Menstrual migraine describes attacks that occur reliably around day one of your period, give or take two days, in at least two of three cycles. The leading explanation is the sharp fall in oestrogen before menstruation. These attacks tend to be longer, more severe and more treatment-resistant than other migraines.

What counts as menstrual migraine?

The formal definition is attacks occurring between two days before and three days after the start of menstruation, in at least two out of three cycles.

There are two versions. Pure menstrual migraine means attacks happen only in that window. Menstrually-related migraine means attacks happen in that window and at other times too, and this is by far the more common pattern.

Roughly 6% of women of reproductive age are affected. Among women aged 30 to 34, around 5.3% have menstrually-related migraine without aura, while pure menstrual migraine is much rarer at around 0.8%. Note that pattern: menstrual migraine is overwhelmingly the type without aura.

Why does it happen before your period?

The dominant model is oestrogen withdrawal. Oestradiol falls sharply in the late luteal phase, and that drop appears to be the trigger rather than any particular absolute level. Oestrogen influences pain signalling through the trigeminovascular system, the network involved in migraine.

Prostaglandins released from the uterine lining during menstruation are thought to contribute as a second factor, which is part of why cramps and headache often arrive together.

This model is well supported but does not explain every case, and researchers are still working on the rest.

How is a migraine different from an ordinary headache?

Migraine is a neurological disorder, not a bad headache. Typical features include moderate to severe pain, often on one side, often throbbing, made worse by routine physical activity, and accompanied by nausea and/or sensitivity to light and sound. Many people need to lie down in the dark, which is not something a tension headache usually demands.

Menstrual attacks specifically tend to be longer-lasting, more severe, more likely to come back after treatment, and more disabling than the same person's non-menstrual attacks. If you have felt that your period migraines are worse and wondered whether you were imagining it, you were not.

The safety point everyone should know

This is the most important paragraph on this page, so we have not buried it at the bottom.

Migraine with aura and combined hormonal contraception should not be used together. Aura means neurological symptoms before or during a headache: zigzag lines, flashing lights, blind spots, tingling in the face or hand, or difficulty speaking.

Migraine with aura and combined hormonal contraceptives are each independently associated with ischaemic stroke, and together the risks compound. In young women with migraine with aura, ischaemic stroke rates are around 5.9 per 100,000 per year without hormonal contraception, compared with roughly 36.9 per 100,000 per year with it. Current guidance classifies combined hormonal contraceptives as an unacceptable health risk in migraine with aura.

Absolute risk remains low, so this is not cause for alarm. But if you get any aura symptoms and use the combined pill, patch or ring, please tell your doctor. Progestogen-only methods are generally considered safe with any migraine type. Do not stop or change contraception on your own; this is a conversation to have with your doctor.

What does the evidence say about magnesium and riboflavin?

Both come up constantly, so here is the accurate version.

Magnesium holds a Level B rating, meaning "probably effective", from neurology guidelines for migraine prevention. That is the highest grade given to any nutraceutical in this space, so it is not nothing. The trials generally used 400 to 600 mg per day of elemental magnesium. Two caveats: gastrointestinal side effects, particularly loose stools, are common and often dose-limiting; and the trials were in general migraine prevention, with thinner evidence specifically for menstrual migraine.

Riboflavin (vitamin B2) rests largely on one pivotal trial from 1998, in which 400 mg per day for three months produced a 50% or greater reduction in attack frequency in 59% of participants versus 15% on placebo. Later reviews have been less consistent. It appears to reduce frequency more than severity, and typically takes around three months to show any effect. A harmless side effect is bright yellow urine.

Two things to be clear about. Both are preventive approaches studied over months; neither does anything for an attack already underway. And the doses used in these trials are well above typical supplement levels, in some cases above recommended upper limits. We are reporting what was studied, not recommending a dose. Migraine is a diagnosed neurological condition and this belongs in a conversation with your doctor, who can weigh these against the prescription options that also exist.

When to seek urgent medical attention

Some headache features need prompt assessment: a sudden "worst ever" headache, new aura appearing after age 50, aura lasting more than an hour, or headache accompanied by weakness, fever or neck stiffness. Please do not wait these out.

Frequently asked questions

Can I get menstrual migraine if I have never had migraine before?
Migraine can begin at any age, and hormonal changes are a common trigger for a first presentation. Worth seeing a doctor for a proper diagnosis.

Will magnesium stop my migraine attack?
No. It has been studied as a preventive taken daily over months, not as an acute treatment.

Do these headaches improve after menopause?
Many women find migraines settle once cycling hormones stabilise after menopause, though the perimenopausal years can be worse first. Individual patterns vary.

This article is general education, not medical advice. Please speak to a qualified healthcare professional about your own health, headaches and contraception.