According to a study, estrogen and other sex hormones could be responsible for the higher prevalence of migraine in women. The research suggests that sex hormones affect cells around the trigeminal nerve and connected blood vessels in the head, with estrogens -- at their highest levels in women of reproductive age -- being particularly important for sensitising these cells to migraine triggers. Some hormones need much more research to determine their role. However, estrogen stands out as a key candidate for understanding migraine occurrence. It was first identified as a factor by the greater prevalence of migraine in menstruating women and the association of some types of migraine with period-related changes in hormone levels. The research team's evidence now suggests that estrogen and changes in estrogen levels sensitise cells around the trigeminal nerve to stimuli. That makes it easier to trigger a migraine attack.