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.

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.

This month’s newsletter explores the pandemic’s effects on autism rates, trends in co-occurring mental health conditions, and the impact of intranasal oxytocin.

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