The incidence of coronary heart disease (CHD) is higher in postmenopausal or oophorectomised women than in premenopausal women of the same age. The difference cannot be explicable in terms of conventional CHD risk factors. Since factor VII may be relevant to the pathogenesis of CHD, we have investigated the menopause-related changes in factor VII activation in 228 healthy women aged 45-54 years. A standard factor VII clotting assay (FVIIc) and a factor VII antigen assay (FVIIag) were carried out on the same plasma samples. Both FVIIc and FVIIag levels were significantly higher in postmenopausal than in premenopausal women. Despite the strong correlation between the two assays (r = 0.80), the FVIIc/FVIIag ratio was positively and significantly associated with the menopause, suggesting that activated factor VII form might in part account for the high FVIIc levels in postmenopausal women. With respect to the type of menopause, the highest levels of both FVIIc and FVIIc/FVIIag ratio were found in women having undergone bilateral oophorectomy. These results suggest that raised factor VII coagulant activity may contribute to an increased risk of CHD in postmenopausal women.