This study evaluate role of tranexamic acid in reducing blood loss among pregnant women undergoing cesarean section because of placenta previa .Half of participants will receive tranexamia acid drug While the other half will receive placebo.

Tranexamic Acid used in the field of obstetrics to decrease blood loss during and after cesarean section .

Tranexamic Acid is an antifibrinolytic agent which cause reversible and competitive blockade of the lysine binding sites in plasminogen molecules . It is a synthetic analog of amino acid lysine and its action is to reduce blood loss

Inclusion Criteria:

• age 18 -38 Body mass index <30 , Diagnosis of placenta previa

Exclusion Criteria:

• patient with bleeding disorder , hepatic and renal disease. contraindication to tranexamic acid as allergy , hypersensitivity to tranexamic acid and known thromboembolic event during pregnancy .

other causes ofantepartum haemorrhage eg :accidental haemorrhage, rupture uterus.

type 1,2 of placenta previa anterior type 3,4 of placenta previa posterior causes of overdistended uterus like :multiple pregnancy, polyhydraminos