Pregnant woman exposed to high levels of air pollution had children with lower IQs, researchers found. The study led by University of Washington and University of California, San Francisco accessed the IQs of a little over 1,000 pregnant women’s offspring between the ages of four and six. There was a 2. 5 point IQ difference between children whose mothers lived in the top 10% of the most polluted areas compared to those in the bottom 10%.