In addition, duration of use did not change the risk estimates.144 Although this study followed a very large number of women, it is limited because risk factors and stroke cases were based Bushnell et al Guidelines for Prevention of Stroke in Women 1559 on administrative data. The authors concluded that the RR of IS with intermediate-dose ethinyl estradiol and different pro- gestin types was lower than that reported in other studies and that the transdermal and vaginal ring routes of contraception conferred a similar risk as pills.144 Hemorrhagic Stroke Risk Data regarding risk with OC use have been less consistent for hemorrhagic stroke. The World Health Organization reported an overall slightly increased risk of hemorrhagic stroke (both intracerebral and subarachnoid) with OC use; however, this risk was present in developing countries but not in Europe.220 Also, European women >35 years of age were at increased risk of SAH, whereas women in developing nations were at increased risk of both ICH and SAH. Women with hyperten- sion and who smoked cigarettes were also at increased risk.221 In the Swedish Women s Lifestyle and Health Cohort, there was a significant decrease in hemorrhagic stroke among women who were parous (versus nulliparous; HR, 0.5; 95% CI, 0.2 0.8) and a nonsignificant increase in women who started OC use after 30 years of age (HR, 2.3; 95% CI, 0.8 6.8) and stopped using OCs based on doctor recommendation for medical reasons (adjusted HR, 2.1; 95% CI, 0.9 5.0).219 Hemorrhagic stroke in young women is relevant in Asia, where the risk of this type of stroke is disproportionately higher than in Europe and North America. 