When should retinopathy of prematurity (ROP) screening occur for preterm infants, and what risk factors increase the likelihood of developing ROP?

• A. Screening begins at 4-6 weeks chronological age or around 31 weeks gestational age, whichever is later; risk factors extreme prematurity and prolonged supplemental oxygen.
• B. Screening should be done at birth; risk factors include term birth.
• C. Screening begins after 6 months.
• D. Screening is not indicated in preterm infants.

Answer: (A)

ROP screening is timed to catch developing disease before it can progress to sight-threatening stages, during the period when retinal vessels are still maturing. The recommended start is around 31 weeks gestational age or 4 weeks after birth, whichever occurs later, with follow-up exams as directed by the ophthalmologist. This window ensures the most at-risk infants—those with very immature retinal vasculature—are evaluated before abnormal vessels can cause irreversible damage.

The two most important risk factors are extreme prematurity and prolonged or high-concentration supplemental oxygen. Very early birth means the retina is still immature, making abnormal neovascularization more likely. Oxygen exposure, especially if it’s prolonged or fluctuating, disrupts normal vessel growth and promotes abnormal retinal vessels. Other factors like sepsis or intraventricular hemorrhage can increase risk, but the combination of very early birth and significant oxygen exposure is the strongest predictor for needing screening and potential treatment.