About 18 million American women get migraines. But it's the 20% of migraines that come with aura—the visual disturbances that warn of impending headaches—that seem to be associated with an increased stroke risk. One recent study found that among women who get migraines with aura, those who smoke and take oral contraceptives have seven times the risk for stroke. That lethal combination is what's thought to have contributed to Kim's stroke. She's since given up cigarettes and gone off the pill—smart moves for any woman who gets migraines, even those without aura (since one French study found that suffering from migraines without aura can still triple stroke risk).