Molar mass:C45H69N11O12S Molar mass: 988.17 Medical use: Medicine of department of gynaecology. Carbetocin is an oxytocic used in obstetrics to control postpartum hemorrhage and bleeding after giving birth, particularly following cesarean section. It is an eight amino acid long analogue of oxytocin. Carbetocin is an agonist at peripherally expressed oxytocin receptors.