The purpose of this study was to determine the prevalence and risk factors associated with self-reported vaginal discharge among pregnant women in the city of Rio Grande, South Brazil. Using a cross-sectional design, a standard interview was applied to pregnant women at home by previously trained interviewers, covering the following: demographic, reproductive, and socioeconomic data, household conditions, health care, and illnesses during pregnancy, including vaginal discharge. The chi-square test was used to compare proportions, and Poisson regression was used in the multivariate analysis. Among the 339 pregnant women interviewed, 52% reported vaginal discharge. The following variables were significantly associated with the outcome: age (prevalence rate, PR = 1.49), marital status (PR = 1.31), urinary tract infection (PR = 1.56), hyperglycemia (PR = 1.48), use of an intrauterine device (PR = 2.35), and history of preterm delivery (PR = 1.37), with oral contraception showing a protective effect (PR = 0.79). Prevalence of self-reported discharge was high among this group of pregnant women. Several risk factors were also identified for the disease under study. These findings can contribute to the implementation of preventive interventions.