How much and why does the mum matter? Mechanisms explaining the intergenerational transmission of smoking

Offspring whose mother smokes during pregnancy have higher risk of smoking themselves. In this study, epigenetics, antisocial behaviours, and social learning were investigated as potential mechanisms of mother-to-child transmission of smoking among a population sample drawn from the Birth Cohort Study 1970. Findings on daughters showed that the direct epigenetic hypothesis was mediated by social learning mechanisms, suggesting that exposure to maternal smoking across childhood and adolescence strongly explained why the smoking habits of mother and daughter correlate. However, prenatal smoking effects on sons were only partially explained by observational learning of mother smoking habits. Our estimates provided evidence concerning the potential role also played by the child's persistent antisocial behaviours. These results were confirmed after controlling for early life circumstances and current socioeconomic conditions. Policy implications of the results are discussed