Background: Children of depressed mothers have elevated conduct problems, presumably because maternal depression disrupts the caregiving environment. Alternatively, the association between maternal depression and children's antisocial behavior (ASB) may come about because (1) depressed women are likely to have comorbid antisocial personality traits, (2) depressed women are likely to mate and bear children with antisocial men, or (3) children of depressed mothers inherit a genetic liability for psychopathology.
Method: We used data from the E-Risk Study, a representative British cohort of 1116 twin pairs assessed at 5 and 7 years of age. We tested for environmental mediation of the association between maternal depression during the children's first 5 years of life and children's ASB at age 7 years, free from familial liability for ASB.
Results: Maternal depression occurring after, but not before, the twins' birth was associated with child ASB and showed a significant dose-response relationship with child ASB at 7 years of age. Parental history of ASPD symptoms accounted for approximately one third of the observed association between maternal depression and children's ASB, but maternal depression continued to significantly predict children's ASB. Intraindividual change analyses indicated that children exposed to their mother's depression between ages 5 and 7 years showed a subsequent increase in ASB by age 7 years. The combination of depression and ASPD symptoms in mothers posed the greatest risk for children's ASB.
Conclusions: Studies ignoring genetic transmission overestimate social transmission effects because both genetic and environmental processes are involved in creating risk for ASB in children of depressed mothers. Interventions for depressed mothers aiming to reduce conduct problems in their children should address parents' antisocial personality, as well as mothers' depression.