The development of neonatology and neonatal care has significantly improved the survival rate of preterm infants, but the improvement in the incidence of bronchopulmonary dysplasia is still limited.

Bronchopulmonary dysplasia (BPD) is defined as a chronic lung disease that occurs when an infant requires oxygen support for at least 28 days after birth, with severity depending on the degree of oxygen dependence and mechanical ventilation support to maintain SpO2 above 89%.