['We compared migraine features and acute therapy response in menstrually-related migraines (MRMs) and non-menstrually-related migraines (NMRMs).', 'Women with frequent, disabling migraines were prospectively diagnosed with MRM according to the International Classification of Headache Disorders (ICHD-II; N = 107) criteria using a daily electronic headache dairy. Participants received individualized acute therapy while free of prophylactic migraine medications.', 'Repeated measures logistic regression revealed MRMs were longer (23.4 vs. 16.1 hours, odds ratio [OR]\u2009= 1.01, confidence interval [CI] 1.01, 1.02) and more likely associated with disability (85.6% vs. 75.6%, OR = 1.82, CI 1.27, 2.58) than NMRMs. MRMs were also less responsive to acute therapy (two-hour pain-free response = 6.7% vs. 13.4%, OR =\u2009.45, CI .26, .80) and reoccurred more frequently within 24 hours after a four-hour pain-free response (36.0% vs. 19.6%, OR = 2.12, CI 1.27, 3.53) than NMRMs.'] Do menstrual and nonmenstrual migraines differ in women with menstrually-related migraine?