The relationship between arterial calcification and serum estradiol levels was studied in 72 postmenopausal female and 59 male subjects. In both sexes, subjects with iliac artery calcification had rather lower serum estradiol levels (8.4 +/- 1.4 pg/ml in the females, and 19.2 +/- 2.5 pg/ml in the males) than controls (16.1 +/- 1.6 pg/ml in the females, and 29.7 +/- 2.4 pg/ml in the males). The bone mineral content of females with iliac artery calcification (0.44 +/- 0.02 g/cm2) was lower than controls (0.52 +/- 0.01 g/cm2); a positive correlation between serum estradiol levels and bone mineral content was found in the females. However, bone mineral content did not significantly differ between males with and without arterial calcification (0.67 +/- 0.03 g/cm2 in the former, and 0.65 +/- 0.02 g/cm2 in the latter). These results indicate that arterial calcification and increased bone resorption are both individual results of estrogen deficiency.