The association between migraine and menstruation was determined using diary data from 155 women of median age 44 years (range, 15 to 58 years) who were not using hormonal contraception and attended the City of London Migraine Clinic, UK. Within-woman analysis and comparing menstruation days with all other times of 693 cycles showed that migraine was 1.7 times more likely to occur during 2 days before menstruation and 2.1 times more likely to be severe, and 2.5 times more likely to occur in the first 3 days of menstruation when it was 3.4 times more likely to be severe. The chance of migraine attacks was 25% more likely in the 5 days preceding menstruation (relative risk (rr) 1.25) and increased to 71% in the 2 days pre-menstruation (rr 1.71). The risk was highest on the first day of menstruation and the following 2 days (rr 2.50), and the risk of severe migraine with vomiting was 5 times more likely on those days (rr 4.69). 
COMMENT. Migraine at menstruation is different from nonmenstrual migraine and attacks are more frequent and severe, even within individuals.
Headache among adolescent girls in the US was studied at the National Institutes of Health, Bethesda, using a school-based national survey, 1997-98. Headache is a prevalent complaint, occurring in 29.1% of girls in grades 6 through 10, and somatic complaints are frequently associated (stomachache in 20.7%, back pain in 23.6%, and morning fatigue in 30.6%). Heavy alcohol consumption, high caffeine intake, and cigarette smoking daily were strongly linked to the complaints, and parent and teacher support was a deterrent.