Taner A, et al. - Researchers conducted this retrospective analysis to evaluate possible reasons for the increasing incidence of retinopathy of prematurity (ROP) since mid-2015 at the institution. The sample consisted of all preterm infants born July 2013 to June 2017 with gestational age (GA) < 29 completed weeks admitted to the University Hospital Zurich neonatal intensive care unit during the first 28 days of life. GA, days of mechanical ventilation and multiple gestations were significant predictors for severest ROP stage. There was no significant effect on the severest ROP stage of a composite of severe comorbidities. GA has been identified as the only significant risk factor the for severest ROP stage. The increased incidence of ROP at the institution was associated with an increased survival rate of extremely preterm infants. Despite the increase, the incidence compared with other countries is still very low. No other additive factors have been identified.