the prevalence of pre-menstrual acne among kermanshah women (2007)

background: acne as the most common disease of pilosebaceous unit is a chronic inflammatory disease, which usually subsides spontaneously around the age of 25. however, premenstrual acne recurs in women before menstruation even until the menopause.  there are different prevalence rate of pre menstrual acne in literature, and there are few studies in this field in iran. this study aimed to evaluate the prevalence of the pre menstrual acne among women in kermanshah city in 2007. methods: in this descriptive study, 400 women with acne were assessed using checklist, which was completed by dermatologists. the collected data were statistically analyzed using descriptive statistics and spss software. results: the prevalence of the new acne lesions during a menstrual cycle was 79.5%. new acne lesions occurred in pre-menstrual period in 75% of patients, mostly 7 days (in 28%) and 2-3 days (in 18.3%) before menstruation. conclusion: regarding the high prevalence of premenstrual acne, further evaluations of predisposing and exacerbation factors and its controlling methods is recommended.