All studies showed an association between acetaminophen use and listed neuro developmental outcomes. Long-term use, increased dose, and frequency were associated with a stronger association.
Acetaminophen / paracetamol has a large range of suspected neuro-toxic effects. The initial development of the drug was during an age of far less stringent testing. While smaller observational studies can be questioned about validity, there are a large and growing number of these studies; and, as always, while there is doubt on the studies, the results are strongly trending in one direction, at this point the responsible action would be to avoid consumption of acetaminophen/paracetamol.