At what age does retinopathy of prematurity (ROP) typically stop being a concern?

When ROP Stops Being a Concern

ROP screening can be safely discontinued when the infant reaches 45 weeks postmenstrual age without developing prethreshold ROP or worse, when retinal vessels progress into Zone 3 without prior Zone 2 disease, or when complete retinal vascularization occurs. 1, 2

Age-Based Discontinuation Criteria

Postmenstrual Age Threshold:

• Screening can stop at 45 weeks postmenstrual age if the infant has not developed prethreshold ROP or worse. 2 This represents the primary age-based cutoff where the risk of vision-threatening ROP has essentially passed.

Gestational Age Considerations:

• Infants born at greater than 32 weeks gestational age do not develop type 1 ROP and never require screening in the first place. 3
• No infant with gestational age >32 weeks at birth developed type 1 ROP in a large cohort of over 11,000 infants. 3

Anatomic Criteria for Discontinuation

Zone-Based Progression:

• ROP that is regressing with vessels passed into Zone 3 on at least two sequential examinations is extremely unlikely to progress to threshold ROP. 4, 1, 5 This is one of the safest indicators that screening can cease.
• Infants whose vessels remain in Zone 1 or Zone 2 are at higher risk and require continued monitoring every 1-2 weeks. 4, 1

Complete Vascularization:

• Full retinal vascularization indicates screening can be discontinued, as the developmental window for ROP has closed. 1, 2

Timing of Peak Risk

When ROP Develops:

• Type 1 ROP is first diagnosed at a median postmenstrual age of 36 weeks (range 30-46 weeks). 3
• The mean postnatal age at diagnosis remains relatively consistent at 11-13 weeks across different gestational ages. 3
• In 99% of infants, retinal conditions indicating risk of poor outcome are not observed before 31 weeks postmenstrual age or 4 weeks chronologic age. 2

Critical Pitfalls in Discontinuing Surveillance

Home Discharge Concerns:

• The greatest risk occurs when infants with unresolved ROP in Zone 1 or 2 are discharged home and miss follow-up appointments. 4 This represents a tragedy where successful NICU graduation leads to preventable blindness.
• Parents cannot typically provide close oxygen control at home without extensive support, which may worsen ROP progression. 4

Oxygen Management:

• Once past the age of oxygen-induced retinopathy risk (typically after vessels reach Zone 3), target oxygen saturation of 95% or higher is recommended. 4, 5
• The STOP-ROP trial found that saturation targets of 96-99% do not increase risk of ROP progression in infants with pre-threshold disease. 4

Practical Algorithm

1. Continue screening if:

   • Infant is <45 weeks postmenstrual age AND has any ROP in Zone 1 or 2
   • Any prethreshold or threshold ROP is present regardless of age

2. Discontinue screening when ANY of these occur:

   • 45 weeks postmenstrual age reached without prethreshold ROP 2
   • Vessels progress into Zone 3 on two consecutive exams without prior Zone 2 disease 4, 2
   • Complete retinal vascularization documented 1, 2

3. Never screen:

   • Infants born >32 weeks gestational age 3
   • Infants 29-37 weeks with medically stable course (though conservative approach screens all <32 weeks) 1