Abnormal uterine bleeding (AUB) is defined as bleeding from uterine corpus that is abnormal in duration, volume, frequency and/or regularity. Due to immaturity of the hypothalamic-pituitary-ovarian (HPO) axis, AUB is common in adolescents. \[1\] Furthermore, inherited or acquired bleeding disorder may further intensify the existing hormonal imbalance and increase morbidity of the underlying condition.
In addition to these problems, hyperprolactinemia, thyroid disorders and polycystic ovary syndrome (PCOS) are the common underlying endocrine disorders. \[2\] Abnormal Uterine Bleeding decreases quality of life, affects school attendance and limits sports and social activity participation. \[3\] The normal menstrual cycle depends on the feedback loops of estrogen and progesterone on the production of luteinizing hormone and follicle-stimulating hormone by the pituitary gland and on the hypothalamus's normal function as metronome for the hypothalamic-pituitary- ovarian axis. \[4\] Differential diagnosis of abnormal uterine bleeding in adolescents: Bleeding disorders: (Von Willebrand disease, Platelet dysfunction Thrombocytopenia, Clotting factor deficiency) Endocrine causes: (Anovulatory bleeding, Polycystic ovary syndrome, Thyroid disorders, Hyperprolactinemia ).
Gynacological causes: (Adenomyosis, leiomyoma,polyp, malignancy, ovulatory dysfunction)(5) Medications: (Anticoagulants, Depot medroxyprogesterone, implants Intrauterine devices). \[7\] A woman's monthly menstruation takes a large toll on the hemostatic system. To avoid excessive bleeding. Any quantitative or qualitative disruption of the hemostatic
system can lead to increased menstrual bleeding. Primary hemostasis: involves the integration of platelets and von Willebrand factor (VWF). Initiation of primary hemostasis begins with injury to the blood vessel wall.
This injury allows exposure of collagen, elastin, and VWF causes platelets to activate and bind to VWF. Platelets are activated to signal further platelet activation and aggregation , which leads to the formation of the primary hemostatic plug. \[8\] Secondary hemostasis involves coagulation proteins called factors, the blood vessel wall, and fibrin. Endothelial wall injury causes the release of tissue factor ,which activates factor(F)VII to the activated form, FVIIa.15 The tissue factor/FVIIa complex activates the remainder of the coagulation cascade and the formation of thrombin. The final step is the activation of FXIII ,which cross links fibrin chains to form the fibrin clot. Anticoagulants, such as protein C,S , and antithrombin, as well as plasmin, help balance this procoagulant state and prevent excessive thrombus formation. \[9\] Most adolescents need outpatient management and reassurance that their menstrual cycles would become cyclic and ovulatory over time. However, treatment is required when AUB causes anemia or impairs quality of life . In these girls, the first line treatment is generally medical. Acute AUB patients who are clinically unstable, have active bleeding or severe anemia should be hospitalized for management A clinical decision should be made regarding intravenous crystalloid and blood or blood product transfusions, hormone treatment, and iron replacement, according to the severity of bleeding, clinical condition of the patient, hemodynamic stability and the underlying medical problem. If an underlying cause can be identified, appropriate specific treatment should be given
