More importantly, this guideline may empower women and their families to under- stand their own risk and how they can minimize the chances of having a stroke. Epidemiology of Ischemic and Hemorrhagic Stroke in Women Overview In the United States, more than half (53.5%) of the esti- mated 795 000 new or recurrent strokes occur among women annually, resulting in 55 000 more stroke events in women than men.1 Results from the Framingham cohort show that women have a higher lifetime risk of stroke than Although stroke incidence rates have declined, data suggest that the decline may be smaller for women than Data from epidemiological studies demonstrate that the majority (87%) of strokes are ischemic (IS), with the remainder hemorrhagic (10% intracerebral [ICH] and With an anticipated increase in the aging population, the prevalence of stroke survivors is projected to increase, particularly among elderly women.4 Because the United States lacks a national surveillance sys- tem for cardiovascular disease (CVD),25 and sex-specific or age- and sex-specific stroke incidence data have not been routinely reported in published studies, there are important gaps in our understanding of sex differences in incident and recurrent stroke events, temporal patterns of stroke events, and outcomes after stroke. Most of what is known about the epidemiology of stroke comes from mortality data. As noted previously, the higher stroke mortality for women is often attributed to the longer life expectancy of women. Of occurred in women.1 Bushnell et al Guidelines for Prevention of Stroke in Women 1547 Incidence Ischemic Stroke Within most age strata, women have a lower IS incidence than men, and as such, the overall age-adjusted incidence of IS is lower for women than men4,24,26 31 ; however, sex differences in IS incidence rates differ across the age strata. 