Associations between maternal exposure to particulate matter (≤10 microns) and congenital anomalies in Liaoning Province, China: A case-control study (2010–2015)

Background: A growing number of reports suggest that maternal exposure to ambient air pollution is a potential risk factor for congenital anomalies (CAs). However, most studies have focused on specific CAs, especially congenital heart defects, while relatively few have investigated the effects of exposure to particulate matter of ≤10 microns (PM10) on CAs overall, but with inconsistent results. This study aims to investigate the associations between maternal exposure to PM10 and the risks of CAs in offspring in Liaoning Province. Methods: Cases of CAs (n = 31,407) and controls (n = 7,958) were selected from the Maternal and Child Health Certificate Registry of Liaoning Province from 2010 to 2015. PM10 concentrations were obtained from the Environment Protection Bureau in the same region. A multivariable logistic regression model combined with variables was used to analyze the association between maternal PM10 exposure and the risks of CAs. Results: Exposure to higher levels of PM10 significantly increased the risks of CAs. In adjusted model I, the odds ratio (OR) of moderate and severe exposure at 3 months before pregnancy was 1.25 (95% confidence interval [CI] = 1.11–1.40) and 1.40 (95% CI = 1.25–1.57), respectively. In the first trimester, the OR of moderate and severe exposure was 1.27 (95% CI = 1.12–1.44) and 1.71 (95% CI = 1.16–1.93), respectively. Conclusions: Maternal exposure to PM10 was significantly associated with increased risks of CAs in Liaoning Province from 2010 to 2015. Pre-pregnancy (3 months) and the first trimester were identified as potential windows of susceptibility.