Authors' Response: More research on paracetamol is required

In his letter to the editor, John Cannell of the Vitamin D Council proposes ideas on how paracetamol might be linked to autism spectrum disorder (ASD) in women with vitamin D deficiency. These are interesting thoughts that deserve attention. In the letter, Cannell proposes that the adverse neurodevelopmental symptoms observed in our study 1 are consistent with ASD. However we would like to argue that the symptoms described in our paper could be equally relevant to other neurodevelopmental disorders such as attention deficit hyperactivity disorder or language disorders. It is correct that communication problems are a central feature of ASD, but not all children with communication problems have ASD. In fact most children with communication, behavioural or motor problems do not have ASD. Moreover a central feature of ASD is social problems. We did not find any association between paracetamol and sociability in our study. Studies involving clinical diagnoses are necessary to confirm or refute a possible connection between prenatal paracetamol exposure and ASD or other neurodevelopmental disorders. Such a future