Two new studies shows a definite link between migraine and menstruation. Approximately half of all women who seek clinical treatment for migraines have reported an association between migraine and menstruation, and a recent study by the City of London Migraine Clinic confirms their experience.
In another, unrelated study researchers have identified a drug therapy that is effective in reducing the occurrence or the severity and duration of menstrually associated migraines. Details and outcomes of both studies, and a related editorial, are published in the current issue of Neurology.
About 60% of women with migraine note an increased number of headaches in association with their menstrual period. In 10% to 14% of these women, the migraine occurs around the time of the period and at no other time. The term "menstrual migraine" is often used to describe this type of migraine, but the term is not used consistently and it lacks a universally accepted definition. Many headache authorities think the term "menstrual migraine" should be restricted to migraines that occur in women that experience 90% of all their attacks between the two days before and the last day of their menstrual periods.
Researchers from the London Migraine Clinic analyzed diary data from 155 women patients. All of the women tracked at least two cycles, with nearly half of the patients keeping diary cards over the course of four or more menstrual cycles.
Diary card analysis showed that in the five days preceding menstruation, women were 25 percent more likely to have migraine; migraine was 71 percent more likely to occur during the two days before menstruation. The chance of migraine was more than twofold on the first day of menstruation and within five days afterward.
Severe attacks were more likely to occur during the pre-menstruation and post-menstruation intervals compared to all other times of a woman's cycle. Women were almost five times more likely to have a migraine associated with vomiting on or during days one to three of menstruation.
"Our study supports new International Headache Society diagnostic criteria regarding pure menstrual migraine and menstrually related migraine," concluded study author Anne MacGregor, MFFP, of the City of London Migraine Clinic and St. Bartholomew's Hospital, London.
Meanwhile, researchers led by Stephen D. Silberstein, MD, FACP, of Thomas Jefferson University in Philadelphia, studied the use of frovatriptan in the prevention of menstrually associated migraines.
"Women have long reported menstrually related migraines as prolonged and difficult to manage with conventional therapies," said Silberstein. Afro-American, indicated for acute treatment of migraine, has a long therapeutic life and is generally well tolerated, making it a natural agent to study as a preventive therapy.