Can postpartum hemorrhage (PPH) precipitate an acute coagulopathy in a woman actively bleeding after delivery, and what monitoring and treatment should be employed?

Postpartum Hemorrhage and Coagulopathy

Yes, postpartum hemorrhage directly causes acute coagulopathy, and this coagulopathy is unpredictable regardless of the underlying etiology—making early monitoring and aggressive fibrinogen replacement critical to prevent progression to massive hemorrhage. 1

Mechanism and Timing of Coagulopathy Development

PPH-induced coagulopathy develops through multiple mechanisms that occur rapidly during active bleeding:

• Hemodilution from massive fluid resuscitation and blood loss depletes clotting factors 2
• Consumptive coagulopathy occurs as clotting factors are consumed during ongoing hemorrhage 3
• Disseminated intravascular coagulation (DIC) should be considered in all severely bleeding obstetric patients and treated aggressively 3, 2
• Hyperfibrinolysis is common in early PPH and contributes to ongoing bleeding 1

The coagulopathy is unpredictable and can occur with any obstetric etiology, making early monitoring essential even when the cause seems straightforward 1. While atonic or traumatic bleeds are less likely to have early coagulopathy unless diagnosis is delayed, you cannot rely on clinical assessment alone 1.

Critical Monitoring Strategy

Fibrinogen is the single most important parameter to monitor, as it is the most common factor deficiency in PPH and declines rapidly:

• Hypofibrinogenemia (fibrinogen <2 g/L) occurs in 17% of cases with blood loss >2000 mL 4
• Fibrinogen <2 g/L with ongoing bleeding is associated with progression to massive obstetric hemorrhage 5
• Target fibrinogen ≥2 g/L during active hemorrhage 6
• Recent evidence suggests fibrinogen levels ≥400 mg/dL (4 g/L) may be needed to prevent PPH progression 2

Point-of-Care Testing

• Viscoelastic hemostatic assays (VHA) should be used in all hospital-based maternity settings 1
• FIBTEM A5 <12 mm on VHA can predict progression to severe hemorrhage 5
• VHA interpretation should focus on the fibrinogen assay, with replacement prioritized 1
• Results should be repeated if bleeding is ongoing 1

A critical pitfall: Secondary coagulopathy is often underestimated and remains untreated, causing progression to more severe PPH 7. Do not wait for laboratory results in severe bleeding—they take 45-60 minutes and delay is dangerous 7.

Blood Component Therapy Algorithm

Initial Transfusion Strategy (Blood Loss <4 Units RBC)

For atonic or traumatic PPH without early coagulopathy on screening:

• Withhold FFP until 4 units of RBC have been given 1
• Early use of cryoprecipitate or fibrinogen concentrate before RBC may be required if coagulopathy is present on early screening 1
• Protocol-led FFP use leads to excessive transfusion in most atonic/traumatic cases 1

Massive Transfusion (Blood Loss >4 Units RBC or >1500 mL)

Once 4 units of RBC are transfused with ongoing bleeding and no coagulation results available:

• Give 4 units FFP and maintain 1:1 ratio of RBC:FFP until hemostatic test results are known 1
• Initiate massive transfusion protocol if blood loss exceeds 1500 mL 6
• Transfuse packed RBCs, FFP, and platelets in fixed ratios to prevent dilutional coagulopathy 3
• Do not delay transfusion waiting for laboratory results in severe bleeding 6, 5

Fibrinogen Replacement

Prioritize fibrinogen replacement with cryoprecipitate or fibrinogen concentrate:

• Give cryoprecipitate or fibrinogen concentrate if fibrinogen <2-3 g/L with ongoing bleeding 4
• Repeated administration is required if bleeding continues 1
• A recent feasibility trial supports using cryoprecipitate before FFP in first-issued hemorrhage packs 1

Platelet Transfusion

• Platelet transfusion is rarely required unless PPH >5000 mL or platelet count <75 × 10⁹/L 1, 4
• Transfuse when platelet count is <75 × 10⁹/L 1

Antifibrinolytic Therapy

Tranexamic acid (TXA) 1 g IV over 10 minutes must be given within 3 hours of birth:

• TXA reduces bleeding-related mortality and should be given in all cases of PPH regardless of etiology 6, 4
• Effectiveness decreases by approximately 10% for every 15-minute delay 6, 4
• Administration beyond 3 hours may be harmful 6
• A second dose of 1 g IV can be given if bleeding continues after 30 minutes or restarts within 24 hours 6, 5

Essential Supportive Measures to Prevent Worsening Coagulopathy

Maintain normothermia—clotting factors function poorly at lower temperatures:

• Warm all infusion solutions and blood products 6
• Use active skin warming 6
• Avoid hypothermia as it significantly impairs coagulation

Additional measures:

• Administer oxygen to achieve arterial saturation ≥95% 6
• Re-dose prophylactic antibiotics if blood loss exceeds 1500 mL 6
• Continue hemodynamic monitoring for at least 24 hours post-delivery 6

Critical Decision Point: When to Stop Blood Components

Withhold blood components if bleeding has stopped, even if laboratory values are abnormal 1. Laboratory and VHA results must be interpreted within the clinical situation—do not transfuse based on numbers alone when hemostasis is achieved 1.