A favorable benefit-to-risk ratio is well established for a single dose of antenatal corticosteroids in women at risk of preterm delivery. The efficacy is real with an important decrease of mortality and morbidity. No adverse effects were described after one course. Possible beneficial effects of repeated courses include lower rates of RDS and a decrease in oxygen use, whereas an increasing body of evidence raises the concern of multiple short and long term adverse consequences, principally neurological. It seems rational to prescribe one course of corticosteroids. The indication for a second course should be discussed but multiples courses of this treatment should not be prescribed. We prefer betamethasone over dexamethasone because of the better side profile. Further work is needed to understand the long-term effects of this treatment.