This week the Statens Serum Institut in Copenhagen released a study of more than 340,000 boys. In it, researchers claimed those who were circumcised are up to 46 percent more likely to develop autism spectrum disorder (ASD) later in life. The research, lead by Professor Morten Frisch, concluded that a "single painful injury" could lead to "lifelong deficits in stress response." This means that a physical trauma early in life could create an emotional response that ends in ASD before the child is 10-year-old.
Although circumcision in the West is performed with pain relief, the procedure is never totally pain free. The study graphically adds that the procedure is universally more painful for infants as "Older children whose foreskins have already spontaneously separated from the glans will only experience the pain associated with the foreskin incision." Carry that sentence with you into your day. In line with this information they noted that for children under the age of five, the likelihood of developing autism rises to 50 percent.
Like many autism studies before it, the findings were immediately controversial and saw a noticeable backlash in Jewish communities. But it also brought up questions over the difference between factual causation and general correlation when reviewing results.
The study hinges on the impact pain can have on a developing brain, but Professor Trevor Parry from the University of Western Australia's School Paediatrics and Child Health is immediately sceptical of the link: "I'm not convinced that trauma being a factor is the case. There are many other things, like teething, that are arguably more common and painful in children's lives. Children fall, they scrape their knees, they experience more pain than the relatively momentarily discomfort of circumcision."
Despite Trevor's query over the commonality of physical pain in childhood, the link between early trauma and autism has been suggested before. However, the connection is difficult to confirm due to trauma's lasting effects often being similar to autism symptoms and therefore easy to mistake. Adolescent psychologist Gillian Hanna explains, "The way trauma presents looks similar to autism so it's quite difficult to pull apart the two things. There are ways of doing it obviously, but it's a very tricky process".
Rather than focus on the role that pain plays, Gillian suggests that the study's focus on boys is more likely to be the reason for the results being so high. "Boys tend to be more easily identifiable than girls just because of the way that autism seems to present in boys. Girls can make autism look like normal behaviour just because of the way they play," Gillian said.
Trevor is more direct, noting that autism — like most developmental problems — is more common in boys. And as language delay is a key diagnosing feature of the disorder, this figure can be further skewed towards males as, "generally speaking boys have more struggles with language development that girls do."
The reality is that any large study focusing of males under five, such as one looking at circumcision, would return higher rates of autism than similar research with an unsegregated sample group simply because girls social difficulties emerge later.
While many specialists tie the increase in autism numbers with a greater understanding of the disorder and an ability to recognise it, Trevor does believe we are missing an environmental aggregator. And despite not believing circumcision is it, he notes: "There's a remarkable increase in its prevalence which has been emerging in the last decade. It's something like nine in 160 children, which is bizarre, but scientifically a mystery."
Interstingly, a global reduction in the rate of male circumcision is in opposition with the Danish findings. "In which case you would have expected to see a decline in the number of autism diagnosis," concludes Trevor.
The continuing desire to find an external trigger for the disorder is understandable. If we know what's causing it, we'll have a huge advantage when trying to treat it. But although progress is being made, as it stands there is no known etiology of autism. The only tangible explanation is the genetic component — if a parent has autism there is a good chance their child will as well.
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