OBJECTIVE:The aim of this study was to compare the allodynia score in headache attacks related and not related to menstruation in women diagnosed with menstrually related migraine without aura. BACKGROUND:Allodynia is an important symptom in migraine and has been associated with migraine chronification. No study has yet compared prospectively allodynia in menstrual vs non-menstrual attacks within the same cohort of patients. METHODS:This is a prospective cohort study, where participants had the 12-item Allodynia Symptom Checklist (ASC-12) assessed after 1, 2, 4, and 24 hours from the onset of migraine attacks in 2 different conditions, with menstrual migraine attack (MM+) and with non-menstrual migraine attack (MM-). RESULTS:A total of 600 women with headache complaints were screened from March 2013 to July 2014 in a headache outpatient or headache tertiary clinic. From these, 55 participants were recruited, and 32 completed the study. Participants' mean age was 27 years, BMI was 22.1, menarche age 12 years, migraine history was 11.5 years, and most women were young (ranged from 17 to 44 years of age), were in higher school (13/32 = 41%), single (20/32 = 63%), and used contraceptives (22/32 = 69%). Multiple pairwise comparisons of ANCOVA's test showed significant higher ASC-12 scores in MM+ group compared to MM- group at 2 hours [mean, 95% CI of difference: 2.3 (0.31, 4.7), P = .049)]. For the ASC-12 categorical scores (absent, mild, moderate, and severe) MM+ yielded higher scores than MM- at 1 hour (z = -3.08, P = .021) and 4 hours (z = -2.97, P = .03). CONCLUSION:This study demonstrated that in the patents from tertiary headache center assessed, menstrual-related migraine attacks augment allodynia scores in the beginning of attacks compared to non-menstrual migraine attacks.