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Estrogen Withdrawal: Headache Trigger?

Promising Treatment

Menstrual migraine attacks are not an unknown quantity and doctors have long been aware that there is a connection between the menstrual cycle and migraine headaches. That means that women get more migraines than men. Now, a new study suggests that rising levels of estrogen can act as a preventative against migraine headaches. This opens up new avenues of promising treatment for female migraine headache sufferers.

The hypothesis this study set out to prove is estrogen withdrawal as a migraine trigger. There is a definite relationship between fluctuating estrogen levels during the menstrual cycle and the incidence of migraine. Researchers found that if they timed the doses with care, transdermal, or skin patch estrogen therapy would keep the migraines away.

City of London Migraine Clinic's Dr. Anne MacGregor and her colleagues studied 38 women with menstrual migraine and regular menstrual cycles.  The participants, with a mean age of 43, kept a daily migraine diary and sent in urine samples each morning. It was seen that over the course of three menstrual cycles, migraine incidence was highest on the day before bleeding began in earnest and on the first full day of bleeding. These dates correspond with a drop in estrogen levels. As estrogen levels then began to rise, migraine incidence declined.

MacGregor was not surprised to find proof for estrogen withdrawal as a trigger for migraine, however, she said, "We were surprised to find that rising levels of estrogen appeared to offer some protection."

A second study with the same participants, involved treatment with estrogen supplements around the beginning of the menstrual cycle. There was found to be a reduction in the severity and duration of menstrual migraine attacks.

For six menstrual cycles, women were treated with estrogen gel or a placebo 10 days after ovulation and continued daily treatment through the second full day of bleeding. The result was a 22% reduction in migraine days. Attacks were also less severe with less of a tendency for associated nausea.

The most striking finding was that in the 5 days after treatment with estradiol, a form of estrogen, was discontinued, migraine incidence increased by 40%, as consistent with a delayed estrogen withdrawal.

A Good Strategy

The study suggests that estrogen supplements are effective as long as these are continued for up to several days into the next cycle, avoiding the problem of deferred attacks. The London clinic now recommends this strategy to its patients with menstrual migraine.