Yes, according to research by neonatologist Paul Winchester, M.D., Indiana University School of Medicine professor of clinical pediatrics. Dr. Winchester, who studied 1,667,391 Indiana students, presents his finding on May 7 at the Pediatric Academic Societies' annual meeting.
Dr. Winchester and colleagues linked the scores of the students in grades 3 through 10 who took the Indiana Statewide Testing for Educational Progress (ISTEP) examination with the month in which each student had been conceived. The researchers found that ISTEP scores for math and language were distinctly seasonal with the lowest scores received by children who had been conceived in June through August.
Why might children conceived in June through August have the lowest ISTEP scores? "The fetal brain begins developing soon after conception. The pesticides we use to control pests in fields and our homes and the nitrates we use to fertilize crops and even our lawns are at their highest level in the summer," said Dr. Winchester, who also directs Newborn Intensive Care Services at St. Francis Hospital in Indianapolis.
"Exposure to pesticides and nitrates can alter the hormonal milieu of the pregnant mother and the developing fetal brain," said Dr. Winchester. "While our findings do not represent absolute proof that pesticides and nitrates contribute to lower ISTEP scores, they strongly support such a hypothesis."