Uterine Atony

Uterine atony is the inability of the uterus to contract after childbirth, which may lead to continuous bleeding, and it is the leading cause of postpartum hemorrhage, accounting for about 70 percent of cases. Normally the uterus's muscular contractions after delivery stop blood flow from the vessels that had supplied the placenta during pregnancy; when this mechanism fails, severe bleeding can result, making uterine atony the most common preventable cause of maternal death from postpartum hemorrhage worldwide. Oxytocin is the primary medication used to prevent it, with ergotamine and uterine massage used as additional treatments to encourage contraction.