Estrogens, migraine, and stroke.

Epidemiological studies suggest the existence of close but complex relationships between estrogens, migraine, and stroke in women before menopause. Migraine, particularly without aura, is strongly influenced by estrogens as illustrated by the frequency of onset at puberty, of menstrual migraine, and of improvement during pregnancy. Migraine, particularly with aura, is a risk factor for ischemic stroke with a relative risk of 3, further increased by tobacco smoking and oral contraceptive use. The pathophysiological mechanism underlying these close relationships remains unknown. In practice, given the very low absolute risk of stroke in young women, there is no systematic contraindication to oral contraceptive use in young female migraineurs but rather a firm recommendation for no smoking and for the use of low-estrogen-content pills or progestogens only, particularly in migraine with aura.