On postoperative day 14 after a low‑transverse cesarean section, should I evaluate for late postpartum hemorrhage and what are the immediate management steps?

Postoperative Day 14 After Cesarean Section: Evaluation for Late Postpartum Hemorrhage

Yes, bleeding on postoperative day 14 after low-transverse cesarean section falls within the definition of late (secondary) postpartum hemorrhage and requires immediate evaluation with transvaginal ultrasound with color Doppler as the first-line imaging study. 1

Definition and Timing

• Late postpartum hemorrhage is defined as any significant uterine bleeding occurring between 24 hours and 6 weeks postpartum, placing day 14 squarely within this diagnostic window. 2, 1
• After cesarean delivery specifically, the most common causes at this timepoint are endometritis (more common after cesarean) and retained products of conception (RPOC), though RPOC are more frequent after vaginal delivery (32.8% vs 10.8% after cesarean). 1

Most Likely Etiologies at Day 14 Post-Cesarean

Endometritis/infection is the leading cause after cesarean section:

• Presents as a clinical diagnosis with nonspecific imaging findings of thickened heterogeneous endometrium with fluid, gas, and debris within the cavity. 2
• May be complicated by parametrial abscess or infected hematoma requiring drainage. 2, 1

Retained products of conception (RPOC):

• Occur in approximately 10.8% of secondary PPH cases after cesarean delivery. 1
• Difficult to differentiate from blood products even on multiphase CT. 2

Subinvolution of the placental bed:

• Represents failure of placental bed vessel obliteration leading to persistent bleeding. 2, 1

Vascular complications (less common but critical to identify):

• Uterine artery pseudoaneurysm can develop and present with delayed hemorrhage. 2, 1
• Bladder flap, subfascial, or perivaginal space hematomas—particularly those >5 cm—may become infected and bleed. 2, 1

Uterine scar dehiscence:

• A >5 cm bladder flap hematoma should raise suspicion for uterine dehiscence (disruption of endometrial and myometrial layers with intact serosal layer). 2
• Important pitfall: Do not misinterpret hypodense edema at the cesarean incision site as dehiscence in the first postpartum week, though by day 14 this distinction becomes more relevant. 2

Immediate Diagnostic Workup

First-line imaging: Transvaginal ultrasound with color Doppler 1, 3

Key sonographic findings to assess:

• Endometrial thickness >8–13 mm suggests RPOC, though this overlaps with normal postpartum appearance (normal thickened endometrial echo complex can be up to 2–2.5 cm in the early postpartum period). 2, 1
• Most specific finding for RPOC: Vascular echogenic endometrial mass demonstrating intralesional flow on color Doppler. 2, 1
• Color Doppler adds specificity and provides high negative predictive value by demonstrating intralesional vascularity. 1
• Presence of debris and gas is relatively common in the early postpartum period (20–25% of cases) and is nonspecific. 2

Advanced imaging when ultrasound is inconclusive or patient is hemodynamically unstable:

• CT abdomen/pelvis with IV contrast (in hemodynamically stable patients) can:

  • Localize bleeding sources and identify active extravasation. 2, 1
  • Detect vascular complications including pseudoaneurysm, bladder flap hematomas, subfascial hematomas, or perivaginal space hematomas. 2
  • Identify complications such as ovarian vein thrombosis, parametrial abscess, or infected hematoma. 2, 1

• Multiphasic CT angiography (non-contrast, arterial, portal venous phases):

  • Achieves approximately 97% accuracy for identifying active contrast extravasation. 2, 1
  • Active extravasation is seen in 41–74% of PPH cases on CTA. 2
  • Can identify and localize feeding arteries of arteriovenous malformations for treatment planning. 2

Critical Diagnostic Pitfalls

Do not rely solely on ultrasound to exclude pseudoaneurysm—serpiginous myometrial vessels on Doppler raise suspicion, but definitive confirmation requires CTA or angiography. 1

CTA can be falsely positive due to dilated tortuous hypertrophic uterine arteries mimicking extravasation, and falsely negative in atony due to slow intermittent hemorrhage. 2

On multiphase CT, RPOC may mimic blood products—correlation with clinical context and β-HCG levels (if elevated, consider gestational trophoblastic disease) is essential. 2, 1

Immediate Management Steps

Cause-specific treatment is essential 3:

• For RPOC: Surgical curettage is the definitive treatment. 3
• For endometritis: Antibiotics treat the infectious component but do not stop the hemorrhage itself—mechanical or surgical intervention may still be required. 3
• For vascular uterine anomalies/pseudoaneurysm: Arterial embolization is the preferred treatment. 2, 3
• For infected hematomas: Drainage may be required. 1

If bleeding is persistent or severe (>1000 mL):

• Initiate uterotonic therapy (oxytocin 5–10 IU IV/IM slowly, followed by maintenance infusion not exceeding 40 IU cumulative dose). 4
• If oxytocin fails, sulprostone should be administered within 30 minutes. 4
• Intrauterine balloon tamponade can be performed if medical management fails and before recourse to surgery or interventional radiology. 4

Fluid resuscitation and transfusion thresholds:

• Maintain hemoglobin >8 g/dL. 4
• Maintain fibrinogen ≥2 g/L during active hemorrhaging. 4
• Consider tranexamic acid 1 g (renewable once) if bleeding persists after sulprostone, though clinical value in obstetrics is not yet fully demonstrated. 4

Antibiotic prophylaxis:

• Should be re-dosed if blood loss exceeds 1,500 mL, regardless of initial cause. 3
• Manual uterine examination requires antibiotic prophylaxis. 4

Do not wait for laboratory confirmation of DIC before initiating massive transfusion protocol when blood loss exceeds 1,500 mL—immediate blood product administration in fixed ratios is recommended while addressing the underlying cause. 1