Women's delay in seeking medical advice for abnormal vaginal discharge can cause serious effects such as infertility, ectopic pregnancy, and advanced cervical cancer. Family healthcare workers are in a unique position to help in the promotion of vaginal health. A nonrandomized controlled trial was conducted among a sample of family healthcare workers in the intervention (n = 37) and a control (n = 37) group to assess the effectiveness of an educational intervention, which was a 2‐day intensive workshop combining reading materials. Data were analyzed using SPSS software (version 20), and the effectiveness of the intervention was determined using a mixed between‐within subjects analysis of variance. The total knowledge and attitude scores were significantly greater for family healthcare workers in the intervention group immediately and at 3 and 6 months after the educational intervention, compared to the control group. A substantial main effect was observed concerning the time, showing an increase in family healthcare workers' knowledge and attitude scores across the four time periods. A statistically significant difference in the median overall health education competency score across the two groups was also observed. The mean score differences in all sub‐competencies in health education were significantly higher among the intervention group, compared to the control group between second postintervention and the baseline. The educational intervention had revealed successful and sustainable improvements in family healthcare workers' knowledge, attitude on vaginal discharge, and health education competency. This can be implemented as an in‐service program for family healthcare workers to improve health education practices.