Abstract
OBJECTIVES: This study aimed to investigate the association between low-level air pollution and adverse pregnancy outcomes, assess the potential mediating role of healthy lifestyle, and identify key modifiable behaviors.</p>
STUDY DESIGN: Case-control study.</p>
METHODS: This study included a total of 231,331 female participants from the UK Biobank. A healthy lifestyle score was established based on non-smoking, moderate drinking, healthy diet, regular physical activity, and ideal BMI. Multivariable logistic regression model was used to explore the associations between low-level air pollution, healthy lifestyle and adverse pregnancy outcomes. The eXtreme Gradient Boosting (XGBoost) and SHapley Additive exPlanations (SHAP) were employed to elucidate the relative importance of these modifiable behaviors.</p>
RESULTS: Each 1 μg/m3 increase in PM2.5, PM10, NO2, and NOx was associated with an increased risk of low offspring birthweight. The odds ratios (95 % CI) were 1.046 (1.025-1.068) for PM2.5, 1.015 (1.004-1.027) for PM10, 1.007 (1.004-1.009) for NO2, 1.003 (1.002-1.005) for NOx. No significant associations were found between low-level air pollution and other adverse pregnancy outcomes. Participants with unfavorable lifestyle and higher low-level air pollution had the highest risk of low offspring birthweight. In the modeling study, a healthy diet, and ideal BMI were identified as main modifiable behaviors.</p>
CONCLUSIONS: Low-level air pollution was still associated with reduced offspring birth weight. Adopting a healthy lifestyle, especially healthy diet, and ideal BMI, could help mitigate the risks of air pollution. These findings provide evidence to support integrated interventions that combine environmental regulation with lifestyle modification programs to reduce adverse pregnancy outcomes effectively.</p>