Researchers are getting a better understanding of the link between PMS and migraine headaches in women.
A new study finds that for women who get these intense headaches, levels of the hormone oestrogen drop more rapidly in the days before menstruation than in women without the headaches.
"These results suggest that a 'two-hit' process may link oestrogen withdrawal to menstrual migraine," said study author Dr Jelena Pavlovic, of the Albert Einstein College of Medicine/Montefiore Medical Centre in New York City. "More rapid oestrogen decline may make women vulnerable to common triggers for migraine attacks such as stress, lack of sleep, foods and wine."
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Researchers looked at urine samples of 114 women with migraines and 223 women without migraines, average age 47.
Oestrogen levels among those with migraines dropped 40 percent in the days just before menstruation, compared to 30 percent for those without migraines, the study found.
No similar patterns were seen with other types of hormones, according to the study.
More common in women
The results were published online in the journal Neurology.
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"Future studies should focus on the relationship between headaches and daily hormone changes and explore the possible underpinnings of these results," Pavlovic added in a journal news release.
About 12 percent of Americans get migraines, and they're three times more common in women than men, according to the American Migraine Foundation. Besides headaches, migraine attacks can include nausea, vomiting and sensitivity to lights, sound and smells.
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