[Effect of air pollution on pregnancy outcome of women at reproductive age in Xi'an, 2010-2013].

Objective: To compare the differences in the incidence of adverse pregnancy outcome in different area, and confirm if the incidence of adverse pregnancy outcomes is closely associated with air pollution. Methods: A cross-sectional study was conducted in the central urban area and the rural-urban area of Xi'an through a questionnaire survey conducted among the local reproductive women selected through multistage stratified random sampling during 2010-2013, all the reproductive women surveyed were in pregnancy or had definite pregnancy outcomes. Results: The annual average of SO2 concentration in the central urban area was 38-54 μg/m(3), higher than that in the rural-urban area (29-43 μg/m(3)). The annual average NO2 concentration in the central urban area was 29-87 μg/m(3), higher than that in the rural-urban area (22-42 μg/m(3)). The incidence of birth defects was higher in the central urban area than in the rural-urban area (2.1% vs. 1.0%), the difference was significant (P<0.05). After adjusting for confounding factors, logistic regression analysis showed the incidence of birth defects in the central urban area was still significantly higher than that in the rural-urban area, the difference was significant (P<0.05). Conclusion: The incidence of adverse pregnancy was closely associated with the level of air pollution.