What is the recommended tranexamic acid (TXA) dosing regimen for first‑trimester bleeding compared with full‑term postpartum hemorrhage, and what contraindications must be confirmed before use?

TXA Dosing for First-Trimester Bleeding vs Full-Term Postpartum Hemorrhage

Tranexamic acid is NOT recommended for first-trimester bleeding, as all current evidence and guidelines address only postpartum hemorrhage treatment; for full-term postpartum hemorrhage, administer 1 gram IV over 10 minutes within 3 hours of birth, with a second 1 gram dose if bleeding continues after 30 minutes or restarts within 24 hours. 1

Critical Distinction: No Evidence for First-Trimester Use

The provided evidence contains no guidelines or research supporting TXA use for first-trimester bleeding. All recommendations specifically address postpartum hemorrhage occurring after delivery. 1, 2, 3

Postpartum Hemorrhage Dosing (Full-Term)

Standard Dosing Regimen

• Initial dose: 1 gram (100 mg/mL) IV administered at 1 mL/min over 10 minutes 1, 2
• Second dose: 1 gram IV if bleeding continues after 30 minutes OR if bleeding restarts within 24 hours of the first dose 1, 2

Critical Timing Requirements

• Administer within 3 hours of birth for any benefit—this is an absolute threshold 1, 3
• Effectiveness decreases by approximately 10% for every 15-minute delay in administration 1, 3
• No benefit is seen after 3 hours post-birth, and administration beyond this window may be harmful 1
• Give TXA as soon as possible after diagnosing PPH—earlier administration increases survival benefit 1, 4

Indications for Use

• TXA should be given in all cases of postpartum hemorrhage regardless of etiology (uterine atony, genital tract trauma, retained tissue) 1, 3
• Clinically diagnosed PPH is defined as estimated blood loss >500 mL after vaginal birth or >1000 mL after cesarean section, or any blood loss compromising hemodynamic stability 1

Contraindications to Confirm Before Use

Absolute Contraindication

• Known thromboembolic event during pregnancy (e.g., deep vein thrombosis, pulmonary embolism) 1, 2
• Active intravascular clotting 2

Safety Considerations

• TXA does not increase the risk of maternal thrombotic events when used appropriately for PPH 5, 6
• The primary safety concern in practice is accidental intrathecal injection from look-alike medication errors, which has caused maternal deaths—implement strict medication safety protocols 5

Administration Route

• Intravenous only—the WHO recommendation applies exclusively to IV administration 1, 2
• Benefits and harms of other routes (oral, intramuscular) remain a research priority and are not currently recommended 1

Clinical Decision Algorithm

1. Diagnose PPH: Blood loss >500 mL (vaginal) or >1000 mL (cesarean), or hemodynamic compromise 1

2. Check contraindications: History of thromboembolic events during pregnancy or active intravascular clotting 1, 2

3. Assess timing: Calculate hours since birth—if <3 hours, proceed; if ≥3 hours, do NOT give TXA 1

4. Administer first dose: 1 gram IV over 10 minutes immediately 1, 2

5. Reassess at 30 minutes: If bleeding continues, give second 1 gram dose IV 1

6. Monitor for 24 hours: If bleeding restarts within 24 hours, give second dose (if not already administered) 1

Common Pitfalls to Avoid

• Do not delay TXA administration while waiting for laboratory results or attempting other interventions first—give it immediately alongside oxytocin and uterine massage 3
• Do not give TXA beyond 3 hours post-birth, as this may cause harm without benefit 1
• Do not withhold TXA based on presumed etiology—it should be given for all PPH regardless of whether bleeding is from atony, trauma, or other causes 1, 3
• Do not confuse with prevention: TXA is not recommended for routine prophylaxis during vaginal or cesarean delivery in women without active bleeding 5, 6, 7