Attention-deficit/hyperactivity disorder is associated with altered concentration of neurotrophins, which regulate neuronal growth, morphology, migration, and apoptosis,50,51,52,53 and evidence suggests that neurotrophin expression is regulated by corticosteroids.54,55 Fetal growth restriction did not influence the parent-reported attention-deficit/hyperactivity disorder scale, but repeated betamethasone treatment had a small, positive association with the direct assessment of divided attention and possibly impulse control in children with FGR. This evidence concerns the gene BDNF and attention deficit-hyperactivity disorder.