Objective. To study the benefits of antenatal corticosteroids (ACS) in clinical settings and to evaluate the occurrence of long-term neuro-sensory effects such as epilepsy and cerebral palsy (CP). Design. Observational population-based study including all births between gestational weeks 24 and 34 during 1976-1997 in Sweden. Exposure to ACS was evaluated at hospital level. Children were followed up to their ninth birthday. Sample and methods. Seven thousand eight hundred twenty-seven infants of which 5,632 were exposed to ACS. Data on hospital ACS routines was based on questionnaires and interviews with physicians and pharmacy sales. Outcomes were obtained from the national health registers and assessed according to gender of the child. Logistic regression was used to assess associations. Main outcome measures. Neonatal death, low Apgar score, respiratory distress syndrome (RDS), bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), retinopathy of prematurity (ROP), CP, and epilepsy. Results. After adjustment, exposed infants had reduced risks of RDS (OR 0.80, 95% CI 0.70-0.92), late neonatal death (OR 0.86, 95% CI 0.57-1.29), BPD (OR 0.87, 95% CI 0.62-1.22), ROP (OR 0.80, 95% CI 0.48-1.32), IVH (OR 0.93, 95% CI 0.67-1.3), and CP (OR 0.82, 95% CI 0.58-1.15). Males had a higher risk of epilepsy (OR 1.74, 95% CI 0.85-3.55) than females (OR 0.50, 95% CI 0.25-1.03). Conclusion. The results confirm the beneficial effect of ACS regarding RDS in clinical settings. Except for a tendency to increased risk of epilepsy among male infants there were no increased risks of neuro-sensory outcomes.