A long-term study found that children who were in utero during Hurricane Sandy, the 2012 superstorm, had significantly increased risks for depression, anxiety and attention deficit and disruptive behavior disorders once they were preschool-age than their counterparts who were born before or conceived after the storm.
Ten years after the storm, the study published in the “Journal of Child Psychology and Psychiatry,” highlights the fact that we’re living in a world increasingly subject to extreme weather events due to climate change, which has a direct impact on women and children—especially those in underserved and marginalized communities.
It also elucidates what we already know about stress—that stress is its own form of toxin, regardless of what kind of prenatal vitamins you take or if you go to every prenatal yoga class. No matter how blissful you intend your pregnancy to be, stress creeps in, like a chill under the door. Whether those stressors are internal, like worrying about spotting or fetal movement, or external, like living through a natural disaster or a teetering economy, may not ultimately matter. To the body, stress is stress.
Stress in pregnancy is often outside of our control, but can have an outsized impact on our unborn babies’ development. The key? Finding ways to mitigate stress where and when you can.
Stress in pregnancy and the risk of psychiatric disorders
The study analyzed the development of 163 children ages 2 to 5 from diverse racial and economic backgrounds, 40.5% of whom were in utero during Sandy and 59.5% of whom were not.
After conducting interviews with the children’s parents and monitoring their health annually, and controlling for confounding factors such as additional family stress, researchers found that preschool girls who were exposed to Sandy in pregnancy were 20 times more likely to have generalized anxiety disorder and 30 times more likely to have depressive disorder compared to girls not exposed to the storm.
For boys who were exposed to Sandy in pregnancy, they were more than 60 times more likely to develop ADHD, and more than 20 times more likely to develop conduct disorder or 15 times more likely to develop oppositional defiant disorder.
The results are eye-opening. “We know for sure that in utero exposure to stress during pregnancy affects the mental health development of the child,” said Yoko Nomura, a psychology professor at the CUNY Graduate Center and Queens College and a lead author of the study, to The Washington Post. “We know the perinatal period is a very vulnerable time. What we didn’t know, though, is the magnitude of that impact, and I was really surprised that our sample had such a high prevalence of these disorders. I did not expect this to be so clear-cut.”
How stress impacts pregnancy
The study by Nomura and colleagues shows that extreme environmental events can directly impact population health and the health of the developing fetus, says Jill Goldstein, professor of psychiatry and medicine at Harvard Medical School and founder and executive director of the Innovation Center on Sex Differences in Medicine at Massachusetts General Hospital, to The Washington Post. “Depending on the timing of exposure, it can have a differential impact on the male and female brain … The authors use a natural experiment in a novel way to study [Sandy] and its impact on offspring psychiatric outcomes that differs by sex.”
While the relationship between stress and the developing fetal brain is not well understood from a physiological standpoint, emerging evidence suggests that high levels of neuroplasticity in the fetal brain makes it “particularly susceptible to environmental exposure of ‘nonoptimal’ levels of maternal distress,” write MacNeill, et al., in a separate study on stress fluctuations in pregnancy.
Stress is invisible, yet can wreak havoc in very palpable ways. In adults, it’s generally understood that chronically elevated levels of cortisol (the stress hormone) can impede how various other body processes function, including digestion and blood sugar metabolism, brain function and memory, blood pressure and sleep. There’s also a link between stress and depression.
In pregnancy, stress can seemingly pass directly through the placenta, comments Nomura. One study shows that stress may even be behind the development of gestational diabetes in some cases, thanks to an elevation of cortisol and an altered stress response in pregnancy paving the way to insulin resistance and blood sugar imbalance.
Additional studies have shown that high stress during pregnancy can have an impact on birth outcomes, leading to low birth weight and premature birth, while others have shown impacts on newborn babies’ emotions.
The study from MacNeill and colleagues found that babies of mothers who experienced more fluctuations in stress during pregnancy showed more fear, sadness and distress at 3 months than babies of moms who were less stressed. The infants were more likely to cry or fuss when left in a crib, be distressed when tired, and less trusting of adults they didn’t recognize.
High fluctuations in stress (known as stress lability) may mean that “individuals have more instability in their current life circumstances, or that those individuals might have a tendency to perceive their circumstances to be less stable or they have more difficulty regulating their emotions,” said lead study author Leigha MacNeill, research assistant professor of medical social sciences at Northwestern University’s Feinberg School of Medicine in Chicago, to CNN.
“More data is needed to determine what types and levels of stress impact the mother and her baby,” MacNeill said.
There are still a lot of unknowns. The link between stress in pregnancy and its effects on maternal and fetal health are worth exploring further, as these studies have shown. But it’s also important to remember that experts note some stress in pregnancy is normal, and some stressful events, like natural disasters, are completely out of our control.
That said, it’s exceedingly clear that “maternal health during pregnancy leads critically to population health—a theme that is quite relevant during these current political storms around women’s health,” says Goldstein.
What to do about stress in pregnancy
From mindfulness to playing music, breathwork to being in nature, we know, in theory, how to manage our stress levels in pregnancy and in other life phases. You likely don’t need ideas of *what* you need to do to stress less.
But implementing those practices regularly is a different story. It’s an especially different story when you’re pregnant, nauseated, exhausted and dealing with constant pain (back pain, round ligament pain, pelvic pain, mommy thumb), on top of your other life responsibilities (working, caring for other children, running a household, etc.).
That said, they do work, though of course, no amount of mindfulness or yoga can prevent a natural disaster from occurring. But people aren’t going to stop getting pregnant just because natural disasters are continuing to happen, notes Nomura. “So we have to find a way to make it easier for society to have better-functioning children in the future.”
She hopes her research will “help guide what is going to happen, so that we will be able to come up with better planning, better intervention, better infrastructure.”
What might help in the meantime is reframing how we view the stress we can control in pregnancy. Pregnancy is stressful. Is there any other way to view this life stage, which is marked by rapid change and growth and all-encompassing transitions?
Recognizing this simple fact might make it easier to protect yourself from other external stressors during the prenatal period. That might look like saying no to certain social obligations, assembling a birth care team you trust and can easily reach out to for questions, taking your full parental leave at work, and keeping your circle slightly smaller.
If nothing else, the research highlights that mental health during pregnancy is just as important as physical health, for both you and your baby. And that protecting your mental health where you can by limiting stress should be an equally important priority.
Feng Y, Feng Q, Qu H, et al. Stress adaptation is associated with insulin resistance in women with gestational diabetes mellitus. Nutr. Diabetes 10, 4 (2020). doi:10.1038/s41387-020-0107-8
MacNeill LA, Krogh‐Jespersen S, Zhang Y, Giase G, Edwards R, Petitclerc A, Mithal LB, Mestan K, Grobman WA, Norton ES, Alshurafa N. Lability of prenatal stress during the COVID‐19 pandemic links to negative affect in infancy. Infancy. 2022 Sep 7. doi:10.1111/infa.12499
Nomura Y, Newcorn JH, Ginalis C, Heitz C, Zaki J, Khan F, Nasrin M, Sie K, DeIngeniis D, Hurd YL. Prenatal exposure to a natural disaster and early development of psychiatric disorders during the preschool years: stress in pregnancy study. Journal of Child Psychology and Psychiatry. 2022 Sep 21.
Yang L, Zhao Y, Wang Y, et al. The effects of psychological stress on depression. Curr Neuropharmacol. 2015;13(4):494-504. doi:10.2174/1570159×1304150831150507