studying the effect of different uterotonic agents in prevention of postpartum hemorrhage following cesarean section in high risk cases.

INTERVENTION: pregnant women undergoing cesarean section and at high risk to develop post partum hemorrhage. All the patients will be subjected to the following after taking informed written consent: 1. Full history taking. 2. General examination including patient weight. 3. Abdominal examination including obstetric ultrasound. 4. Routine laboratory tests including hemoglobin and hematocrit. 5. Anesthesia technique will be standardized, spinal anesthesia will be performed. Patients will receive an intravenous bolus of 500 mL crystalloid before spinal anesthesia. A size 25G pencil‐point needle will be used at a suitable lumbar inter‐space. The patient can be sitting or in the left lateral position for spinal anesthesia. The anesthetic solution consisted of 2 ml 0.5% hypertonic bupivocaine (2.2 ml in the sitting position), 10–20 microgram fentanyl and 0.1 mg preservative free morphine. Anesthesia should be to the level of T5, as assessed by touch. The patient will be tilted 15 degree to the left of supine and standard monitoring used as per the AAGBI guidelines. Anesthetists will replace blood loss at operation with colloid infusion or blood when deemed necessary. Intravenous crystalloids were continued at 1 Litre every 8 hours until the morning after surgery. 6. The patients will be divided randomly in to 3 GROUPS: * GROUP 1:80 patients will receive 100 microgram of PAPAL (carbetocin) IV as a uterotonic agent after delivery of fetal anterior shoulder. * GROUP 2:80 patients will receive 5 IU of IV bolus oxytocin then will be followed by 40 IU of oxytocin infusion on 1000 ml saline with a rate of 150 ml per hour as a uterotonic agent after delivery of fetal anterior shoulder. * GROUP 3:80 patients will receive 800 microgram misoprostol rectally immediately after anesthesia and before Cesarean Section followed by 5 IU of oxytocin IV bolus immediately after delivery of anterior shoulder as a uterotonic agent. 7. Active management of the third stage of labour as the following: * Administration of the uterotonic agent with delivery of the anterior shoulder of the baby. * Clamping and cutting the umbilical cord soon after birth. * Applying controlled cord tension to the umbilical cord while applying simultaneous counter‐pressure to the uterus, through the abdomen. 8. The surgical approach to cesarean section is standardized. Surgeons will be asked to operate to a standard procedure that specifies transverse lower segment ceserean section two layer closure of the uterine incision, and to avoid delivering the uterus for suturing unless clinically indicated. 9. Follow up the patients postoperative regarding vital signs and hemoglobin and hematocrit 48 hours after surgery CONDITION: Postpartum hemorrhage following cesarean section PRIMARY OUTCOME: * The need of uterine massage among the three groups. * To compare the incidence of major obstetric hemorrhage ; ( bleeding equal to or greater than 1000 ml following use of different uterotonic agent). ; ; Major obstetric hemorrhage will be defined by: ; 1‐measured blood loss as calculated from pre and postoperative haematocrit as following formula: ; ; This estimate was based on the difference between the preoperative and postoperative packed cell volume (PCV), and is calculated as follows: ; ; Calculated estimated blood loss is equal to estimated blood volume × (preoperative PCV ‐ postoperative PCV)/preoperative PCV ; ; (Where estimated blood volume is equal to booking weight (kg) × 85) ; ; * To compare the need for an additional uterotonic agent between the three groups. ; ; SECONDARY OUTCOME: To compare the need for blood transfusion and/or blood products. ; We have chosen this calculation as a quantitative objective measure to estimate hemorrhage because it is widely accepted that clinicians underestimate blood loss and that gravimetric methods include liquor in addition to blood, which limits accuracy. ; We chose the use of an additional uterotonic agent as a primary outcome because obstetricians are likely to intervene in the event of uterine atony and use an additional agent to prevent hemorrhage. ; ‐ To compare the estimated mean operative blood loss between the two groups (as measured by theatre staff) Disposable waterproof drapes are in use with pockets that capture all body fluids. The suction volume is measured. All swabs are weighed to measure additional blood loss. ‐ To compare the incidence of severe anaemia (Hb fall equal to or greater than 20%) 48 hours after delivery between the three groups by serum assay (or patient transfused) . ; ‐ To compare the incidence of side effects (vomiting,hypotension). ‐ To compare the objective change in hemoglobin and hematocrit ; before and 48 hours after delivery between the three groups by complete blood picture assay . ; INCLUSION CRITERIA: pregnant full term women that are scheduled to undergo ceserean section and have at least ONE of following (high risk patients for PPH) . 1. Past history of PPH. 2. Antepartum hemorrhage (eg placenta previa and accidental hemorrhage. 3. Over distension of the uterus (polyhydraminos, multiple pregnancy and macrosomia. 4. Intra‐amniotic infection. 5. Uterine muscle exhaustion (prolonged labour and high parity). 6. Anatomical uterine anomalies and uterine fibroid.