Abstract: Abstract: Objective To investigate the incidence of retinopathy of prematurity (ROP) and analyse the associated risk factors of the severe ROP. Methods A total of 703 preterm infants, who met the ROP screening criteria in Department of Neonatology Maternal and Child Health Hospital of Changzhou and with integrated data from July 2011 to July 2014, were analysed in this study. ROP screening was done by ophthalmologist with binocular indirect ophthalmoscope at 4 weeks after birth or chronological age of 32 weeks. According to the screening results they were decided to be treated or not. Data were collected and compared for the severity of ROP in children with different gestational ages and birth weights. Results The detection rate of mild ROP was 5.26 % and severe ROP was 0.85%. Birth gestational age < 28 weeks and birth weight 500- 1 000 g of the children, the risk of severe ROP was significantly increased. The differences were statistically significant (P < 0.05). Conclusion Gestational age and birth weight are risk factors for severe ROP. Early detection and treatment can prevent the blindness of ROP.

Key words: premature, retinopathy of prematurity, gestational age, birth weight, inhale oxygen