It is unclear why blood pressure (BP), metabolic markers and smoking increase stroke incidence in women more than men. We examined these associations with carotid artery structure and function in a prospective cohort study.Participants in the Australian Childhood Determinants of Adult Health study at ages 26-36 years (2004-06) were followed-up at 39-49 years (2014-19). Baseline risk factors included smoking, fasting glucose, insulin, systolic and diastolic BP. Carotid artery plaques, intima-media thickness [IMT], lumen diameter and carotid distensibility [CD] were assessed at follow up. Log binomial and linear regression with risk factor × sex interactions predicted carotid measures. Sex-stratified models adjusting for confounders were fitted when significant interactions were identified.Among 779 participants (50% women), there were significant risk factor × sex interactions with baseline smoking, systolic BP and glucose associated with carotid measures in women only. Current smoking was associated with incidence of plaques (RR 1.97 95% CI 1.4, 3.39), which reduced when adjusted for sociodemographics, depression, and diet (RR 1.82 95% CI 0.90, 3.66). Greater systolic BP was associated with lower CD adjusted for sociodemographics (β -0.166 95% CI -0.233, -0.098) and hypertension with greater lumen diameter (β 0.131 95% CI 0.037, 0.225), which decreased when adjusted for sociodemographics, body composition and insulin (β 0.063 95% CI -0.052, 0.178). Greater glucose (β -0.212 95% CI -0.397, -0.028) was associated with lower CD, which decreased when adjusted for sociodemographics, BP, depression and polycystic ovary syndrome (β -0.023 95% CI -0.249, 0.201).unadjustedSmoking, SBP and glucose affect carotid structure and function more in women than men with some of this risk due to co-occurring risk factors.