Leroy S, et al. - This study was designed in order to accurately delineate the timing and contribution of inflammation to bronchopulmonary dysplasia (BPD) in preterm infants, during the neonatal period. The occurrence of systemic inflammation was reported early in the neonatal period. It was found to precede clinical symptoms in infants with BPD. Hence, a discrete vulnerability window period was yielded which supported a role for targeted intensive care interventions during the early phase of BPD.