ROP occurs primarily in premature infants.

It is estimated that ROP occurs in over 15-20 % of all premature births and the incidence correlates with the birth weight, reaching approximately 50-70 % in infants whose weight is less than 1250 g at birth.

In addition to prematurity, other risk factors include: infants born under 32 weeks gestation, weight less than 1500 g, apnea, mechanical ventilation, high levels of supplemental oxygen, high carbon dioxide levels, seizures, anemia, bradycardia.
ROP is prevalent worldwide and seems to affect equally male and female infants. Some reports, however, indicate a slight male predilection. Increased severity of the disease has also been reported in male infants. Reduced risk of severe ROP in black infants compared to Caucasian and Asian infants have been reported.
ROP was the leading cause of blindness in children in the 1940s and 1950s. Today, there is an increase in ROP due to the neonatal care advances and the rising number of surviving premature babies.