Do birth injuries cause autism?

According to research released yesterday by the Centers for Disease Control and Prevention (CDC), the likelihood of a child being diagnosed with an autism spectrum disorder increased substantially between 2006 and 2008 – more than 20 percent. Today, doctors diagnose at least one in 88 children with autism, Asperger syndrome or another related disorder.

Researchers do not know what caused this increase. Some say that just because more children are being diagnosed with autism does not necessarily mean more children actually have autism than before; it might simply mean that doctors are detecting the disorder better and parents are more aware of it. Other researchers point to potential real causes, such as toxins in the environment and women giving birth later in life.

Yet, what if your child suffered a birth injury? Could that have caused his or her autism? Should you worry about autism if your baby was injured at birth?

Currently, there is no clear consensus about what causes autism. In the past, researchers have said that autism is generally hereditary, but a recent twins study suggests that the environment is a larger culprit. According to a British study, one of the biological contributors to autism could be complications at birth. That study found that children with autism are 12 times more likely to have suffered a birth complication than their siblings.

A study by Harvard School of Public Health and Brown University found that the following birth events may contribute to autism:

  •     Injuries caused by umbilical cords
  •     Fetal distress
  •     Breech births
  •     Birth trauma
  •     Maternal bleeding
  •     Anemia in the newborn

Many of the factors that were present in the study pointed to hypoxia (low levels of oxygen in the brain) as a potential cause for autism.

According to a science officer at Autism Speaks, “It appears that increased risk [of autism] is associated with a combination of several factors that may reflect what is referred to as suboptimal birth. And even then the risk may only be present when combined with a genetic vulnerability.”

Thus, we still have a long way to go before we can learn what birth injuries contribute to autism and if birth injuries are in fact the primary cause of autism in some children.

Source: The New York Times, “Autism Diagnosis Rising, Study Finds,” Benedict Carey, Mar. 29, 2012.