NEW Research on Climate Change & Birth Outcomes

Last September, JAMA Network Open (JNO), the online, open-access version of one of the country’s most highly regarded medical journals, put out a “call for papers” about the health impacts of climate change.  They noted a particular interest in research on vulnerable groups, such as “people at the extremes of age, those with chronic illness, those performing physical work in the heat, and those living with homelessness, poverty, food insecurity, and discrimination.”

With reference to the “extremes of age,” children had been the focus of a detailed paper about health and climate change from the American Academy of Pediatrics in October 2015 and the American College of Obstetrics and Gynecology had a brief online statement about women’s health and climate change that mentions risks to pregnancy outcomes.  However, despite numerous articles in the medical literature looking at various climate impacts and pregnancy, there have been very few reviews looking at the “big picture”: does climate change affect pregnancy and birth outcomes?

Today, June 18, our article appears in JAMA Network Open. It is the first large-scale review analyzing the connection between common, ongoing climate-related exposures and birth outcomes.  From nearly 70 studies conducted between 2007 and 2018 across the US, we find a very strong association between

exposure to heat or climate-related air pollutants (ozone and fine particulate matter) and premature birth, low birth weight and stillbirth.   These investigations looked at over 30 million births, with a mean over 560,000 births/study and utilized a wide variety of analytic approaches; 57 of the 68 studies (84%) found a statistically significant connection between these widespread exposures and outcomes.  Strong evidence of biological plausibility exists, suggesting that these associations are not random, but are likely cause and effect.

These birth outcomes have serious consequences.   Certainly stillbirth, the death of a fetus in utero, is a catastrophic event for any pregnant woman and her family.  In addition, both premature and low birth weight infants have an increased risk of dying in the first year of life as well as significant health challenges in childhood and even into adult life.   Two sub-populations appeared to be at even higher risk: women with asthma and Black mothers.  Slightly more than half of the studies showed evidence of higher risk for pregnancy in minority women, with Black mothers identified more than twice as often as Latinas.

My background is as a practicing obstetrician delivering babies, not writing academic papers.  Putting this research together was only possible because my activism led me to enlist three superb academic scientists/physicians.  We found a shared belief that if climate change was already harming pregnancies here in the US, it was vitally important information the public would want to know.

At this moment in history, it is difficult to draw focus away from our dual crises of COVID and racial injustice.   However, one positive aspect of this time has been the vivid reminder of how much our lives are connected.  People have adapted quickly, wearing masks and distancing, to help protect not only themselves but complete strangers.  As our paper enters the public sphere with free and open access, we invite you to read, comment, and join us in sharing the message that the “vulnerable group” most deserving of our protection is our mothers and their children.  We must do whatever it takes to save future generations from the preventable suffering of the Climate Crisis.

Bruce Bekkar, MD, is a member of the Climate for Health Leadership Circle. He was a guest on a recent episode of ecoAmerica’s Let’s Talk Climate webcast series, “Motherhood in a Changing Climate: Pregnancy & Birth Outcomes.”

Additional news coverage of this new research:

“Climate Change Tied to Pregnancy Risks, Affecting Black Mothers Most” in The New York Times

“Climate crisis poses serious risks for pregnancy, investigation finds” in The Guardian

“Climate Change, Smog Could Mean More Preemie Babies: Study” in U.S. News & World Report