Race, oxygen exposure, and retinopathy of prematurity: re-examining a persistent epidemiologic paradox

Retinopathy of prematurity (ROP) is a leading cause of childhood blindness that arises from disrupted retinal vascular development in premature infants. Oxygen exposure remains a central driver of treatment-warranted ROP, as higher saturation levels suppress early retinal vascular growth and later promote pathological neovascularization. Large, randomized trials of oxygen targeting show that lower oxygen saturation ranges reduce the incidence of treatment-requiring ROP, though with trade-offs in mortality. Observational cohorts, including the CRYO-ROP, ETROP, and e-ROP trials, consistently report lower rates of treatment-warranted ROP and reduced treatment need among Black infants despite similar or greater prematurity risk. Multiple explanations have been proposed to account for the paradoxically lower rates of treatment-warranted ROP observed among Black infants. Although biologic variations in angiogenic pathways have been proposed, evidence suggests that structural and clinical factors may offer an alternative explanation for these patterns. Black race is strongly correlated with residence in neighborhoods with greater socioeconomic disadvantage, which is associated with increased risk of prematurity and missed ROP follow-up visits. In addition, pulse oximeters may overestimate oxygen saturation in individuals with darker skin pigmentation, potentially altering targeted oxygen exposure. Survival-related selection bias may further contribute to this paradox, as infants at the highest risk of both mortality and treatment-warranted ROP may not survive long enough to develop treatment-requiring disease. This review examines racial differences in ROP severity and examines how oxygen exposure and structural factors may contribute to these disparities, while acknowledging the limited evidence supporting biologic explanations.