Primary atony of the lower uterine segment as a distinct cause of early postpartum haemorrhage: a case series and management recommendations.

Primary atony of the lower uterine segment appears to be a distinct cause of postpartum haemorrhage. We report a case series of women with postpartum haemorrhage where ultrasound and clinical findings revealed a well contracted fundus and upper uterine segment and a ballooned out lower uterine segment, a condition we have called primary atony of the lower uterine segment. We hope that this case series will lead to increased recognition of this condition, stimulate others to report their experience and lead to additional studies to better characterise this entity, and develop more effective therapies.