Progestational And Gestational Risk Factors Of Sub-threshold Autism Trait In Pre-school Children:a Birth Cohort Study

ObjectiveTo describe the prevalence of sub-threshold autism trait(SAT) in pre-school children and to explore its progestational and gestational risk factors. MethodsThe participants of this study were from China-Anhui Birth Cohort study(C-ABCS) recruited between October 2008 and October 2010. A total of 4 669 singleton live births were observed in this cohort. These infants were further followed up during April 2014 to April 2015 and 3 663 data from 3 803 pre-school children were put into final analysis, mothers’ demographic data, as well as progestational and gestational information were collected by women’s self-reported questionnaires during their routine antenatal checkups. The following indicators were involved in the questionnaires: 1. maternal demographic information, including age, height, residence and education level; 2. maternal medical history and history of pregnancy, including abortions, adverse childbirths, hyperthyroidism/ hypothyroidism, hypertension, diabetes, heart failure; 3. maternal exposures to occupational and living environement, such as use of chemical daily necessities and household appliances, noises in living and working environment, occupational exposures to heavy metals in, folic acid use, passive tobacco use; 4. general conditions of the index pregnancy, including pregnancy expectations, use of assisted reproductive technologies, vaginal bleeding, vomiting and fevers during pregnancy; 5. maternal mental health, such as assessment of stressful events, depression, anxiety and pregnancy-specific anxiety. SAT was screened by parents, records using Clancy Autism Behavior Scale. Chi-square test was used to compare the difference of SAT rate in different demographic characteristics and various environmental exposures. Binary regression model was used to analyse the associations between exposures and SAT in preschool children. ResultsA total of 290 cases of SAT were screened out, and the prevalence was 7.9%. Univariate analysis suggested that parental low educational level, maternal heart failure, vomiting in the 1st trimester of pregnancy, insufficient weight gain during pregnancy, progestational and gestational exposure to noisy living environment, lead exposure in the 1st trimester of pregnancy, progestational cadmium exposure, use of hair dryer in the 1st and 2nd trimester of pregnancy, use of microwave oven the 1st trimester of pregnancy, stressful events and maternal mood disorders(anxiety, depression, pregnancy-specific anxiety) were risk factors of SAT in preschool children. After controlling maternal age, maternal education and residence,binary logistic regression analysis showed that high educational level of mother was protective factor of SAT. Insufficient weight gain during pregnancy(OR=1.543, 95%CI 1.095, 2.175), microwave oven use(OR=1.332, 95%CI 1.046, 1.697) in the 1st trimester of pregnancy, lead exposure in the 1st trimester of pregnancy(OR=2.211, 95%CI 1.359, 3.597) were risk factors of SAT in preschool children. Maternal anxiety(OR=3.616, 95%CI 1.305, 10.015), depression(OR=2.667, 95%CI 1.207, 5.889) and pregnancy-related anxiety(OR=2.056, 95%CI 1.394, 3.033) were risk factors of SAT. ConclusionMaternal insufficient weight gain during pregnancy is risk factor of SAT in preschool children. Pregnant women should rationally control body weight during pregnancy and keep away from excessive weight gain and inadequate weight gain. Women must avoid the noisy environment and electromagnetic radiation, or use appropriate protective measures. At the same time, pregnant women should learn to regulate emotions to protect their own health and to create a favorable environment for the fetus.