Migraines are believed to be due to a mixture of environmental and genetic factors. About two-thirds of cases run in families. Changing hormone levels may also play a role, as migraines affect slightly more boys than girls before puberty, but about two to three times more women than men. The risk of migraines usually decreases during pregnancy.
The exact mechanisms of migraine are not known. It is, however, believed to be a neurovascular disorder. The primary theory is related to increased excitability of the cerebral cortex and abnormal control of pain neurons in the trigeminal nucleus of the brainstem.
In the footballers, 22% of headaches conformed to the strict IHS definition of migraine headaches. When the relaxed definition of "footballer's migraine" was used, 34% of headaches met these criteria. Footballers were at significantly increased risk of footballer's migraine than community controls.