Postpartum Hemorrhage

Postpartum hemorrhage is excessive bleeding after childbirth, defined as blood loss >500 mL after vaginal delivery or >1000 mL after cesarean delivery, and can lead to maternal morbidity and mortality if not promptly managed.

Definition

Postpartum hemorrhage is excessive bleeding after childbirth, defined as blood loss >500 mL after vaginal delivery or >1000 mL after cesarean delivery, and can lead to maternal morbidity and mortality if not promptly managed.

Epidemiology

Occurs in 2–5% of all deliveries
Major cause of maternal mortality worldwide, especially in low-resource settings
Higher incidence in multiparity, prolonged labor, and multiple gestation
Contributes significantly to postpartum anemia and shock
Early recognition and management reduce maternal complications

Etiology

Primary (within 24 hours of delivery): uterine atony, genital tract trauma, retained placenta, coagulation disorders
Secondary (24 hours to 12 weeks postpartum): infection, retained products, subinvolution of the uterus
Risk factors: prolonged labor, oxytocin use, multiple gestation, polyhydramnios, prior PPH, cesarean section
Coagulopathies (pre-existing or acquired) increase risk
Placenta previa or placenta accreta in complicated pregnancies

Pathophysiology

Uterine atony leads to failure of myometrial contraction and continued bleeding
Trauma to birth canal, cervix, or perineum can cause vascular injury
Retained placental tissue prevents adequate uterine contraction
Coagulation defects impair hemostasis and prolong bleeding
Secondary PPH involves delayed uterine involution or infection