This document discusses abnormal uterine bleeding and its causes and treatment. It begins with an overview of the normal menstrual cycle and mechanisms of menstruation. It then describes abnormal uterine bleeding, including definitions and types such as polymenorrhea, menorrhagia, and metrorrhagia. The document outlines approaches to diagnosis, including history, examination, lab tests, imaging and procedures. It discusses evaluation of endometrial pathology and various organic and dysfunctional causes of abnormal bleeding. Finally, it provides guidance on treatment, including non-hormonal and hormonal medical options as well as surgical interventions.