Secondary Postpartum Hemorrhage

Summary

Secondary PPH is a potentially life-threatening condition most often caused by retained products of conception, subinvolution of the placental site, or infection. Diagnosis relies on clinical features, imaging, and laboratory evaluation. Management requires a tailored approach that combines medical therapy, surgical interventions, and supportive care, with hysterectomy reserved for refractory, severe bleeding. Prompt recognition and multidisciplinary management are essential to reduce maternal morbidity and mortality.

Definition

Secondary postpartum hemorrhage (PPH) is defined as abnormal or excessive vaginal bleeding occurring between 24 hours and 12 weeks after delivery. It is less common than primary PPH but can be life-threatening if not promptly recognized and treated.

Etiology and Pathophysiology

The major causes of secondary PPH include:

1. Retained Products of Conception (RPOC)

• Risk factors: Placenta accreta, retained placenta, preterm birth, multiple gestations, and assisted vaginal delivery.

• Clinical features: Abnormal uterine bleeding, fever, lower abdominal pain, amenorrhea.

• Diagnosis:

• Ultrasound: thickened endometrial echogenic complex or focal intrauterine mass.

• Color Doppler: vascularity within endometrial material (key finding).

• Management:

• Medical: uterotonic agents (e.g., prostaglandin E1 analogs).

• Surgical: dilation and curettage (D&C) or hysteroscopic removal.

2. Subinvolution of the Placental Site

• Risk factors: Multiparity, cesarean delivery, uterine atony, endometritis, coagulopathy, RPOC.

• Clinical features: Heavy bleeding, usually in the second week postpartum; fever, abdominal pain, signs of hypovolemia.

• Diagnosis:

• Ultrasound: hypoechoic tortuous myometrial vessels.

• Doppler: increased peak systolic velocity.

• Histology (confirmatory): dilated myometrial arteries with thickened walls and thrombosis.

• Management:

• Uterotonics (e.g., IV oxytocin).

• Surgical: D&C, vacuum removal.

• Severe bleeding: uterine artery embolization or hysterectomy.

3. Postpartum Endometritis

• Risk factors: Cesarean delivery, prolonged rupture of membranes, prolonged labor, multiple cervical exams, meconium-stained fluid, retained tissue, low socioeconomic status.

• Clinical features: Fever, chills, malaise, abdominal pain, uterine tenderness, foul-smelling lochia.

• Diagnosis: Clinical features supported by cultures (blood, urine, vaginal discharge).

• Management:

• IV antibiotics (clindamycin + gentamicin).

• Uterine evacuation if RPOC present.

• Hysterectomy for refractory, life-threatening infection.

4. Coagulation Disorders

• Acquired: HELLP syndrome, sepsis, intrauterine fetal demise.

• Inherited: von Willebrand disease, hemophilia, factor deficiencies (e.g., XIII).

• Clinical features: Mucocutaneous bleeding, GI bleeding, menorrhagia, oozing from wounds or IV sites.

• Diagnostics: CBC, PT, aPTT, fibrinogen, D-dimer, vWF antigen and activity.

• Management:

• Blood product transfusion (FFP, platelets).

• Factor replacement (specific concentrates).

• Pharmacological therapy: desmopressin, antifibrinolytics.

5. Rare Causes

• Disseminated Intravascular Coagulation (DIC): Often triggered by placental abruption, preeclampsia, amniotic fluid embolism, or prolonged fetal demise. Requires ICU care, removal of inciting cause, and selective blood product replacement.

• Unexplained Hemorrhage: If no correctable cause is found, surgical measures may be required, including uterine or internal iliac artery ligation or hysterectomy as a last resort.

Epidemiology

• Secondary PPH most often occurs in the second week postpartum.

• Endometritis and RPOC are the most common causes.

• Subinvolution accounts for ~13% of cases.

Clinical Features

• Abnormal, often heavy or recurrent vaginal bleeding after the first 24 hours postpartum.

• May be associated with fever, lower abdominal pain, uterine tenderness, and signs of anemia or hypovolemia.

Diagnosis

• Clinical evaluation: bleeding severity, systemic symptoms.

• Imaging: ultrasound ± Doppler for RPOC or subinvolution.

• Laboratory studies: CBC, coagulation profile, blood cultures when infection is suspected.

• Histopathology: rarely required but confirmatory for subinvolution.

Management Principles

1. Stabilization: Resuscitation with IV fluids, blood products if needed.

2. Targeted treatment:

• Endometritis: IV antibiotics ± uterine evacuation.

• RPOC: Uterotonic drugs, D&C, or hysteroscopic removal.

• Subinvolution: Uterotonics, surgical evacuation, embolization, hysterectomy in severe cases.

• Coagulopathy: Factor replacement, desmopressin, transfusion support.

• Rare causes (DIC, inversion): Specific corrective measures with ICU support.