Aims: We sought to determine whether fasting or post-challenge glucose were associated with progression of coronary atherosclerosis in non-diabetic women. Methods: We performed a post-hoc analysis of 132 non-diabetic women who underwent 75-g oral glucose tolerance testing. The primary outcome of interest was progression of atherosclerosis determined by baseline and follow-up coronary angiography, a mean of 3.1 ± 0.9 years apart. We analysed the association of change in minimal vessel diameter (ΔMD) by quartile of fasting and post-challenge glucose using mixed models that included adjustment for age, systolic blood pressure, total : high-density lipoprotein cholesterol ratio, current smoking, lipid-lowering and anti-hypertensive medication use and other covariates. Results: At baseline, participants had a mean age of 65.7 ± 6.7 years and a mean body mass index of 27.9 ± 8.5 kg/m 2. Although there were no significant differences in atherosclerotic progression by fasting glucose category (P for trend across quartiles = 0.99), there was a significant inverse association between post-challenge glucose and ΔMD (in mm) (Q1 : 0.01 ± 0.03; Q2 : 0.08 ± 0.03; Q3 : 0.13 ± 0.03; Q4 : 0.11 ± 0.03; P for trend = 0.02). Conclusions: In post-menopausal women without diabetes, post-challenge glucose predicts angiographic disease progression. These findings suggest that even modest post-challenge hyperglycaemia influences the pathogenesis of atherosclerotic progression. © 2007 The Authors.