SEATTLE — This story was originally posted on MyNorthwest.com
With wildfires still burning in Washington, a new study is shedding light on the risk that pollution from those fires poses to pregnant women and their babies.
“We found there was a higher risk of pre-term birth with higher exposure to wildfire smoke,” Dr. Catherine Karr said in an interview provided by UW Medicine.
Karr was one of 42 researchers involved in the nationwide study, which examined 20,000 births from 2006 to 2020.
“Virtually all the women had at least one day with some smoke — some small particles from wildfire smoke,” Karr said.
The timing of when a woman is exposed to smoke during her pregnancy appears to play a role.
Exposure to high concentrations of smoke-days late in a pregnancy showed the strongest association to pre-term births, but so did exposure to lower and moderate levels of smoke-days during the second trimester.
“The second trimester is a period in pregnancy which sees the richest and most intense growth of the placenta,” Karr said in a statement.
Wildfire smoke can interfere with development of placenta
Researchers theorize that the tiny, inhaled smoke particles can enter a woman’s bloodstream and interfere with the development of the placenta.
She said pregnant women need to be aware of the risk and take precautions, particularly in the western half of the U.S., where researchers saw the highest risk.
“Learn about the air quality index or AQI, which is a really handy way of knowing whether the air quality is safe,” Karr said.
She said you can find the AQI on the Environmental Protection Agency’s website and even download an app on your phone.
Researchers suggest local public health departments provide early warnings about smoke events as well as access to clean air, indoor locations.
Read more of Heather Bosch’s stories here.
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