One of the largest studies of its kind found that exposure to wildfire smoke increases the risk of preterm birth. Findings published American Journal of Obstetrics & Gynecology.
Researchers at Stanford University in Palo Alto studied hospitalization data for more than 2.5 million women between 2007 and 2012. They compared this information to daily estimates of wildfire smoke levels based on satellite imagery.
The data showed that, on average, women were exposed to smoke for 7 days. Wildfire smoke has been significantly associated with spontaneous preterm birth. Each additional day a pregnant woman was exposed to wildfire smoke slightly increased her chances of preterm delivery.
Scientists have noted that smoke from forest fires is more dangerous than many other air pollutants. Its particles can penetrate deep into the lungs and exacerbate asthma and heart disease. Smoke can travel hundreds or even thousands of kilometers from where the wildfire started. Now that forest fires are becoming more frequent, intense and widespread, it is necessary to find ways to protect vulnerable people, including pregnant women, from them.