Luteal Phase — Estrogen Holds Steady
Mid-luteal estrogen stays elevated and stable, keeping migraine risk low.
- 17%: Migraine prevalence, women (vs ~6% in men)
- Day −2 to +3: Menstrual attack window (relative to bleed onset)
- 1972: Withdrawal theory origin (Somerville's estrogen studies)
- ~14 days: Typical luteal length (post-ovulation to menses)
A stable hormonal plateau
Corpus luteum progesterone and estrogen stay elevated mid-cycle.
Low baseline migraine risk
Steady hormone levels keep trigeminal neurons in a resting state.
Why stability matters
Migraine is triggered by hormonal change, not absolute hormone level.
Somerville showed sudden drops, not low levels, provoke attacks.
Late Luteal Decline Begins
Without fertilization, the corpus luteum regresses and estrogen output falls.
- Day 24–26: Decline onset (of a 28-day cycle)
- ~80%: Total drop magnitude (estrogen and progesterone)
- Falls with estrogen: Serotonin sensitivity (linked pathway)
- Rising: CGRP baseline (calcitonin gene-related peptide)
Corpus luteum regression
Without pregnancy, the corpus luteum stops producing hormones.
Estrogen and progesterone fall together
Both steroid hormones decline in the final luteal days.
Early neural effects
Falling estrogen starts reducing serotonergic and opioid tone.
The steepness of the coming drop, not its size, predicts risk.
Sharp Estrogen Withdrawal
Estrogen collapses within roughly 48 hours just before menses begins.
- ~48 hours: Withdrawal window (before bleeding onset)
- ×2–3: Migraine risk increase (vs mid-cycle baseline)
- Rate-dependent: Critical drop threshold (not absolute level)
- <50 pg/mL: Estradiol at trough (typical premenstrual low)
The withdrawal window
Estrogen falls fastest in the two days before bleeding starts.
Rate matters more than level
A steep drop provokes attacks even from a modest peak.
Classic experimental evidence
Artificial estrogen withdrawal reliably reproduces menstrual migraine.
Somerville's priming experiments proved the drop itself is the trigger.
Trigeminal Sensitization
Estrogen withdrawal raises excitability in trigeminal and cortical neurons.
- Increased: CGRP release (pro-nociceptive peptide)
- ERα / ERβ: Trigeminal ganglion receptors (dense estrogen-receptor expression)
- Threshold lowered: Cortical spreading depression (easier to trigger)
- Reduced: Pain threshold (across trigeminovascular system)
Estrogen receptors on trigeminal neurons
Falling estrogen removes a protective, stabilizing neural signal.
CGRP and neurogenic inflammation
Sensitized neurons release more calcitonin gene-related peptide.
Cortical excitability rises
Lower estrogen makes cortical spreading depression easier to trigger.
Sensitization builds silently before any headache pain appears.
Menstrual Migraine Attack
The estrogen-withdrawal trigger produces a longer, more severe migraine attack.
- Up to 72h: Attack duration (longer than average attack)
- More disabling: Severity (vs non-menstrual migraine)
- ~70% of cycles: Recurrence (in true menstrual migraine)
- Often lower: Triptan response (more treatment-resistant)
A predictable, cyclical attack
Menstrual migraine recurs tightly around the perimenstrual window.
Greater severity and duration
These attacks tend to last longer and hurt more.
Preventive strategies
Perimenstrual estrogen supplementation can blunt the withdrawal trigger.
Stabilizing the hormone drop, not just treating pain, prevents attacks.