Objective：To explore the risk factors of congenital heart disease（CHD） and to provide references for research in the etiol－ogy of CHD and its scientific precautions. Methods：A hospital-based CHD 1∶1 matched case-control study was conducted. Patients were diagnosed by echocardiogram，cardiac catheterization or surgery and controls with no congenital disease were selected at the corresponding period. Children’s parents were interviewed with a unified face-to-face questionnaire. All factors were analyzed by univariate and multivariate conditional Logistic regression；risk factors associated with CHD were screened out. Results：Information of 260 pairs of children with CHD and controls were analyzed. All factors were analyzed by univariate Logistic regression at a=0.05 level and 21 suspected risk factors were initially screened out then multivariate conditional Logistic regression was used to do multi－variate comprehensive analysis. Results indicated that maternal age（>35 years：OR=3.075，P=0.010；<20 years：OR=5.084，P=0.012），passive smoking（small amount：OR=1.728，P=0.040；large amount：OR=3.903，P=0.000） and catching a cold in early pregnancy（OR=1.787，P=0.023） were the risk factors of CHD；taking folic acid regularly（OR=0.447，P=0.004） and eating meat（≥4 times/week：OR=0.293，P=0.001；1-3 times/week：OR=0.372，P=0.008） were significantly associated with a reduced risk for CHD. Conclusions：The first trimester is a critical period of fetal heart development. Mother old or young，exposuring to tobacco and catching a cold in early pregnancy are at increased risk for giving birth to a child with CHD；taking folic acid regularly and eating more meat are associated with a reduced risk for CHD.
