Abstract
BACKGROUND: Maternal exposure to ambient air pollution has been associated with an increased risk of congenital heart defects in offspring; however, the results are inconsistent. OBJECTIVES: We investigated whether there is an association between prenatal exposure to particulate matter with diameter ≤10μm (PM(10)) during early pregnancy and fetal cardiovascular malformations. METHODS: The gravidae from a hospital-based case–control study in Fuzhou, China, during 2007–2013 were assigned 10-d or 1-mo averages of daily PM(10) using an air monitor–based inverse distance weighting method during early pregnancy. A total of 662 live-birth or selectively terminated cases and 3,972 live-birth controls were enrolled. The exposure was considered as a categorical variable. A multivariable logistic regression model was constructed to quantify the adjusted odds ratios (aORs) of the exposure to PM(10) and the risks of fetal cardiovascular malformations. RESULTS: PM(10) levels were positively associated with the risks of atrial septal defect (aORs ranging from 1.29 to 2.17), patent ductus arteriosus [aORs = 1.54, 1.63; 95% confidence intervals (CIs): 1.17, 2.23; 1.06, 3.24], overall fetal cardiovascular malformations (aOR = 1.28; 95% CI: 1.03, 1.61), ventricular septal defect (aOR = 1.19; 95% CI: 1.00, 1.43), and tetralogy of Fallot (aOR = 1.44; 95% CI: 1.01, 2.19) in the various observed periods scaled by 10 d or 1 mo in the first and second gestation months. The strongest associations were observed for exposure to PM(10) in the second quartile, whereas the associations were attenuated when higher concentrations of PM(10) in the third and fourth quartiles of the exposure were evaluated. No correlations of PM(10) levels with these cardiovascular malformations in the other time periods of gestation were observed. CONCLUSIONS: Our findings suggest some positive associations between maternal exposure to ambient PM(10) during the first two months of pregnancy and fetal cardiovascular malformations. https://doi.org/10.1289/EHP289.