Late-pregnancy air pollution exposure and neonatal anthropometry with and without gestational hypertension

This study examined the relationships among gestational hypertension (GH), peridelivery inflammatory biomarkers, late-pregnancy air pollution exposure, and neonatal anthropometric outcomes. Pregnant women recruited during the second trimester were classified into the GH or normotensive group. Maternal characteristics, blood pressure, high-sensitivity C-reactive protein (hs-CRP), interleukin 1β (IL-1β), tumor necrosis factor-α (TNF-α), and neonatal outcomes were assessed. Exposure to PM₁₀, PM_2.5, NO₂, SO₂, carbon monoxide (CO), and ozone (O₃) during the 30 days before delivery was estimated using ambient monitoring data. Women with GH had higher maternal hs-CRP concentrations and delivered neonates with lower birth weight and smaller chest and abdominal circumferences. PM_2.5, NO₂, SO₂, and CO exposures were inversely associated with birth length. Mediation analyses showed no significant indirect effects through hs-CRP, IL-1β, or TNF-α, although maternal and cord blood TNF-α concentrations were positively correlated. These findings indicate that GH and late-pregnancy air pollution exposure are associated with less favorable neonatal anthropometric outcomes through pathways not explained by the measured circulating inflammatory biomarkers.