Maternal air pollution exposure during the first trimester of pregnancy and markers of inflammation and endothelial dysfunction.

Background: Maternal exposure to air pollutants has been associated with pregnancy complications and adverse birth outcomes. Endothelial dysfunction, an imbalance in vascular function, during pregnancy is considered a key element in the development of pre-eclampsia. Environmental exposure to particulate matter (PM) during the first trimester of pregnancy might increase maternal inflammatory status thus affecting fetal growth, possibly leading to preterm delivery.
Objectives: The purpose of the study was to evaluate possible effects of PM ₁₀ and PM _2.5 exposure on fetal growth in healthy pregnant women at the end of the first trimester of pregnancy by investigating the relationship between circulating biomarkers of inflammation (IL-6), early systemic prothrombotic effects (CRP, plasma fibrinogen, PAI-1) and endothelial dysfunction (sICAM-1 and sVCAM-1).
Methods: 295 pregnant women were recruited. Individual PM exposure was assigned to each subject by calculating the mean of PM ₁₀ and PM _2.5 daily values observed during the 30, 60, and 90 days preceding enrolment (long-term) and single lag days back to fourteen days (short-term), and circulating plasma biomarkers were determined.
Results: For long-term exposure, we observed an increase in sVCAM-1 and a decrease of PAI-1 levels for each 10 μg/m ³ increase in PM ₁₀ concentration. Decreases in IL-6 and CRP levels were associated with each 10 μg/m ³ PM _2.5 increase. For short-term exposure, the levels of sVCAM-1 and PAI-1 were found to be associated with PM ₁₀ exposure, whereas fibrinogen levels were associated with PM _2.5 exposure. Maternal plasmatic fibrinogen levels were negatively associated with the crown-rump length (p-value = 0.008).
Discussion: The present study showed that both long- and short-term exposures to PM are associated with changes in circulating levels of biomarkers in pregnant women reflecting systemic inflammation and endothelial dysfunction/activation. Our findings support the hypothesis that inflammation and endothelial dysfunction might have a central role in modulating the detrimental effects of air pollution exposure during pregnancy.
(Copyright © 2022. Published by Elsevier Inc.)