Brain Behav. 2026 Jun;16(6):e71330. doi: 10.1002/brb3.71330.
ABSTRACT
BACKGROUND: Thirdhand smoke (THS) is a persistent environmental toxin that poses significant health risks, especially to vulnerable populations such as pregnant women and their fetuses. Effective interventions to enhance knowledge, modify beliefs, and improve protective practices are crucial. This study aimed to evaluate the impact of a structured, multi-component educational intervention on knowledge, beliefs, and self-reported practices related to THS among pregnant women.
METHODS: A randomized controlled trial was conducted with 100 pregnant women in their second or third trimester, recruited from comprehensive health centers in Isfahan, Iran. Participants were randomly assigned to an intervention group (n = 50) or a control group (n = 50). The intervention group received a multi-faceted educational program consisting of four face-to-face group sessions, one spousal session, educational pamphlets, and reinforcement messages via a social media group. The control group received routine prenatal care. Data were collected using validated questionnaires assessing knowledge (11 items), beliefs (using the Beliefs About Thirdhand Smoke-BATHS scale, 9 items), and self-reported practices (9 items) at baseline and two months post-intervention. Data were analyzed using paired t-test, Wilcoxon signed-rank test, and Analysis of Covariance (ANCOVA) in SPSS v.23.
RESULTS: The intervention group demonstrated significant improvements in mean scores of knowledge (from 13.30 ± 2.68 to 21.52 ± 5.23, p < 0.001), beliefs (from 25.60 ± 8.12 to 38.46 ± 4.01, p < 0.001), and self-reported practices (from 10.50 ± 1.50 to 13.52 ± 2.10, p < 0.001) after the intervention. No significant changes were observed in the control group. ANCOVA results, while controlling for baseline scores, confirmed a statistically significant effect of the intervention on post-intervention scores for knowledge (F = 179.61, p < 0.001), beliefs (F = 77.52, p < 0.001), and practices (F = 54.14, p < 0.001).
CONCLUSION: A structured, theory-based educational intervention significantly improved knowledge, beliefs, and self-reported protective practices concerning THS among pregnant women. Integrating such comprehensive programs into routine prenatal care is strongly recommended to mitigate THS exposure risks and promote maternal and fetal health.
TRIAL REGISTRATION: This randomized controlled trial was prospectively registered in the Iranian Registry of Clinical Trials (IRCT) on 25/04/2025, prior to participant recruitment (Identifier: IRCT20250105064282N1). https://irct.behdasht.gov.ir/trial/81695.
PMID:42252955 | DOI:10.1002/brb3.71330
