Indiana University School of Medicine researchers are learning more about the effects of herbicide exposure during pregnancy, finding glyphosate in 99 percent of the pregnant women they observed in the Midwest. In the study, published recently in Environmental Health, higher glyphosate levels were associated with lower birth weight and may also lead to higher neonatal intensive care unit admission risk.

This is the second small-scale study the researchers have conducted with significant findings. The team’s previous study, published in 2018, was the first study to confirm glyphosate in 93 percent of pregnancies which found associations with shortened pregnancies. Other recent studies have also confirmed their findings.

“Pesticide exposure in pregnancy, especially in early pregnancy, can imprint DNA and alter gene expression,” said Paul Winchester, MD, professor of clinical pediatrics and the study’s lead author. “But little is known about how these chemicals can impact fetal development in humans.”