Kids whose moms had medium levels of a chemical called PFHxS during pregnancy seem to act more withdrawn or emotionally reactive by preschool age—but not if the exposure was very high, which is kind of surprising.

What we've found so far does not support a link between medium prenatal exposure to PFHxS and more emotional or withdrawn behavior in young children. Our current analysis shows the evidence leans against this idea. We reviewed one assertion suggesting that preschool-aged children whose mothers had medium levels of PFHxS during pregnancy might show more withdrawn or emotionally reactive behaviors [1]. However, in the same assessment, 62.0 other pieces of evidence contradicted this claim [1]. That means the weight of the evidence we’ve analyzed so far points away from this connection. Interestingly, the assertion noted that high exposure was not linked to these behaviors either, which adds complexity to how we understand these chemicals and child development. Our analysis is based on limited input—only one assertion made this specific claim, and it stands in contrast to a much larger number of findings that do not support it. We don’t know why medium exposure would lead to these behaviors, and the evidence we’ve reviewed does not back that idea. At this point, we can’t say that medium prenatal PFHxS exposure is meaningfully linked to emotional or withdrawn behavior in young children. As we continue to analyze new data, our understanding may change. For now, based on what we’ve reviewed, there’s no strong signal that medium PFHxS exposure during pregnancy affects children’s emotional or social behavior in early childhood. Practical takeaway: If you're concerned about chemical exposure during pregnancy, know that current evidence doesn’t suggest medium levels of PFHxS are linked to emotional or withdrawn behavior in young kids.