Background Retinopathy of prematurity is the leading worldwide cause of visual impairment. There is little available data on its epidemiology and related factors and consequences in developing countries such as Peru. Due to this lack of information, we decided to do this study. Objectives To evaluate factors related to the development of retinopathy of prematurity in very low birth weight newborn patients. Methods We did a case-control (paired 1:1) study of patients admitted to the Neonatal Intensive Care Unit of the Hospital Cayetano Heredia between 2008 and 2018 who had a complete record in the Neocosur network database (N = 293). The case was defined as a preterm newborn patient with a birth weight lower than 1500 grams who developed any type or stage of retinopathy of prematurity; control was defined as a patient with similar characteristics without retinopathy. Univariate and bivariate analysis (using logistic regression model) was performed to obtain the odds ratio with a 95% confidence interval. Results Data were obtained from 57 cases and 57 controls admitted to the Neonatal Intensive Care Unit at Hospital Cayetano Heredia. Late-onset sepsis was the main factor associated with retinopathy of prematurity (odds ratio 4.39; 95% confidence interval 1.23 to 15.76, p = 0.02). Additionally, we performed a bivariate and multivariate analysis that showed that exposure to supplementary oxygen at 36 weeks of postmenstrual age and retinopathy of prematurity were not significantly associated (8.47; 0.51 to 141.17, p = 0.14). Conclusions Patients with late-onset sepsis have a 4.39 times higher odds of developing retinopathy of prematurity. Prospective studies are needed with larger sample sizes.