It is likely that there is a genetic component that may increase a child's risk of becoming autistic, as well as environmental influences that act on the developing central nervous system and produces changes that result in autism. A recent study, published in the November issue of Pediatrics, explored the links between preterm birth and autism. They looked at the pregnancy and birth records of 1216 autistic children and compared them to 6080 normally developing children. They noted the pregnancy, delivery, and neonatal complications that the children had experienced and determined which were seen more often in children with autism.

...[B]eing born early (preterm) did not itself increase the risk of autism. Rather, it was complications having a negative impact on brain development...that were the culprits.

They found that being born early (preterm) did not itself increase the risk of autism. Rather, it was complications having a negative impact on brain development during pregnancy, delivery, and the newborn period of the preterm infant that were the culprits. Specifically, the researchers found that babies who were born weighing less and being smaller than most babies had a higher risk of autism. Similarly, babies that experienced seizures or bleeding into or swelling of their brain tissue, had three times the risk of autism as same age babies without these complications. Additionally, babies who had abnormally formed heart and circulation systems had more autism. All these conditions can negatively impact brain growth and development.

When they looked at pregnancy complications, researchers noted that preeclampsia, a condition that impacts adequate delivery of oxygen and nutrients to the developing fetus was associated with an increased risk of autism. They hypothesized that impaired growth of the developing fetus was related to this risk. Additionally, when preeclampsia is severe, the infant may be delivered prematurely because the risk of continuing the pregnancy is more dangerous to mother and fetus than the risk of preterm birth. But, unfortunately, preterm births have increased risks of complications, many of which are associated with autism.

In full term babies, low blood sugar for several days, severe breathing problems, and severe jaundice were related to an increase in autism. Again, these conditions all can impact brain growth and development by changing the blood flow to the brain, causing inflammation, or increasing the risk of bleeding within the brain.

The researchers concluded that certain complications that affect brain growth and development are a common denominator of increased risk of autism in preterm as well as full term babies. Simply being premature, without these complications, does not increase the risk. It is important to remember that not all preterm and term infants with the complications described develop autism. It is likely the interaction of the infant's genetic make up with the medical complications she experiences early in life, which determine the outcome.

Although not curable, autism, like many other developmental disorders, benefits from early recognition and intervention. Parents who have concerns about their child's development should talk with their doctors. Parents should pay particular attention to their child's ability to communicate both with words and gestures and their ability to join in play with other children. The child's preschool teacher or babysitters are an important source of information about a child's behavior and skills. Parents seeking more information may find the following websites helpful: