IMPORTANCE: Prophylactic vitamin A supplementation has been shown to reduce the incidence of chronic lung disease or death in extremely low-birth-weight infants. Beginning in 2010, a national shortage reduced the supply of vitamin A available. OBJECTIVE: To estimate the association between vitamin A supplementation and death or chronic lung disease in the context of the recent drug shortage. Intercenter variability in vitamin A use was assessed secondarily. DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort study of 7925 infants with birth weights between 401 and 1000 g who were cared for in US neonatal intensive care units managed by the Pediatrix Medical Group. Infants were discharged between January 1, 2010, and June 30, 2012, and data were collected from the Pediatrix Clinical Data Warehouse. Infants who had major congenital anomalies, died during the first 3 days of life, or had missing data were excluded from the analysis. EXPOSURES: Vitamin A supplementation. MAIN OUTCOMES AND MEASURES: The primary outcome was either death before hospital discharge or chronic lung disease, defined as receiving any respiratory support at 36 weeks' corrected gestational age. RESULTS: Of the 6210 eligible infants, 3011 (48.5%) experienced the primary outcome. Those who received vitamin A were more immature and more likely to receive mechanical ventilation during the first 3 days of life. During the study period, vitamin A supplementation significantly decreased (27.2% to 2.1%); however, the primary outcome was similar (48.4% to 49.5%; P = .40). Vitamin A was unrelated to death or chronic lung disease in unadjusted or multivariable analyses (relative risk [RR], 0.97; 95% CI, 0.91-1.03; P = .32) when demographic and clinical information were considered. After classifying centers by vitamin A use, the center of birth was significantly associated with the outcome, with birth in low- and medium-use centers related to a reduced likelihood of death or chronic lung disease. CONCLUSIONS AND RELEVANCE: The occurrence of death or chronic lung disease appears unaffected by the recent shortage of vitamin A. However, the center of birth appears to be an important risk factor for these infants' outcomes.