Maternal painkiller use and autism in children

Does paracetamol cause autism?

- Hannah Devlin, Ian Sample

The short answer is: no. Genetics plays a major role in autism, but scientists are also investigating the potential role of environmental factors such as parental age, premature birth and prenatal exposure to drugs, environmental chemicals or infections.

"The idea that something that occurs during pregnancy may influence neurodevelopment isn't a particularly new or crazy or outlandish idea," said Renee Gardner, an associate professor of epidemiology at Sweden's Karolinska Institute. "We know there's a large heritable or familial influence, but environment interacts with genetic tendencies." Paracetamol has been widely used for pain relief since the 1950s and is recommended by the NHS as the first choice of painkiller if you're pregnant. In recent years, a number of studies have suggested that women who take paracetamol during pregnancy are very slightly more likely to have a child who is diagnosed with autism. But this does not prove that the link is causal, and agencies such as the UK's Medicines and Healthcare products Regulatory Agency (MHRA) have stated there is no evidence that taking paracetamol during pregnancy causes autism in children.

Why do some studies suggest a link between paracetamol and autism?

A big challenge in human studies is working out what genuinely contributes to autism and what is simply associated with the condition.