Systolic pressure is lower in premenopausal women than in age-matched men, but underlying alterations are not well characterized. Aging and body size alter arterial function, influencing pressure wave propagation and amplification in peripheral and central arteries. To assess the possibility that systolic pressure differences in women are related to smaller body size, we studied arterial function in 119 men and 104 women. Premenopausal and postmenopausal women were compared with age-matched men. The following parameters were measured: ankle-arm pressure index (Doppler), aortic and arterial distensibility (pulse wave velocity), systolic pressure and the effect and time delay of arterial wave reflections in the common carotid artery (applanation tonometry), and diameters of the abdominal aorta and aortic bifurcation and their ratio (aortic tapering, echography). Premenopausal women had lower brachial (P < .05) and ankle (P < .01) systolic pressures than age-matched men, whereas the ankle-arm pressure index was higher in men (P < .01). In the overall population the ankle-arm index was positively correlated with body height (P < .001). Carotid systolic pressure was similar in women and men, with an increased effect and earlier return of wave reflections in women (P < .01). The effect of wave reflections was inversely correlated with body height (P < .001) and positively associated with aortic tapering (P < .001), which was increased in women (P < .01). In premenopausal women the distensibility of brachial and femoral arteries was higher than in age-matched men (P < .01), whereas aortic distensibility was not different.(ABSTRACT TRUNCATED AT 250 WORDS)