Upon oxytocin binding,OXTR activates Gq, leading to Ca2+ release from intracellularstores, which promotes myometrial smooth muscle contraction.10 OXTR signaling through Gq is counteracted bycoupling to β-arrestin, which mediates desensitization and internalizationof OXTR from the cell surface.11−14 OXTR desensitization after oxytocin exposure mayimpair myometrial contractions, leading to adverse events includinguterine atony and postpartum hemorrhage.6−8. Here, OXTR is linked to hemorrhage.