In this study, we use genetic variants in ADH/ALDH as proxies for fetal alcohol exposure and investigate their association with offspring ADHD risk, and separately with hyperactive‐impulsive and inattention symptom domains, using data from three large European birth cohorts: the Avon Longitudinal Study of Parents and Children (ALSPAC), Generation R (GenR) and the Norwegian Mother, Father and Child Cohort Study (MoBa). This evidence concerns the gene LDHA and attention deficit-hyperactivity disorder.