Environmental Risk Factors For Autism Spectrum Disorders In Children

Objective:To explore the environmental risk factors in the children with autism spectrum disorder (ASD) during the pre-pregnant, pregnant, perinatal and postnatal raising period for further investigating the cause of autism spectrum disorder.Methods:Using the method of case-control,81 boys with ASD,74 boys with global developmental delay (GDD) and 163 boys with typical development were enrolled in the study. All subjects were investigated by author-designed questionnaire to obtain individual background information, family basic information, parents’ life styles and living environment, pre-and perinatal maternal medical history and environmental exposure, birth history and parenting environment after birth. All data were analyzed and compared between groups.Multiple sets of measurement data were compared with ANOVA, the counting data were compared with Chi-square test, and chi-square segmentation method were used between groups. Multivariate logistic regression were used to identify environmental risk factors for ASD and GDD.Results:Multi-factor logistic regression analysis shows that maternal occupational toxic exposure, maternal medical diseases and secondary smoking during pregnancy, children’s born place, fewer outdoor activities in the second year and less opportunities of communicating with peers were significantly related to ASD group. The OR value were 20.675、3.559、2.422.2.646、23.820、5.081(P<0.05), separately. Compared with ASD group, the paternal education years<6 was more in GDD group. Lower paternal education degree, maternal secondary smoking, vaginal infection or bleeding during pregnancy, fetal cord abnormality, newborn diseases, formula or mixed feeding within the first six months after birth, and fewer outdoor activities in the second year and less opportunities of communicating with peers were associated with GDD group(P<0.05).Conclusion:Maternal occupation toxic exposure, maternal medical diseases in pregnancy, lower level of the born place are possibly the specific risk factors related to ASD; while maternal secondary smoking during pregnancy, less opportunities for children communicating with peers, and less outdoor activities in the second year might be nonspecific risk factors associated with ASD. The investigation added the evidence that ASD develops under the interaction of gene and environmental factors.