<p><strong>OBJECTIVES: </strong>To compare medical and developmental outcomes over the first 2 years of life in extremely preterm infants with bronchopulmonary dysplasia (BPD) who were discharged on supplemental oxygen via nasal cannula with outcomes of infants with a similar severity of respiratory illness who were discharged breathing in room air.</p>

<p><strong>METHODS: </strong>We performed a propensity score-matched cohort study. Eligible infants were born at &lt;27 weeks' gestation, were receiving supplemental oxygen or respiratory support at 36 weeks' postmenstrual age, and were assessed at 18 to 26 months' corrected age. Study outcomes included growth, resource use, and neurodevelopment between discharge and follow-up. Outcomes were compared by using multivariable models adjusted for center and age at follow-up.</p>

<p><strong>RESULTS: </strong>A total of 1039 infants discharged on supplemental oxygen were propensity score matched 1:1 to infants discharged breathing in room air. Infants on oxygen had a marginal improvement in weight score (adjusted mean difference 0.11; 95% confidence interval [CI] 0.00 to 0.22), with a significantly improved weight-for-length score (adjusted mean difference 0.13; 95% CI 0.06 to 0.20) at 22 to 26 months' corrected age. Infants on oxygen were more likely to be rehospitalized for respiratory illness (adjusted relative risk 1.33; 95% CI 1.16 to 1.53) and more likely to use respiratory medications and equipment. Rates of neurodevelopmental impairment were similar between the groups.</p>

<p><strong>CONCLUSIONS: </strong>In this matched cohort of infants with BPD, postdischarge oxygen was associated with marginally improved growth and increased resource use but no difference in neurodevelopmental outcomes. Ongoing and future trials are critical to assess the efficacy and safety of postdischarge supplemental oxygen for infants with BPD.</p>