Abnormal uterine bleeding (AUB, also referred to as menstrual bleeding irregularities) is the abnormality of menstrual bleeding in terms of quantity, frequency and pattern. The reproductive and postmenopausal periods are the most common reasons for admission to the gynecology outpatient clinic and negatively affect women’s physical, psychological, emotional and sexual quality of life (1,2). Abnormal uterine bleeding is an important health problem in women that can lead to loss of productivity and increase in healthcare costs (3). The International Federation of Gynecology and Obstetrics (FIGO) created the PALM-COEIN classification system in 2011 to collect the etiologies of AUB under one title. PALM is used to group structural causes, while COEIN is used to classify non-structural causes. The purpose of this classification is to eliminate the ambiguity by gathering AUBs in a terminology (4). Although some reasons that play an organic, endocrinological, autoimmune, immunological, metabolic and structural role in the etiology of abnormal uterine bleeding have been revealed, the cause of bleeding is not known clearly in the vast majority of patients. The patient group in whom organic, structural, immunological and endocrine causes cannot be found is defined as dysfunctional uterine bleeding (DUB) (5).
