Postpartum Hemorrhage: Prevention and Management

Postpartum haemorrhage (PPH) — excessive bleeding after birth — is among the leading direct causes of maternal death worldwide, and most events stem from a uterus that fails to contract adequately after the placenta delivers. Because it can arise quickly in women who were previously well, prevention through active management of the third stage of labour, early recognition, and prompt escalation are central concerns of midwifery and obstetric care.

Definition

Postpartum haemorrhage is excessive blood loss following childbirth, conventionally defined as blood loss of 500 mL or more after vaginal birth (or 1000 mL or more after caesarean), or any blood loss sufficient to cause haemodynamic compromise; early (primary) PPH occurs within 24 hours and late (secondary) PPH from 24 hours to about 6-12 weeks after birth.

Scope

This topic covers what postpartum haemorrhage is, its causes and risk factors, its epidemiological burden, and the evidence underpinning prevention (notably uterotonic prophylaxis and active management of the third stage) and treatment principles (including tranexamic acid). It is reference-educational: it describes the evidence base and is not a dosing guide or a substitute for institutional protocols or individualized clinical care.

Core questions

• What defines postpartum haemorrhage and how are primary and secondary PPH distinguished?
• What are the principal causes and risk factors for PPH?
• How large is the global burden of PPH as a cause of maternal mortality?
• What is the evidence for active management of the third stage of labour in preventing PPH?
• What is the role of tranexamic acid in the treatment of established PPH?

Key concepts

• Uterine atony
• The 'four Ts' (tone, trauma, tissue, thrombin)
• Primary versus secondary PPH
• Active management of the third stage of labour
• Uterotonic prophylaxis
• Tranexamic acid
• Quantitative blood-loss assessment

Mechanisms

After placental separation, haemostasis depends chiefly on contraction of the myometrium, which compresses the spiral arteries supplying the placental bed; failure of this contraction (uterine atony) is the most common cause of PPH. The other major contributors are summarised as the 'four Ts': trauma (genital-tract lacerations), tissue (retained placenta or membranes), and thrombin (coagulation disorders). Active management of the third stage — administration of a prophylactic uterotonic, controlled cord traction, and uterine assessment — promotes contraction and reduces the incidence of severe bleeding. In established haemorrhage, the antifibrinolytic tranexamic acid reduces death due to bleeding when given early.

Clinical relevance

Because PPH is common, often unpredictable, and rapidly progressive, prevention and preparedness are emphasised throughout intrapartum and postnatal care. Evidence supports prophylactic uterotonics and active management of the third stage to reduce severe bleeding, and early tranexamic acid to reduce bleeding-related death once haemorrhage is established. This entry summarises the evidence base for these strategies; it is not a protocol and does not provide doses, regimens, or individualized management instructions.

Epidemiology

Postpartum haemorrhage complicates a substantial minority of births and is a leading direct cause of maternal mortality globally, with the heaviest burden in low-resource settings where access to uterotonics, blood, and emergency care is limited. A systematic review estimated that PPH (blood loss of 500 mL or more) affects on the order of one in ten deliveries, with severe PPH less common but disproportionately responsible for death and serious morbidity.

History

Excessive bleeding after birth has been recognised as a major obstetric hazard for centuries. The modern era brought the systematic use of uterotonic agents and the consolidation of active management of the third stage as a preventive strategy in the late twentieth century, and the WOMAN trial in 2017 established early tranexamic acid as a treatment that reduces death from bleeding, reshaping contemporary guidance.

Debates

How should blood loss after birth be measured?

Visual estimation of blood loss is known to be inaccurate, and there is ongoing discussion about quantitative or gravimetric measurement to improve early recognition of PPH, balanced against feasibility across settings.

Seminal works

• carroli-2008
• begley-2019
• shakur-2017-woman

Frequently asked questions

What is the most common cause of postpartum haemorrhage?

Uterine atony — failure of the uterus to contract adequately after the placenta delivers — is the most common cause; other causes are commonly grouped as trauma, retained tissue, and clotting disorders (the 'four Ts').

How is the third stage of labour managed to reduce haemorrhage?

Active management of the third stage, which includes giving a prophylactic uterotonic and assessing uterine tone, reduces the risk of severe postpartum bleeding compared with expectant management, according to systematic-review evidence.