Double blinded randomized controlled study

Women will be randomized into two groups using COMPUTER-GENERATED RANDOM NUMBER LIST.

264 dark colored envelops will be serially numbered containing the corresponding letter of the corresponding drug that will be used.

Group C: 132 women in the carbetocin group will receive a bolus of 100 μg intravenous injection at delivery of the anterior shoulder.

Group O: 132 women in the oxytocin group will receive 5 IU of oxytocin by slow intravenous injection at delivery of the anterior shoulder.

• All patients will receive general anaesthesia.
• Operation will be carried out by a three year registrar (at least).
• Uterus will be repaired in situ. Primary endpoint: is the amount of blood loss.
• Blood loss will be estimated using the change in Hb% and hematocrit, the actual blood loss will be calculated using the following equation:
• The actual blood loss equals the estimated blood volume X difference between the initial hematocrit and the final hematocrit / the initial hematocrit

Secondary endpoints include:

1. The need for additional uterotonic medication after carbetocin or oxytocin administration.

   - Uterine tone and Uterine fundus level (with respect to the umbilical point, UP) will be monitored during CS, at the end of CS, 2 hours, 12 hours and 24 hours after delivery

   - Additional uterotonic drugs, needed if sufficient uterine tone is not achieved within 5 minutes of oxytocin or carbetocin administration, will include: i. Ergometrine 0.5 mg by slow intravenous injection. ii. Misopristol 1000 micrograms rectally.

2. The need for blood transfusion or operative interventions related to PPH

   - The need for blood transfusion or operative intervention (B-Lynch sutures, uterine artery ligation, internal iliac artery ligation, Hysterectomy) will be considered.

3. The change in hemoglobin and hematocrit post versus pre CS

   - The drop in hemoglobin level and hematocrit will be evaluated by comparing the hemoglobin concentration on admission and 24 hours after delivery.

4. The hemodynamic adverse effects and the cost-benefit of both drugs.

Inclusion Criteria:

• Multiple pregnancy
• Presence of uterine fibroid
• Previous Myomectomy
• Presence of placenta previa
• Past History of PPH
• Fetal Macrosomia
• Polyhydramnios

Exclusion Criteria:

• Hypertension
• Preeclampsia
• Cardiac, Renal, Liver diseases
• Epilepsy
• History of hypersensitivity to Carbetocin