The objective of this study is to determine the effect of preoperative tranexamic acid administration on amount of blood loss during hysterectomy . This study, clinical trials, double-blind, placebo- control, single center are conducted in Arash women's hospital. Among women underwent hysterectomy 106 patient are entered in this study and randomly divided in two groups (by block randomization). Inclusion criteria: Uterine size <14 cm, hysterectomy for benign pathology, uterine prolapsed and abnormal uterine blooding. Exclusion criteria: History of previous myomectomy, coagulation disorder , history of abnormal coagulation test, thrombophilie, coagulopathy, cardiovascular, tromboemboli and ceasar, renal and liver dysfunction and patients with an allergy to tranexamic acid and BMI>30. Ten minute before surgery 10mg/kg tranexamic acid with 200 cc normal saline is injected Intravenously for intervention group. In control group 200 cc normal saline is administrated . Before and after surgery all of the surgery bands are weighted and the blood volume in suction devise is recorded . six and twenty four hours after hysterectomy, the hemoglobin will checked. Patients are checked for side effects of tranexamic acid (ceasar, peripheral vascular thrombosis, dizziness). All drugs are prepared by anesthesia technisian and patients are divided in two groups by a person who is not a member of the research group and members of this do not known about the kind of drugs .