A report from the Centers for Disease Control and Prevention (CDC) found that the rate of preterm births rose by 12 percent nationally between 2014 and 2022. 

Manisha Gandhi, chair of the American College of Obstetricians and Gynecologists Clinical Practice Guidelines Committee, told The Hill’s Alejandra O’Connell-Domenech that several factors could be at play. 

“We are seeing more patients with obesity, higher risks for hypertension or preeclampsia … seeing more diabetes,” Gandhi said. “Potentially some of those risk factors that lead to earlier delivery could be playing a role.” 

Environmental factors such as exposure to hormone-disrupting chemicals and air pollution may also be contributing to the rise in preterm births. 

Leonardo Trasande, head of New York University’s Center for Environmental Hazards, noted that microplastic exposure, including from the air, may be involved. A 2016 study estimated about 3 percent of preterm births could be attributed to exposure to particles making up air pollution. 

“An increasing amount of those particles actually are from plastics,” Trasande told The Hill. “So, there actually is some connection between the older findings and the newer findings.”   

Preterm births are defined by those that occur before 37 weeks of pregnancy, accounting for roughly 1 in 10 births in the U.S., according to the March of Dimes.  

The health effects of premature births on infants are more severe the earlier an infant is born. These can range from developmental delays, asthma or neurological conditions.