SUMMARY OBJECTIVE: The aim of this study was to analyze the occurrence and risk factors associated with infections during pregnancy in patients with systemic lupus erythematosus. METHODS: This is a retrospective cohort study using the data of pregnant women who were followed up between 2011 and 2018 at a university hospital. RESULTS: The data of 221 pregnant women with systemic lupus erythematosus were analyzed. The incidence of infections was 22.6% (50/221), with the urinary tract being the most frequent site of infection (32/221, 14.5%) followed by the respiratory tract (15/221, 6.8%). The bivariate analysis showed that active disease, hematological systemic lupus erythematosus, reduced complement, and use of prednisone ≥5 and ≥10 mg increased the chance of infection during early pregnancy (p=0.05, p=0.04, p=0.003, p=0.008, and p=0.02, respectively), while disease activity and anti-DNA positivity increased it at the end of pregnancy (p=0.03 and p=0.04, respectively). Prednisone at a dose ≥5 mg increased the chance of infection in the beginning (p=0.01) and at the end of pregnancy (p=0.008). Multivariate analysis showed that increasing the dose of prednisone from 5 to 10 mg tripled the chance of developing infections in pregnant women with lupus (p=0.02). CONCLUSION: The study showed an increased chance of infections in pregnant women with systemic lupus erythematosus and it was associated with the use of prednisone.