This month’s issue of the Null and Noteworthy newsletter breaks down some negative results involving prenatal exposures, an experimental treatment for Angelman syndrome, and the role that age at autism diagnosis plays in subsequent outcomes, and more.

As acetaminophen lawsuits make their way through the U.S. court system, researchers reevaluate the quality of the evidence linking in-utero exposure to the painkiller to neurodevelopmental issues in children.

A study published last week in JAMA Pediatrics suggests that autism is more common among people born in areas with high levels of lithium in drinking water, but it is too soon to say whether prenatal lithium exposure is truly a concern.

The changes may help explain the link between maternal infection and autism, though more research is needed.

Exposing neurons to valproic acid, a well-known environmental risk factor for autism, disrupts their ability to generate different proteins from the same gene.

Blocking the enzyme, called TOP2A, in embryos makes the animals less inclined to seek companionship later in life.

Having an infection during pregnancy is tied to a small increase in the chances of having an autistic child, but the connection may not be causal.

The long-standing link between maternal infection during pregnancy and having a child with autism may reflect common genetic or environmental factors instead.

Showing an association is not enough to determine causation.

When Van de Water isn’t busy mentoring “the next generation of scientists” in her lab, she finds time to paint, watch HGTV and hang out with her horse, Hank.