Antenatal maternal anxiety has been shown to be related to infant temperament, childhood disorders, and impulsivity in adolescence. This study prospectively investigated whether antenatal maternal anxiety is associated with performance on a continuous performance task. Sixty-four adolescents (mean age, 15 y; 34 boys, 30 girls) were examined with a computerized continuous performance task (CPT) measuring sustained attention. Results showed that the CPT performance of boys of mothers with high levels of state anxiety during the 12th to 22nd postmenstrual week of pregnancy declined as the task progressed: their processing speed became slower and the variability in their reaction times increased. The study controlled for the possible confounding influences of postnatal maternal anxiety, the parents' educational level, and intelligence. Establishing a link between antenatal maternal anxiety and an objective measure of sustained attention/self-regulation, our results extend the growing evidence for an association between antenatal maternal anxiety and the neurobehavioral development of the offspring up into adolescence.