Climate Change May Hurt Babies' Hearts
Get the world’s most fascinating discoveries delivered straight to your inbox.
You are now subscribed
Your newsletter sign-up was successful
Want to add more newsletters?
Delivered Daily
Daily Newsletter
Sign up for the latest discoveries, groundbreaking research and fascinating breakthroughs that impact you and the wider world direct to your inbox.
Once a week
Life's Little Mysteries
Feed your curiosity with an exclusive mystery every week, solved with science and delivered direct to your inbox before it's seen anywhere else.
Once a week
How It Works
Sign up to our free science & technology newsletter for your weekly fix of fascinating articles, quick quizzes, amazing images, and more
Delivered daily
Space.com Newsletter
Breaking space news, the latest updates on rocket launches, skywatching events and more!
Once a month
Watch This Space
Sign up to our monthly entertainment newsletter to keep up with all our coverage of the latest sci-fi and space movies, tv shows, games and books.
Once a week
Night Sky This Week
Discover this week's must-see night sky events, moon phases, and stunning astrophotos. Sign up for our skywatching newsletter and explore the universe with us!
Join the club
Get full access to premium articles, exclusive features and a growing list of member rewards.
Climate change is melting ice, intensifying storms and bleaching coral reefs, and now, a new study suggests that it could also take a toll on babies' hearts.
The study, published yesterday (Jan. 30) in the Journal of the American Heart Association, suggests that, starting in 2025, extreme heat brought on by climate change could increase the number of babies born with heart defects in the United States. The greatest increase would be seen in the Midwest, followed by the Northeast and the South, researchers reported.
Congenital heart defects, or heart abnormalities that infants are born with, affect around 40,000 newborns every year in the U.S., according to a statement from the American Heart Association. [7 Ways Pregnant Women Affect Babies]
It's unclear why a pregnant woman's heat exposure can lead to a congenital heart defect in a baby, but animal studies suggest that heat could cause cell death in fetuses and interact with heat-sensitive proteins that are important in development, according to the statement.
An earlier study from the same group of researchers found that women's exposure to high temperatures during pregnancy was linked to an increased risk of congenital heart defects in babies. The study included women who gave birth between 1997 and 2007.
In this new study, the researchers combine that data with climate change temperature projections.
The team built upon climate change forecasts gathered by NASA and the Goddard Institute for Space Studies. They simulated changes in daily maximum temperatures for various geographic regions in the U.S. and calculated how much heat and extreme heat events pregnant women would be exposed to in the spring and summer.
Get the world’s most fascinating discoveries delivered straight to your inbox.
Between 2025 and 2035, they found that climate-change-driven heat events might spur an additional 7,000 cases of congenital heart defects, according to the statement. They found that most of these cases would be in the Midwest, followed by the Northeast and the South.
"Although this study is preliminary, it would be prudent for women in the early weeks of pregnancy to avoid heat extremes similar to the advice given to persons with cardiovascular and pulmonary disease during heart spells," senior author Dr. Shao Lin, an associate director of environmental health services with the University at Albany, State University of New York, said in the statement.
It's especially important for those planning to become pregnant or those who are three to eight weeks pregnant to avoid extreme heat, she said.
Live Science previously reported that pregnant women who are exposed to heat during early pregnancy can develop hyperthermia, or extremely high body temperature, which increases the risk of having babies with defects of the brain or spinal cord.
- 7 Foods Your Heart Will Hate
- 9 New Ways to Keep Your Heart Healthy
- Heart of the Matter: 7 Things to Know About Your Ticker
Originally published on Live Science.

Yasemin is a staff writer at Live Science, covering health, neuroscience and biology. Her work has appeared in Scientific American, Science and the San Jose Mercury News. She has a bachelor's degree in biomedical engineering from the University of Connecticut and a graduate certificate in science communication from the University of California, Santa Cruz.
