The term menstrual migraine refers to migraine that is associated with menstruation by more than chance, but it does not define pathophysiology. Menstrual migraine affects about 20-25% of female migraineurs in the general population, and 22-70% of patients presenting to headache clinics. In women diagnosed with menstrual migraine, perimenstrual migraine attacks are associated with substantially greater disability than their non-menstrual attacks. Loose interpretation of diagnostic criteria has led to conflicting results in studies on prevalence figures, clinical characteristics, and response to treatment. Importantly, clinical trials often do not distinguish between perimenstrual attacks in women diagnosed with menstrual migraine and attacks associated with menstruation by chance. Two pathophysiological mechanisms have been identified: oestrogen withdrawal and prostaglandin release. Although management strategies targeting these mechanisms might be effective, the evidence is not robust. Given how common and debilitating this distinct condition is, more research investment is needed to expand understanding of its pathophysiology and to develop more effective treatment strategies.