Postpartum Hemorrhage Study Guide- Causes, Algorithm, Treatment

Authors: Rebecca Kirby, MD Blake Briggs, MD

Introduction

Postpartum hemorrhage (PPH) is one of the leading causes of maternal morbidity and mortality worldwide and remains a true emergency in both high- and low-resource settings. It’s defined as ≥1000 mL of blood loss or blood loss accompanied by signs or symptoms of hypovolemia within 24 hours after the birth process (1). For practical purposes, if a patient looks bad, she’s hemorrhaging—don’t wait for a measured volume. Let’s review what every EM physician should know about postpartum hemorrhage.

Quick Pathophysiology

Following delivery, uterine contraction compresses blood vessels at the placental site to prevent hemorrhage. Anything that interferes with this contraction—or adding a source of bleeding elsewhere—can lead to PPH. The classic mnemonic is “The 4 Ts”: Tone (uterine atony), Tissue (retained products of conception), Trauma (lacerations, hematomas, uterine rupture, inversion), Thrombin (coagulopathy).

Treatment

“Step 0” is to call OB immediately and have a low threshold to activate hemorrhage protocol/MTP. If you think you will need more than 4 units of PRBC, call for MTP activation. Ensure the patient has two large-bore IV/IO, keep the patient as warm as possible. Treat this like a trauma patient.

Tone (Uterine atony) – Most common cause (~70–80% of cases). This is a board question. Risk factors: prolonged labor, overdistension (twins, polyhydramnios), infection, magnesium sulfate. Bedside uterine exam is classically “boggy” and not firm. In fact, if the uterus is firm but there is bleeding, think another cause.

Initial management is immediate uterine massage—this is both diagnostic and therapeutic. Again, another board question.

Stepwise treatment:

1. Uterine massage (diagnostic + therapeutic)
2. Oxytocin/Pitocin (2)
3. Tranexamic acid (TXA). Give 1 g IV over 10 min within 3 h of birth (repeat once after 30 min if bleeding persists). Supported by WOMAN Trial, WHO, and ACOG (5,6). Early administration reduces mortality.
4. Misoprostol (route per protocol; PR common when vomiting/limited access) (1)
5. Bakri balloon or large Foley inflated with 300–500 mL saline if medical therapy fails
6. Consider uterine packing and possible surgical intervention if uncontrolled bleeding

Tissue (retained placenta or products)

Retained placental tissue prevents uterine contraction and serves as a nidus for ongoing bleeding.

• Inspect the placenta after delivery—missing cotyledons suggest retained tissue.
• Manual exploration and removal under adequate analgesia are often required (7).
• Persistent bleeding despite uterotonic therapy warrants ultrasound evaluation and OB consultation for curettage.

Trauma

Even with a firm, contracted uterus, lacerations or uterine rupture can be the culprit.

• Inspect the cervix, vagina, and perineum for lacerations and repair any tears
• Don’t forget to check for vaginal or vulvar hematomas, which may require drainage.

Consider uterine rupture if there’s sudden severe pain, abnormal fetal tracing (if intrapartum), or massive bleeding. The classic board presentation for uterine rupture is a patient with sudden, severe abdominal pain — often described as “tearing” or “ripping.” These patients have a history of prior C-section, which is the #1 risk factor. Loss of fetal station or cessation of contractions is mentioned in the stem.

Thrombin (coagulopathy)

Bleeding due to clotting abnormalities (primary or secondary).

• Labs: CBC, PT/INR, aPTT, fibrinogen (8).
• Correct abnormalities (i.e. transfuse platelets, cryoprecipitate if fibrinogen low, FFP if prolonged INR/PTT) (9).

PPH is a clinical diagnosis—do not rely on estimated blood loss (often underestimated by >30%).
Look for tachycardia, hypotension, pallor, and continued bleeding despite uterotonic therapy.

Disposition

• ICU: for ongoing bleeding, transfusions, or hemodynamic instability.
• OB floor: for stabilized patients post-intervention. 

References

1. American College of Obstetricians and Gynecologists. ACOG Practice Bulletin No. 183: Postpartum Hemorrhage. Obstet Gynecol.2017;130(4):e168–e186.
2.  Sheehan SR, et al. Oxytocin bolus versus infusion for postpartum hemorrhage prevention. BMJ. 2018;363:k3546.
3. Royal College of Obstetricians and Gynaecologists. RCOG Green-top Guideline No. 52: Postpartum Haemorrhage, Prevention and Management. London: RCOG; 2016.
4. Agrawal M, Saloni. Postpartum haemorrhage and carboprost for its prevention: A narrative review. Cureus. 2024;16(6):e62875.
5. WOMAN Trial Collaborators. Effect of early tranexamic acid on mortality, hysterectomy, and other morbidities in women with postpartum haemorrhage. Lancet. 2017;389:2105–2116.
6. World Health Organization. WHO Recommendation on Tranexamic Acid for the Treatment of Postpartum Haemorrhage. Geneva: WHO; 2017.
7. Weeks AD. The retained placenta. Best Pract Res Clin Obstet Gynaecol. 2008;22(6):1103–1117.
8. Matsunaga S, Takai Y, Seki H. Fibrinogen for the management of critical obstetric hemorrhage. J Obstet Gynaecol Res. 2018;45(1):13–21.
9. Sholapurkar SL. Transfusion practices in obstetric hemorrhage. Obstet Med. 2018;11(2):66–74.