Interaction between parental preconception and prenatal smoking and alcohol use on autism-like behaviour in preschoolers: a cross-sectional study in Huizhou, China.

This study looked at nearly 20,000 preschoolers in China to see if parents' smoking and drinking habits affected their children's autism-like behaviours. Children whose mothers were exposed to secondhand smoke during pregnancy, or whose fathers had a history of smoking, were more likely to show autism-like behaviours. The research suggests that avoiding smoking and secondhand smoke during pregnancy may help reduce autism risk.

This large cross-sectional study of 19,089 Chinese preschoolers (ages 3-6) examined associations between parental smoking and alcohol use before/during pregnancy and autism-like behaviours. The study found that maternal prenatal passive smoking exposure increased autism-like behaviour risk by 32.7%, while paternal smoking history increased risk by 64.3%. Interestingly, among mothers with pre-pregnancy smoking history, those who quit smoking during pregnancy but continued alcohol consumption showed a complex negative interaction effect. The findings suggest parental tobacco exposure represents a modifiable risk factor for autism spectrum behaviours, though the observational design limits causal inference.

Findings support recommending smoking cessation and avoiding secondhand smoke exposure during pregnancy as potential autism prevention strategies. Healthcare providers should counsel both parents about smoking risks. However, causal relationships require confirmation through prospective studies.

Cross-sectional design prevents causal inference. Relies on parental self-reporting of substance use, which may be subject to recall bias or social desirability bias. Study limited to one Chinese region, potentially limiting generalizability to other populations.

This study aimed to investigate the associations between preconception and prenatal smoking and alcohol consumption and the risk of autism-like behaviour in preschool children, with the aim of providing evidence for early prevention strategies. This cross-sectional study included 19,089 children aged 3-6 years from 111 kindergartens in Huicheng District, Huizhou City, Guangdong Province, China, between June 2022 and June 2023. Logistic regression was used to analyse the associations between parental smoking, drinking and autism-like behaviour in children. Multiplicative and additive interaction models were applied to evaluate the interaction between smoking and drinking on autism-like behaviour in children.

Compared with the unexposed group, children with maternal prenatal passive smoking exposure (OR = 1.327, 95% CI: 1.042 to 1.690) and those with a paternal history of smoking (OR = 1.643, 95% CI: 1.036 to 2.605) exhibited significantly higher odds of autism-like behaviour. Among mothers with a prepregnancy smoking history, a significant negative additive interaction was observed between smoking cessation during pregnancy and concurrent alcohol consumption (RERI = -2.170, 95% CI: -4.035 to -0.304). This study identifies prenatal exposure to parental smoking-both maternal passive smoking and paternal smoking history-as a significant risk factor for autism-like behaviour in preschoolers. The finding of a negative additive interaction between maternal smoking cessation and concurrent alcohol consumption underscores the complexity of modifying health behaviours.

These findings emphasise the key role of reducing parental tobacco and alcohol exposure in the primary prevention of autism spectrum disorder.