Migraine seems to run in families, very often on the mother's side. Migraine headache is three times more common in women than in men. That increased risk emerges in women when puberty begins and decreases after menopause. Genetics can also hardwire us to get headaches. That we can’t control, but environment also plays a big role. A headache may come after intense exercise at high altitude or with severe dehydration and high temperature. Some of us are just more sensitive to environmental changes, either in the external environment — too much sun, for example — or in our internal environment, from a drop in estrogen levels or a change in sleep pattern. People who are not headache-prone do not usually get headaches under stressful conditions. However, those who are prone to headache often experience headache when under stress or during the letdown period, the time after a stressful period has passed.