Classification of perimenstrual headache: clinical relevance.

Although more than 50% of women with migraine report an association between migraine and menstruation, menstruation has generally considered to be no more than one of a variety of different migraine triggers. In 2004, the second edition of the International Classification of Headache Disorders introduced specific diagnostic criteria for menstrual migraine. Results from research undertaken subsequently lend support to the clinical impression that menstrual migraine should be seen as a distinct clinical entity. This paper reviews the recent research and provides specific recommendations for consideration in future editions of the classification.