Relationship between exposure to air pollutants in the first trimester and spontaneous abortion in pregnant women in the river valley city

Purpose The relationship between exposure doses of 2.5-micrometer Particulate Matter (PM_2.5), Inhalable particles (PM₁₀), Sulfur Dioxide (SO₂), Nitrogen Dioxide (NO₂) and Ozone (O₃) in the first trimester and spontaneous abortion of pregnant women was evaluated by global average method and nearest monitoring station method, respectively. Method Retrospective analysis of the clinical data of pregnant women with spontaneous abortion and full-term pregnant women in the Department of Obstetrics and Gynecology of two third-class hospitals in a valley city in Northwest China. According to the age factor, the eligible pregnant women were matched at a ratio of 1 : 4. The global average method and the nearest monitoring station method were used to evaluate the exposure of pollutants. The rank-sum test and conditional logistic regression were used to analyze the correlation between air pollutants and spontaneous abortion. Results Although the global average method and the nearest monitoring station method are slightly different in the assessment of exposure dose, they do not affect the correlation evaluation with spontaneous abortion. The exposure of pregnant women to PM_2.5(OR₁ = 1.156, OR₂ = 1.036), SO₂ (OR₁ = 1.432, OR₂ = 1.429) and NO₂ (OR₁ = 1.121, OR₂ = 1.159) in the first trimester is related to the occurrence of spontaneous abortion.(OR₁: the global average method, OR₂: the nearest monitoring station method) Conclusion The exposure of PM_2.5, SO₂ and NO₂ in the first trimester in valley cities is associated with the occurrence of spontaneous abortion in pregnant women.