Witnessing a natural disaster can take a serious toll on a person’s mental health. New research suggests that’s also true for fetuses who experience those disasters in utero.
It’s the latest sign that climate disasters — which are becoming more frequent and severe as the planet warms — are threatening health, and that even unborn babies are highly vulnerable.
The findings, published in the Journal of Child Psychology and Psychiatry on Wednesday, show that children who were in the womb during 2012′s devastating Superstorm Sandy were at “substantially increased risk” of developing depression and anxiety, as well as attention deficit and disruptive behavior disorders, in early childhood.
Scientists have long known that maternal stress during pregnancy can threaten a child’s mental health, said Yoko Nomura, a psychology professor at the CUNY Graduate Center and Queens College in New York, who led the study. Still, she said, she found the results “alarming.
“I was really surprised,” she said.
Hurricane Sandy was a powerful climate change-fueled storm that devastated Jamaica and a swath of Latin America before careening northward and slamming into the U.S. East Coast. The storm killed 44 in New York and inflicted an estimated $19 billion in damage.
Nomura was leading a study in New York City on the effects of psychosocial stress during pregnancy at the time the storm hit. She knew then she had to investigate Sandy’s implications, so she quickly pivoted.
For the report, Nomura and other researchers from the City University of New York Graduate Center and the Icahn School of Medicine at Mount Sinai analyzed 163 preschool-aged children in New York City whose mothers had lived in parts of New York City that Sandy hit particularly hard. The researchers examined the childrens’ health records and interviewed their parents each year after the storm. Sixty-six of the children were in the womb during the hurricane; the remaining 97 were born before the storm or were not yet conceived.
Each of the 163 children’s parents experienced some form of trauma due to Sandy, Nomura said. Half were forced to evacuate in the storm’s wake, and another tenth evacuated before it touched down. The remaining participants opened their homes to others displaced by the storm. Participants detailed other stressors such as damages to their homes and neighborhoods, trouble with insurance companies, power outages, and weeks of lost income following the storm.
The discrepancies were striking. Fifty-three percent of the children exposed to Hurricane Sandy while in the womb exhibited clear signs of an anxiety disorder, versus just 22 percent of children who weren’t. And some 30 percent of the exposed group tested for attention deficit or disruptive behavior disorders, compared with just over 8 percent of those who weren’t.
One puzzling result from the new study: Mental disorders varied by biological sex. Specifically, the researchers found that female children exposed to Sandy were at far higher risk of developing anxiety disorders, while exposed males were at increased risk for attention deficit and disruptive behavioral disorders.
The new research is part of a growing body of work on the risks the climate crisis poses to fetuses and pregnant people. A 2019 paper found that pregnancy complications increased nearly 17% shortly after Sandy, with the highest increases among uninsured people and people of color. Other recent studies have also linked extreme heat to gestational diabetes, premature birth, and increased rates of stillbirth and low birth weight. And last summer, the American College of Obstetricians and Gynecologists issued guidance on the link between extreme temperatures and irregular birth outcomes.
New research is also bringing the mental health effects of climate change into sharper focus. In February, a landmark report from the world’s top climate science body highlighted that toll for the first time, forecasting increased rates of anxiety and stress as the planet continues to warm.
Ari Bernstein, a Boston-based pediatrician who directs Harvard University’s Center for Climate, Health and the Global Environment and who didn’t work on the paper, said the new study pushes those findings forward.
“We strangely believe that disasters wrought by climate change matter only in the moment they occur,” he said. “These findings bring a harsh correction to that misbelief.”
In some ways, the new report raises as many questions as it answers. It can’t tease out a causal connection between fetal hurricane exposure and mental health problems, Nomura said. It can’t determine if the results can be extrapolated to other natural disasters. And, importantly, it doesn’t explain the mechanisms behind its own results.
“What is most baffling about it, what’s still unanswered by the study, is the ‘why,’” said Dr. Jeffrey Newcorn, director of the Division of ADHD, Learning Disabilities and Related Disorders at the Icahn School of Medicine at Mount Sinai and a co-author of the study, said. “Why does this happen? What are the mechanisms through which this kind of stress exposure produces these kinds of outcomes? What can we do to mitigate this?” These questions are all still left open.
But the study is a window into the strange and frightening ways climate disasters can threaten wellbeing, which is especially important as disasters are becoming more frequent and severe as the planet warms.
Newcorn said he hopes the work will encourage more research — and funding for research — into how climate-related events are exacerbating prenatal maternal stress.
And Amruta Nori-Sarma, assistant professor in the Environmental Health Department at Boston University School of Public Health, who did not work on the study, said she hopes it spurs more assistance to at-risk populations.
“The study demonstrates the need to provide additional services to vulnerable populations when extreme weather conditions are predicted, including services targeting pregnant women and neonates,” she said.
The findings come amid growing concern about the impact of climate disasters on young people’s mental health. On Thursday morning, advocates from the advocacy organization Moms Clean Air Force joined with federal representatives and youth organizers for a press conference endorsing a federal legislative proposal aiming to boost funding for resources to support the mental health of young people affected by climate change.
Still, “the life-long consequences of adverse experiences in utero are often underestimated,” Taylor Morris, a senior fellow at the The Health Policy Partnership, who has written about the risks climate change poses to fetal health and did not work on the study. She hopes the study helps change that, she said.
Dharna Noor can be reached at firstname.lastname@example.org. Follow her on Twitter @dharnanoor.