The impact of air pollutants on spontaneous abortion: a case-control study in Tongchuan City

Abstract

Objectives: Studies related to air pollutants and spontaneous abortion in urban northwestern China are scarce, and the main exposure windows of pollutants acting on pregnant women are unclear.

Study design: Case-control study.

Methods: Data were collected from pregnant women in Tongchuan City from 2018 to 2019. A total of 289 cases of spontaneous abortion and 1156 cases of full-term labor were included and analyzed using a case-control study. Logistic regression models were developed to explore the relationship between air pollutants and spontaneous abortion after Chi square analysis and Air pollutant description.

Results: O₃ (odds ratio [OR] = 1.028) is a risk factor for spontaneous abortion throughout pregnancy. PM_2.5 (OR = 1.015), PM₁₀ (OR = 1.010), SO₂ (OR = 1.026), and NO₂ (OR = 1.028) are risk factors for spontaneous abortion in the 30 days before the last menstrual period. PM_2.5 (OR = 1.015), PM₁₀ (OR = 1.013), SO₂ (OR = 1.036), and NO₂ (OR = 1.033) are risk factors for spontaneous abortion in the 30-60 days before the last menstrual period. PM_2.5 (OR = 1.028), PM₁₀ (OR = 1.013), SO₂ (OR = 1.035), and NO₂ (OR = 1.059) are risk factors for spontaneous abortion in the 60-90 days before the last menstrual period.

Conclusion: Exposure to high levels of air pollutants may be a cause of increased risk of spontaneous abortion, especially in the first trimester of the last menstrual period.

Keywords: Atmospheric pollutant; NO(2); O(3); PM(10); PM(2.5); SO(2); Spontaneous abortion.