Inclusion Criteria:

• Age ≥ 18 years.
• After Vaginal or C/S delivery.
• Need prophylactic treatment in a preventive dose.
• Presence of one or more high risk factors: Active infection, IBD, Heart disease, Type 1 diabetes with nephropathy, IV drug user, Surgical operation in Postpartum period, Emergency cesarean section.

OR presence of 2 low risk factors: Age > 35, post-partum hemorrhage > 1000 ml, Cesarean section, Hysterectomy, BMI > 30, Multiparity- Third birth or more, Active Smoking, Obstetric complications in current pregnancy (including preeclampsia, preterm birth before 37 weeks, active infection including chorioamnionitis, prolonged labor over 24 hours), Twin birth, Immobility, Large varicose veins, Stillbirth

Exclusion Criteria:

• Breast feeding.
• Predispose to hypercoagulability
• Familial history of VTE.
• Antiphospholipid syndrome (APS).
• Prior VTE.
• Anticoagulant treatment before or during pregnancy.
• BMI > 40
• History of severe renal or hepatic disease.
• Use of selective serotonin reuptake inhibitors or serotonin-norepinephrine reuptake inhibitors.
• Known diagnosis of bleeding dyscrasia (eg, von Willebrand disease).
• Spinal/epidural hematoma or spinal puncture.
• Active pathological bleeding or high risk of bleeding.
• Hemoglobin > 9 mg/dl before the delivery.