Risk factors for retinopathy of prematurity development and progression in the Philippines

To determine the clinico-epidemiologic profile of premature infants diagnosed with retinopathy of prematurity (ROP), and treated for type 1, severe, and aggressive (TOSA) ROP in the different regions of the Philippines.

A multiregional ambispective cohort study of premature infants (<37wk gestational age) referred for ROP screening across 20 hospitals in 12 Philippine regions between January 2024 and September 2025 was conducted. Demographic, neonatal, and maternal risk factors were analyzed. Outcomes were compared between National Capital Region (NCR) and non-NCR cohorts.

Of 2085 referred infants, 1900 premature infants were included. Mean gestational age was 32.34±2.31wk; mean birthweight was 1593±439 g. ROP developed in 483 infants (25%), of whom 177 (37%) progressed to TOSA ROP. Lower gestational age, lower birthweight, male gender, and packed red blood cell transfusion were significantly associated with ROP development, whereas sepsis and oxygen supplementation were not. Among TOSA ROP cases, 87% received treatment, most commonly anti-vasular endothelial growth factor (VEGF) injection (46%) or laser photocoagulation (24%). At the last follow-up, 34% of treated infants had not reached full regression or retinal maturity. ROP incidence was higher in NCR (32%) than in Region Ⅰ and Cordillera Administrative Region (8%, P=0.001), Region Ⅲ (13%, P=0.005), and Region Ⅺ (14%, P=0.001), but lower than Region Ⅵ (55%, P=0.001).

Lower gestational age and birthweight, male, and packed red blood cell transfusion are risk factors of ROP development. This study also provides the first multiregional multicenter data on ROP in the Philippines, demonstrating substantial incidence and progression beyond NCR.