A Congenital and Climate Crisis

A School of Public Health professor and her postdoctoral fellow are making national headlines for their research finding that climate change could increase the number of U.S. infants born with congenital heart defects.

Shao Lin, a professor of Environmental Health Sciences, is senior author on the study published in the Journal of the American Heart Association and her postdoctoral fellow, Wangjian Zhang, is lead author. The research team, comprised of interdisciplinary experts across the U.S. and China, caution that continually rising temperatures will exacerbate pregnant women’s exposure to extreme maternal heat and result in as many as 7,000 additional congenital heart defect cases from 2025-2035.

The greatest percentage of increase in congenital heart defects is expected in the Midwest, followed by the Northeast and the South. The authors caution that the projected increase will pose greater demand on the medical community caring for these patients not just during their infancy, but potentially throughout their lifetime.

Previous research uncovered a link between maternal heat exposure and the risk of heart defects. While the precise cause remains unclear, experts believe that heat causes fetal cell death or interferes with heat-sensitive proteins that play a critical role in fetal development, particularly during the first trimester.

The research team used climate change forecasts from NASA and the Goddard Institute for Space Studies. They improved the spatial and temporal resolutions of the forecasts, simulated changes in daily maximum temperatures by geographic region and calculated the anticipated maternal heat exposure per region for spring and summer.

The research has been reported by more than 30 media outlets, including:

“Our findings underscore the alarming impact of climate change on human health and highlight the need for improved preparedness to deal the anticipated rise in a complex condition that often requires lifelong care and follow-up,” said Lin, who holds a medical degree. “It is important for clinicians to counsel pregnant women and those planning to become pregnant on the importance of avoiding extreme heat, particularly during the 3-8 weeks post conception.”

The study was done in collaboration with Lin’s colleagues from the National Birth Defect Prevention Study, the Environmental Protection Agency and Sun Yat‐sen University.