A study published in the Environmental Health Perspectives (EHP) in 2016 showed a significant correlation between pesticide exposure, particularly organophosphates, and other chemical exposures during pregnancy leads to increase autism-spectrum disorders and intellectual disabilities in children.
Various chemicals such as 1,3-butadiene (found in petroleum products), styrene (found in plastics and exhaust fumes), perchlorate (found in airplane fuel and fertilizers), vinyl chloride (found in personal care products) and many others are all known to create biochemical imbalances adversely affecting the brain and nervous system, hormonal imbalances, cardiovascular function, immune health, etc.
Ideally, women should be screened prior to getting pregnant, but also knowing chemical levels during pregnancy may also help to identify certain exposures that can at least be decreased to lessen the potential for problems. Other individuals can also be checked to evaluate their exposure risks as well.
A great test for environmental chemical exposure is the GPL-TOX which assesses for over 170 environmental chemicals.