Oral health knowledge, preventive practices, and Health Belief Model constructs among pregnant women in Iran: a cross-sectional study

Physiological and hormonal changes during pregnancy increase susceptibility to oral diseases. Maternal oral health practices may influence maternal and child health outcomes. This study aimed to assess oral health knowledge, preventive practices, and health beliefs as conceptualized by the Health Belief Model among pregnant women in Iran. This cross-sectional study included 350 pregnant women attending comprehensive health service centers in Karaj, Iran, in 2025. Participants were selected using a stratified sampling method. Data were collected using a validated HBM-based questionnaire (Cronbach’s alpha = 0.84). Associations between study variables were examined using chi-square, Fisher’s exact test, and multiple linear regression in SPSS version 27. A significance level of 0.05 was applied. The mean oral health knowledge score was 46.99 ± 13.19, indicating low knowledge. However, 82.9% ( n = 290) of participants brushed before bedtime, whereas only 31.4% ( n = 110) brushed after consuming sugary foods. Overall, 50.9% ( n = 178) had visited a dentist before pregnancy. Dental fear was the most frequently reported perceived barrier. Maternal university education was independently associated with higher knowledge scores (B = 5.53, 95% CI: 0.44–10.62, p = 0.03). Higher overall HBM scores were independently associated with marriage duration ˃10 years (B = 2.37, 95% CI: 0.48–4.27, p = 0.014), spouse’s university education (B = 4.53, 95% CI: 2.08–6.98, p < 0.001) and health insurance (B = 2.45, 95% CI: 0.88–4.02, p = 0.002). Second pregnancy trimester (B= -2.27, 95% CI: -4.50 − -0.05, p = 0.045), good household income (B= -3.13, 95% CI: -5.39 − -0.87, p = 0.007), and spouse’s occupation (B= -2.56, 95% CI: -5.07 − -0.06, p = 0.045) were associated with lower HBM scores. Despite a low mean of oral health knowledge, preventive practices remained suboptimal, highlighting important gaps in both oral health knowledge and preventive care behaviors. Maternal education associated with oral health knowledge, whereas health beliefs were associated with several sociodemographic and obstetric factors, with dental fear emerging as a major barrier to dental care. These findings may inform the development of HBM-based oral health interventions into routine prenatal care to reduce barriers and promote preventive oral health practices.