There is no known cause of autism spectrum disorder (ASD), so there is no way of determining the specific cause of your child’s autism. In fact, the generally accepted view is that there is no one specific cause of ASD. Rather, there’s a combination of factors that can increase a child’s risk.
Genetics and environment are two factors considered to affect the likelihood of a child developing ASD. Genetics may play a strong role, with the risk of a child having a pervasive developmental disorder increasing by 2% – 20% if an older sibling has an autism impairment.
Possible environmental causes often involve the child’s developing conditions in the womb. For example, the U.S. National Institute of Environmental Health Sciences cites “advanced parental age at time of conception,” and “prenatal exposure to air pollution or certain pesticides,” as two possible risk factors. However, research suggests that environmental factors play a marginal role in whether or not a child will develop autism. Experts instead point to genetics and continue to research exactly which genes mutate and lead to autism.
No matter the potential cause, parents and caregivers must focus on the child’s future rather than their past. Available evidence shows that autism tends to develop at an early age, meaning that a child born without autism is unlikely to “acquire” it when they are older.
The best response to an autism diagnosis is to seek evidence-based autism treatment that can help the family adjust and the child thrive.
ASD Cannot Be Diagnosed Through Genetic or Medical Testing
One of the first things to realize about the possible “cause” of ASD is that all of the causal models are theoretical.
For instance, while health professionals know that the presence of a sibling, parent, or close family member with autism can increase a child’s relative risk, there is not a genetic test for ASD currently available. Further, one of the largest comprehensive studies of genetics in individuals with autism revealed a staggering 102 genes that could be associated with ASD.
Similarly, while research has observed brain structure differences in individuals with a sensory disorder – a common co-occurring condition in those with autism – a large-scale study of brain scans of pediatric ASD patients shows no unified pattern of abnormalities.
Studies like these reveal that the causes of ASD could be as complex and diverse as the people themselves. Parents should be aware of risk factors, but more importantly, they should focus on what needs to be done to meet the child’s needs now that an ASD diagnosis has been established.
What Environmental Factors Might Raise the Risk of Autism?
There are several environmental factors that researchers theorize could raise the risk of a child developing autism. It’s important to note that these factors have been found to play a marginal role in the risk of developing autism, but they are still present. These include:
- Conceiving the child at an advanced age
- Very low birth weight
- Exposure to pollutants during pregnancy
- Infections during pregnancy
- Premature birth
The pattern in these environmental factors is that they might all affect the fetus’s brain development while in the womb.
“Studies suggest that ASD could be a result of disruptions in normal brain growth very early in development,” writes the National Institute of Neurological Disorders and Stroke. “These disruptions may be the result of defects in genes that control brain development and regulate how brain cells communicate with each other.”
Again, the influence of environmental factors is still entirely theoretical. There have been no studies establishing claims related to one or more factors. This includes the alleged link between immunization and autism, which has been disproven by over 25 studies.
Why Are More Children Being Diagnosed With ASD Now?
One reason some parents and interest groups say they want to search for a cause of autism is that the rates of diagnosis in children have, by all measures, skyrocketed.
A research review published in the early 2000s notes that between 1991 and 1997, the reported prevalence of pediatric autism increased 556%, “to a prevalence higher than that of spina bifida, cancer, or Down syndrome.”
However, the same study notes that “this jump is probably attributable to heightened awareness and changing diagnostic criteria rather than to new environmental influences.”
Indeed, one can track the evolution of autism diagnosis alongside developments as recent as the publishing of the 5th edition of Diagnostic and Statistical Manual of Mental Disorders (DSM–5) in 2013.
Prior to the 5th edition’s publication, a child with autism could instead be diagnosed with childhood disintegrative disorder, Asperger’s syndrome, or an unspecified form of pervasive developmental disorder (PDD-NOS).
Now, all of these possible presentations are grouped together as an autism spectrum disorder (ASD). Psychologists emphasize “spectrum” in particular because two children with ASD will most likely have vastly different needs and experiences.
Anyone who is still focused on the rise of autism diagnoses should realize that what this means is that many people with autism were undiagnosed or diagnosed with a different condition.
Therefore, it is likely that millions of people with autism in the past century or so failed to receive the appropriate treatment and care. Rather than worrying about the source of autism, recognize that care options for those with autism have improved dramatically in parallel with the rise in diagnostic frequency.
Giving Your Child the Best Possible Care to Help Them Thrive
After your child has been diagnosed with autism, you can take steps to identify their needs and strive to meet them through proactive treatment. Children with autism may need adjustments to their environment and care. Also, both the child and their parents can learn coping strategies for a variety of situations, helping avoid negative outcomes.
With the right approach, anyone with autism can be given the conditions they need to become the best version of themselves.