The following work is centred to investigate VDR polymorphisms (FokI, BsmI, ApaI, TaqI) and their association with risk for neonatal complications such as respiratory distress syndrome, intraventricular hemorrhage, bronchopulmonary dysplasia, necrotizing enterocolitis and retinopathy of prematurity. This evidence concerns the gene VDR and bronchopulmonary dysplasia.