A new study has found that poor air quality can affect pregnant women. It can lead to a number of adverse effects including preterm birth.
The study was published in the journal, 'American Journal of Obstetrics & Gynecology'.
Wildfire smoke is especially harmful to people's health because it contains extremely fine particles that can enter deep into the lungs and may worsen medical conditions such as asthma and heart disease. These tiny particles can also travel hundreds and sometimes thousands of miles from the wildfire's point of origin.
Researchers reviewed birth certificates and hospital delivery data from 2007-2012 of more than 2.5 million pregnant people in California. They compared that information with daily estimates of wildfire smoke intensity -- based on satellite images -- by zip code.
Data revealed that four weeks prior to conception through the first 20 weeks of pregnancy, 86 percent of pregnant individuals were exposed to at least one day of wildfire smoke, with an average exposure of 7.5 days. Results showed that wildfire smoke was significantly associated with spontaneous preterm birth, and each additional day a pregnant person was exposed to wildfire smoke slightly increased the odds of delivering an infant prematurely.
"Wildfires lead to acute and abrupt changes in air quality," says the study's lead author Anne Waldrop, MD, a maternal-fetal medicine subspecialist fellow at Stanford University in Palo Alto, Calif. "And some emerging evidence suggests that wildfire smoke could be worse for your health than other types of pollutants. So, even as we work to decrease other forms of air pollution, with wildfires becoming more frequent, more intense, and happening on a much larger scale, exposure to wildfire smoke is a serious public health problem, especially for vulnerable populations like pregnant people."
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