SEATTLE, Wash – Researchers at the University of Washington have found another side effect of the wildfire smoke that often blankets the Pacific Northwest: a decline in sperm quality.
Researchers at UW Medicine found that wildfire smoke exposure may reduce key measures of sperm quality in patients undergoing fertility treatment.
The study analyzed samples from 84 men between 2018 and 2022.
Major wildfire smoke events happened in Seattle during that time frame.
“The team found consistent declines in sperm concentration, total sperm count, total motile (movement-capable) sperm count, and total progressively motile sperm count during wildfire smoke exposure,” UW Medicine said in a news release about the study. “One measure, the percentage of progressively motile sperm, showed a slight increase, though it was not enough to offset the overall reductions in sperm quality.”
UW Medicine says this aligns with similar studies led by Oregon Health Sciences University which linked air pollution and wildfire smoke to reproductive health.
“Although the study was not designed to evaluate the impact of wildfire smoke on reproductive outcomes, the pregnancy rate was 11% in the cohort of women with partners in this study, and the live birth rate was 9%, which tracks with similar rates previously published in literature and at the center,” the news release said.
“We are very interested in how and when sperm counts recover after wildfire smoke exposure,” Dr. Tristan Nicholson said. “Currently we are conducting a prospective pilot study of men in the Seattle area to evaluate how wildfire smoke affects sperm quality.”
You can read the full study here
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