Oral exogenous estrogen raises C-reactive protein (CRP) concentrations, but the impact of endogenous hormones is unknown. We examined the cross-sectional relation of several serum hormones with CRP, fibrinogen, and white blood cell count - three inflammatory markers linked prospectively to coronary artery disease. Serum hormones were measured on a sample (n = 317) of postmenopausal female participants, with or without carotid intima-media thickening, in the Atherosclerosis Risk in Communities (ARIC) Study. Fibrinogen and white blood cell count were available on all and CRP in a subset (n = 57). Adjusted for age, race, and case-control status, mean CRP was 2-fold greater in the highest vs. lowest quartiles of estrone and androstenedione, and CRP was 2-fold less across quartiles of sex hormone binding globulin. These associations were not all statistically significant with this sample size. Fibrinogen and white blood cell count also were associated positively with estrone, androstenedione, and testosterone (and fibrinogen also with dehydroepiandrosterone sulfate). Adjustment for other risk factors and especially body mass index, a known determinant of endogenous hormone levels, attenuated most associations. In conclusion, several endogenous sex hormones may influence basal levels of inflammatory markers. Obesity appears to play a modulating role.