Objective Retinopathy of prematurity (ROP) registers enable population-based studies to monitor ROP screening programmes to improve their effectiveness. The aim of this study was to determine the frequency of ROP and the coverage of screening in a South African cohort using a prospective ROP South African (ROPSA) register.

Methods and analysis Infants born from 1 May 2022 to 31 January 2023 and screened prospectively for ROP at five neonatal intensive care units in Cape Town were included. The screening criteria were a gestational age (GA) <32 weeks or birth weight (BW) <1250 g. Data were extracted from the ROPSA register and analysed.

Results 696 of 1154 (60.3%) eligible infants were screened, almost half of whom (45.7%) did not complete screening. ROP was detected in 220 infants (31.6%, 95% CI 28.3% to 35.3%), 7 (1.0%) of whom required treatment. Infants with incomplete screening had a lower mean GA than those who completed screening; 28.7 (SD 1.6, range 25–33) and 29.1 (SD 1.7, range 24–36) weeks, respectively (p=0.004) and a lower mean BW; 1048 (SD 203, range 650–1690) g and 1108.5 (SD 227, range 640–1840) g, respectively (p<0.001).

Conclusions Data from the ROPSA register on the frequency of any ROP and treatment-requiring ROP may be biased due to low screening coverage and high incomplete screening. Reasons need to be explored and corrective interventions initiated. The ROPSA register will enable the impact of these interventions to be monitored. The findings of this study will contribute to the ongoing revision of South African national ROP screening guidelines.