Hu J, Lin JH, Jiménez MC, et al. - Given an association of exogenous hormone therapy (HT) use with increased risk of ischemic stroke in postmenopausal women, researchers here examined correlations between plasma sex hormone levels and ischemic stroke risk, by HT status. They performed a nested case-control study of postmenopausal women from the NHS (Nurses’ Health Study) including women with confirmed incident ischemic stroke (n = 419) and matched controls (n = 419) by age, HT use, and other factors. Current HT users differed from never/past users in terms of their hormone profiles. Neither current users nor never/past users exhibited any clear linear trends between estradiol (total or free) levels or the estradiol/testosterone ratio and ischemic stroke risk. Findings thereby suggest that in postmenopausal women, there is no role of sex hormone levels in mediating ischemic stroke risk. Among women with a body mass index < 25 kg/m², current users exhibited an association of a higher estradiol/testosterone ratio with significantly raised ischemic stroke risk, and never/past users showed a significant association of higher levels of total and free estradiol with higher ischemic stroke risk.