Roughly 60% of menstruating people with migraine experience attacks linked to their cycle. The danger window is a five-day stretch: 2 days before menses begins through day 3 of bleeding. The trigger is not menstruation itself but the steep estrogen drop that precedes it. Menstrual migraines are often longer, more severe, more nausea-heavy, and more resistant to standard triptans than non-menstrual attacks. They can be predicted, prevented, and treated, but only if you know the calendar.
The hormonal migraine cycle is one of the most predictable patterns in all of neurology. Hormones do not cause migraine, but their fluctuation triggers it in a brain that is already predisposed. If you are charting a typical 28-day cycle, here is what happens.
Days 1 to 5: the high-risk window (menses)
Day 1 is the first day of bleeding. Estrogen and progesterone are at their lowest point of the entire cycle, having dropped sharply over the previous 48 hours. This is the trigger.
Attack risk in this window:
- Pure menstrual migraine (PMM): attacks occur ONLY in days minus-2 to plus-3 around menses
- Menstrually-related migraine (MRM): attacks occur in this window AND at other times of the cycle
About 7 to 14% of people who menstruate have pure menstrual migraine. Up to 60% have menstrually-related migraine. The clinical distinction matters because PMM responds well to short-burst prevention timed to the cycle, while MRM needs both timed and ongoing strategies.
For deeper coverage, see menstrual migraine management.
To check your own timing, use the free Menstrual Migraine Pattern Calendar. It compares attack starts across three cycles with the recognized menstrual window and provides a non-diagnostic timing summary.
Days 6 to 13: the calm window (follicular phase)
Estrogen rises steadily. This is the lowest-risk part of the cycle for most people. If you keep a migraine diary, you will see attack frequency drop sharply here.
Use this window to:
- Plan high-stakes meetings, travel, and exercise
- Refill prescriptions and schedule appointments
- Catch up on sleep debt from the previous attack
Day 14: ovulation (small secondary peak)
Estrogen surges before ovulation, then drops briefly. A subset of people experience a mid-cycle attack tied to this drop. It is usually milder than the menstrual window but worth noting.
Days 15 to 24: the luteal-phase calm
Estrogen and progesterone are both elevated and relatively stable. Most people have very few attacks here.
Days 25 to 28: the danger window begins
Estrogen falls sharply in the final 3 to 5 days of the cycle. This is where prodromal symptoms cluster: food cravings, irritability, fluid retention, mood changes. For people with hormonal migraine, this is when you start preventive treatment, not when the attack begins.
Why estrogen withdrawal triggers migraine
Estrogen modulates serotonin, CGRP, and cortical excitability. When estrogen drops:
- Serotonin levels fall, reducing the brain's pain-dampening capacity
- CGRP release increases in the trigeminovascular system
- The cortex becomes more excitable, lowering the threshold for cortical spreading depression
- Inflammation in the meninges rises
This is why simply taking estrogen at the right time can prevent attacks. See hormonal migraine and estrogen and estrogen ache equation.
How to treat the calendar
Short-burst prevention (mini-prophylaxis)
Start 2 days before expected menses, continue through day 3 of bleeding (5 to 7 days total):
- Naratriptan 1 mg twice daily
- Frovatriptan 2.5 mg twice on day one, then 2.5 mg daily
- Naproxen 550 mg twice daily
- Magnesium 400 to 600 mg daily through the window
Hormonal stabilization
For people on combined hormonal contraception, eliminating the placebo week (continuous dosing) removes the estrogen-withdrawal trigger entirely. Some neurologists use a low-dose estradiol patch in the high-risk window to prevent the drop.
Caution: combined hormonal contraception is not safe for people with migraine with aura due to elevated stroke risk. Talk to your neurologist before starting.
Acute treatment
Menstrual attacks often need a longer-half-life triptan (eletriptan or frovatriptan) plus an NSAID and an antiemetic. Standard sumatriptan can fail because the attack outlasts the drug.
Track to predict
Track at least three cycles to assess whether the timing repeats in two out of three. Note bleeding start day, attack start day, and attack severity. Voice logging during the prodrome is the most useful single data input. See identifying hidden migraine patterns and perimenopause migraine changes for what happens when this calendar starts breaking.
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