Postpartum Haemorrhage — WHO 2025 Definition, Causes, Prevention and Stepwise Management

Postpartum haemorrhage (PPH) is excessive bleeding after childbirth. WHO estimates that it causes nearly 45 000 deaths a year, and it remains one of the leading causes of maternal mortality worldwide, with about 80% of PPH deaths in low- and middle-income countries, particularly sub-Saharan Africa and South Asia.

The abnormal haemodynamic signs in the WHO 2025 criteria are pulse > 100 bpm, shock index > 1, systolic BP < 100 mmHg or diastolic BP < 60 mmHg. WHO asks for particular vigilance in the first 2 hours after birth, because most bleeding events meeting the criteria occur in that window.

The WHO 2025 diagnostic criteria and first-response bundle are written for bleeding within 24 hours of birth, i.e. primary PPH. StatPearls lists secondary PPH among the situations — with placental abruption and pre-eclampsia — in which coagulation studies and fibrinogen are useful because DIC may be present.

WHO describes four primary causes — uterine atony, genital tract trauma, retained placental tissue and coagulation abnormalities — remembered as the 4 Ts: Tone, Trauma, Tissue and Thrombin. A structured approach that checks each one rapidly is the basis of first-response care.

Most women who have PPH have no identifiable risk factor, which is why WHO insists on prophylactic uterotonics and blood-loss measurement for every birth. Anaemia does not cause PPH but makes the same blood loss far more dangerous.

The third stage of labour — from the birth of the baby to complete delivery of the placenta — is the critical window. WHO 2025 recommends a quality-assured uterotonic for every birth, using only one of oxytocin, carbetocin or misoprostol.

WHO's treatment sequence: IV oxytocin first; if it is unavailable or bleeding does not respond, give IV ergometrine, the oxytocin–ergometrine combination, or a prostaglandin (including sublingual misoprostol 800 µg).

WHO recommends early IV tranexamic acid (TXA), within 3 hours of birth, in addition to standard care, for all women with PPH after vaginal or caesarean birth — regardless of whether the bleeding comes from trauma or atony.

• Dose: 1 g IV (100 mg/mL) at 1 mL per minute, i.e. over 10 minutes.
• Second dose: another 1 g if bleeding continues after 30 minutes, or restarts within 24 hours of the first dose.
• Clock starts at birth, not at diagnosis. If the time of birth is unknown, use the best estimate.
• Not after 3 hours: pooled data from 40 138 bleeding patients showed no benefit beyond 3 hours, with point estimates in the direction of harm — WHO does not support TXA more than 3 hours after birth.
• Avoid with a clear contraindication to antifibrinolytics (e.g. a known thromboembolic event in pregnancy).

TXA is an antifibrinolytic. The WOMAN trial was designed because early TXA had already been shown to reduce deaths from bleeding in trauma patients. Note the exam distinction: TXA is for treatment of PPH (within 3 h), not for routine prevention.

WHO recommends a standardized, timely approach for every vaginal birth: objective measurement of blood loss (for example with a calibrated drape) plus a first-response treatment bundle started as soon as PPH is diagnosed, rather than one intervention at a time.

1. Massage of the uterus.
2. Oxytocic drugs to make the uterus contract.
3. Tranexamic acid to reduce bleeding.
4. Intravenous fluids — isotonic crystalloids in preference to colloids.
5. Vaginal and genital tract examination.
6. Escalation of care if bleeding persists.

For retained placenta, WHO recommends a uterotonic only if PPH is present, antibiotic prophylaxis for manual removal, and preparing for manual removal if the placenta is still undelivered after 30 minutes without PPH.

About 10–20% of women do not respond to the first-response bundle (WHO). Uterine atony remains the leading cause in these refractory cases. Management moves from temporizing measures that buy time, to conservative surgery, to hysterectomy.

The B-Lynch suture, a brace-like suture placed over the uterus, has been used since 1989 for bleeding from uterine atony that has failed conservative management, and it allows the uterus to be conserved for future menstruation and pregnancy. WHO's sequence: compression sutures first; if they fail, uterine, utero-ovarian and hypogastric vessel ligation; if life-threatening bleeding continues, subtotal or total hysterectomy.

A shock index above 1 simply means the pulse rate is higher than the systolic BP. Combined with objectively measured blood loss of ≥ 300 mL, a shock index > 1 (or pulse > 100, SBP < 100 or DBP < 60) already meets the WHO 2025 criteria for starting the first-response bundle — the woman does not have to reach 500 mL first.

• Fluids: isotonic crystalloids rather than colloids for initial resuscitation (WHO).
• Blood products: the decision to transfuse should rest on the underlying risk, continuous clinical and haematological assessment and clear protocols (WHO 2025); early activation of massive-transfusion protocols is emphasised in StatPearls.
• Cell salvage: only in the context of rigorous research (WHO 2025).
• After PPH: oral iron with or without folic acid for 6–12 weeks where anaemia is common; IV iron when oral iron is not tolerated or rapid correction is needed.

• Definition — 500 mL vaginal / 1000 mL caesarean; primary < 24 h, secondary 24 h to 12 weeks.
• Most common cause — uterine atony (Tone).
• Drug of choice for prevention and treatment — oxytocin; dose 10 IU IM/IV.
• Contraindications — ergometrine in hypertension; carboprost in asthma.
• Tranexamic acid — 1 g IV over 10 min within 3 h of birth; repeat after 30 min if needed.
• Surgical sequence — B-Lynch, uterine artery ligation, internal iliac ligation, hysterectomy.
• Bleeding with a contracted uterus — genital tract trauma.