The role of men’s self-efficacy and women’s reports in predicting biochemical exposure to secondhand smoke during pregnancy: a cross-sectional study

Exposure to secondhand smoke (SHS) during pregnancy poses serious health risks. This study investigated the relationships between smoking men’s self-efficacy, their cigarette consumption, their pregnant spouses’ reported exposure, and salivary cotinine levels as an objective biomarker of SHS exposure. This cross-sectional study included 140 smoking men and their pregnant wives in Isfahan, Iran. Mean (SD) men’s self-efficacy was 37.86 (4.27), cigarette consumption was 6.46 (4.50) cigarettes/day, reported exposure was 1.83 (1.82) cigarettes/day, and salivary cotinine was 52.90 (33.39) pg/ml. Significant correlations were observed between self-efficacy and cigarette consumption ( r = −0.31), self-efficacy and reported exposure ( r = −0.41), self-efficacy and cotinine ( r = −0.27), and between reported exposure and cotinine ( r = 0.72). In the adjusted regression model, women’s reported exposure (β = 0.63, p < 0.001) and men’s self-efficacy (β = −0.14, p = 0.022) independently explained 56% of the variance in salivary cotinine. Men with higher education and non-manual occupations exhibited significantly higher self-efficacy and lower exposure outcomes. Higher men’s self-efficacy was associated with lower cigarette consumption and lower spousal exposure. Women’s reports were the strongest predictor of cotinine, with men’s self-efficacy providing an independent additive contribution.