The purpose of this study was to evaluate that the tranexamic acid (TXA)Intravenous and oral, is equivalent oxytocin (OXY),intramuscularly, in reducing the blood loss in post partum period (mL) in patients at the end of pregnancy ( 37-42 w ) at low risk of post partum hemorrhage (PPH). The PPH means a blood loss equal to or greater than 500 ml after a vaginal delivery (the bleeding is defined severe if it exceeds 1000 mL). PPH is called "primary" when blood loss arose within 24 hours after birth.

This trial includes three arms of treatment :

• arm A (IMP1Test): TXA 500 mg/ 2 vials (1 gr) slow intravenous infusion 1ml/min within 5 minutes from the delivery(third stage af labor)
• arm B (IMP2Control): OXY 5 IU/ml/ 2 vials (10 International Unit) intramuscularly within 5 minutes from the delivery (third stage af labor) The clamping of the umbilical cord will be executed immediately after birth.

The randomization 1:1 (block design), generated by the computer.

Primary outcomes: assessment of total blood loss expressed in mL:

• immediately after delivery
• two hours after delivery

The measurement of the overall blood loss at delivery (ml) will be performed by the graduated bag, immediately after birth.

The measurement two hours after delivery will be performed by weighing of the adsorbent material [ N.ml = N. gr indicated by the balance - dry weight of the sanitary napkin]. The overall loss in blood measured (ml) two hours of delivery will then be performed by adding the two collections.

Inclusion Criteria:

• Subjects at the end of pregnancy ( 37-42 w ) at low risk of PPH Mean by low-risk of PPH subjects without any of the following risk factors : hypertension/preeclampsia, placental abruption during pregnancy , placenta previa , tocolysis two hours before delivery, multiple pregnancy , previous PPH, obesity ( BMI > 35 ), anemia (Hb < 7 g/dL), elective caesarean section , induction of labor, retention of placental material , polyhydramnios , fever during labor, use of high doses of heparin low molecular weight.
• Subjects full capacity and the willingness to give written informed consent .

Exclusion Criteria:

• Subjects with preterm pregnancy (<37 weeks ) or with prolonged pregnancy ( > 42 weeks )
• Subjects at the end of pregnancy ( 37 weeks - 42 weeks ) with the following risk factors for PPH (Tab1.Protocol Study, vers.2.0 of 07/05/2016)
• multiple pregnancy
• History of thromboembolic disease or high incidence of thromboembolic events in family history ( patients at high risk of thrombophilia )
• Patients with Long - QT syndrome or who are taking drugs that cause QT prolongation
• Intrauterine fetal Death
• Epilepsy
• Autoimmune disease Tab1 medical history :
• Placental abruption during pregnancy
• Placenta previa
• Hypertension / preeclampsia
• Previous PPH
• Polyhydramnios
• Obesity ( BMI > 35 )
• Anemia ( < 7 g / dL )