Huybrechts KF, et al. - The risk of congenital malformations associated with intrauterine exposure to stimulants was investigated in this study. Findings revealed a small increase in the risk of cardiac malformations associated with intrauterine exposure to methylphenidate but not to amphetamines. When weighing the risks and benefits of alternative treatment strategies for attention-deficit/hyperactivity disorder in women of reproductive age and during early pregnancy, this information was important.