Dysfunctional Uterine Bleeing (DUB) is the most common cause of functional abnormal uterine bleeding, which is abnormal genital tract bleeding based in the uterus and found in the absence of demonstrable organic pathology. Diagnosis must be made by exclusion, since organic pathology must first be ruled out. It can be classified as ovulatory or anovulatory, depending on whether ovulation is occurring or not.