Oxytocin Minimum Effective Dose Trial Aims to Optimize Postpartum Hemorrhage Prevention During Cesarean

Postpartum hemorrhage (PPH) remains a leading cause of maternal mortality, particularly after cesarean sections in countries like Brazil. Uterine atony, the failure of the uterus to contract sufficiently after birth, is the most common cause of PPH. Oxytocin is the primary pharmacological agent used for both prophylaxis and treatment of uterine atony due to its uterotonic effects. However, finding the optimal dose is critical; both insufficient and excessive oxytocin doses can compromise patient safety, highlighting a significant gap in current clinical practice regarding precise dosing for this high-risk population.

This adaptive clinical trial is designed to determine the minimum effective dose (ED90) of oxytocin for preventing uterine atony during cesarean sections performed during labor. The study employs a modified up-and-down method, allocating participants randomly and in a masked fashion to one of two sequential groups: a 'rule of three' dosing strategy or a continuous infusion protocol. The primary endpoint is the identification of the oxytocin dose effective in 90% of cases for preventing uterine atony, aiming to refine current dosing guidelines for this critical intervention.