Carbetocin is a synthetic long-acting oxytocin 8-peptide analogue with agonist properties, and its clinical and pharmacological properties are similar to those of naturally produced oxytocin. Like oxytocin, cabetocin binds to the oxytocin receptor of uterine smooth muscle, causing rhythmic contractions of the uterus, increasing its frequency and increasing uterine tension on the basis of the original contraction of the Chemicalbook. In non pregnancy conditions, the content of oxytocin receptors in the uterus is very low, increasing during pregnancy and reaching a peak during delivery. Therefore, cabetoxin has no effect on non pregnant uterus, but has an effective uterine contractile effect on pregnant uterus and newly born uterus.