Why can endometriosis trigger migraines?

With endometriosis, your migraines are not an extra symptom, disconnected from the rest. Endometriosis is not just a disease "of the belly." It is an inflammatory disease that affects the whole body ^[2].

The lesions release inflammatory molecules into the blood that travel everywhere, up to the brain ^[3]. The disease affects about 1 in 10 women of reproductive age, nearly 190 million women and girls worldwide ^[1].

Research confirms the link. A large study of more than 20,000 women with endometriosis found migraines about 1.7 times more likely ^[4]. A meta-analysis found the risk raised by about 56% ^[13]. Migraine prevalence reaches roughly 38% with endometriosis, versus 15% without ^[5].

The deeper the endometriosis, the higher the migraine risk. Deep endometriosis (lesions that grow into the tissue) is more strongly linked to migraines than superficial forms ^[6].

Two mechanisms combine. First, hormones. Estrogen acts like a pain thermostat in the brain: steady, it protects; dropping fast, everything goes off balance ^[7].

At the end of the cycle, estrogen falls within a few days ^[8]. Serotonin drops too, a face nerve (the trigeminal nerve) fires and releases a molecule, CGRP, that widens the brain's blood vessels and triggers the throbbing pain ^[7]. With endometriosis, the lesions make their own estrogen ^[2], so the highs are higher and the drops sharper.

This is menstrual migraine (a migraine tied to the cycle, from 2 days before your period to 3 days after it starts) ^[8]. About 60% of women with migraines report a link to their period ^[7], and it is especially strong with endometriosis ^[9].

Second, inflammation. Lesions release inflammatory markers 2 to 5 times higher ^[10], which irritate blood vessels and nerves up to the brain ^[3]. With chronic pain, the nervous system turns up the "volume": this is central sensitization, where pelvic-pain and migraine circuits meet ^[11].

Two beliefs can be harmful. First: "it's stress, it's psychosomatic." No. Endometriosis causes inflammation you can measure in a blood test ^[10][11]. It is not in your head, it is in your biology.

The second is about your safety. The combined pill (with estrogen) is not advised if you have migraine with aura, because it raises the risk of stroke ^[12]. Aura means warning signs before the migraine: visual changes, tingling, trouble speaking. It is overrepresented with deep endometriosis ^[6]. For these women, a progestin-only option is usually preferred.

One last point: paracetamol alone is rarely enough. Taking painkillers more than 10 to 15 days a month can, paradoxically, keep headaches going: this is medication overuse headache ^[14].

There is no single fix, but there are strategies that work, built with your care team.

• Steady the hormones: a continuous progestin like dienogest (the reference endometriosis treatment) removes the estrogen drop that sets off attacks ^[2].
• Treat the attack: triptans (migraine-specific drugs) like sumatriptan; frovatriptan can be taken preventively around your period ^[8]. Anti-inflammatories (NSAIDs) taken around the period also ease pelvic pain.
• Prevent long term: anti-CGRP antibodies (erenumab, galcanezumab) cut migraine days by at least half in about one patient in two ^[15].
• Support your body: magnesium lowers migraine frequency by about 40% ^[15]; vitamin B2, coenzyme Q10 and omega-3s may help.

Complementary approaches (Cefaly neurostimulation, acupuncture, yoga, regular exercise) add to treatment without replacing it ^[15].

To be heard, track your migraines and your cycle over 2 to 3 cycles. You can say: "My migraines follow my cycle, could this be linked to my endometriosis?" You have the right to ask for a second opinion.