Choe SA, et al. - Using a population-representative cohort, researchers evaluated the association between ambient concentrations of 5 major air pollutants (particulate matter ≤10 μm in diameter (PM10), nitrogen dioxide (NO₂), carbon monoxide (CO), sulfur dioxide (SO₂), and ozone (O₃)) during preconceptional and prenatal periods and 3 hypertensive disorders of pregnancy in Seoul, Korea. Among the Korean general population, exposure to some air pollutants before and during pregnancy was positively associated with hypertensive disorders of pregnancy.