BackgroundEarly childhood caries (ECC) is the most common dental disease among children, which can affect children’s primary teeth during their teething. This study evaluates an intervention for preventing early childhood caries in a pediatric population in Ahvaz, Iran.MethodThe population of this study (IRCT2017070210804N10) consists of 104 women with 12 to 36 months of age without dental caries referred to a health care center in Ahvaz, Iran. The children were randomly assigned to either an experimental or control group in equal numbers. First, the demographic information of participants was collected through a questionnaire containing components of perceived threat, health literacy, and oral health behaviors using a valid and reliable questionnaire. The ECC status of the children was established by a dentist. Control group received “standard well baby care”. The experimental group received standard well baby care in addition to educational interventions, including lecture and group discussion. After 6 months, the participant completed the questionnaire for the second time, and the children’s teeth were reexamined. Data were analyzed using SPSS version 15 at a significance level of p < 0.05.ResultsThe mean ages of women and children were 31 ± 6.68 years and 18 ± 7.21 months, respectively. Before the intervention, no significant difference was documented between the groups for the study variables, p > 0.05. However, after the intervention, a significant difference was observed between the perceived threats (41.15 ± 4.46 in the experimental group and 38.26 ± 4.21 in the control group, p = 0.001), health literacy (20.98 ± 2.15 in the experimental group and 19.76 ± 2.70 in the control group, p = 0.01), oral health behaviors (7.75 ± 2.30 in the experimental group and 6.15 ± 2.65 in the control group, p = 0.01), and the incidence of ECC (13% in the experimental group and 35% in the control group,p = 0.001).ConclusionThis intervention had positive effects on the perceived threat, health literacy, and health behaviors; and the intervention could reduce the incidence of ECC. The finding of this study provided a suggestion for evidence-based decision-making processes regarding ECCs prevention programs.Trial registrationIRCT2017070210804N10 (retrospectively registered)