Which of the following best describes the risk factors for ROP related to oxygen in the first weeks of life?

• A. Oxygen level fluctuations and frequent intermittent hypoxia
• B. Stable oxygen levels
• C. Consistently high oxygen saturation
• D. No relationship between oxygen and ROP

Answer: (A)

In premature infants, the level of oxygen the retina experiences in the early weeks drives the development of abnormal blood vessels. When oxygen levels swing up and down, the retina undergoes cycles of hyperoxia followed by hypoxia. Hyperoxia suppresses normal vessel growth, and when oxygen falls, it triggers a surge of factors like VEGF that push for new, but disorganized, blood vessels. This erratic vascular growth is what leads to retinopathy of prematurity.

That’s why describing the risk as fluctuations in oxygen with frequent intermittent hypoxia best captures the dangerous pattern: the repeated transitions between high and low oxygen create the conditions for abnormal neovascularization. Stable or consistently high oxygen levels are less predictive of this specific mechanism, and there is a clear relationship between oxygen and ROP, so saying there’s no relationship isn’t accurate.