Investigations for Umbilical Hematoma in a Newborn
Immediate Coagulation Assessment
The primary investigation for umbilical hematoma in a newborn is a comprehensive coagulation panel, including factor XIII levels, as bleeding from the umbilical stump or cord can indicate life-threatening coagulation factor deficiencies. 1
Essential Laboratory Tests
- Complete coagulation profile including PT, aPTT, fibrinogen, and platelet count should be obtained immediately 1
- Factor XIII assay is critical, as this deficiency specifically presents with delayed umbilical stump bleeding and may not be detected by routine coagulation tests 1
- Complete blood count to assess for anemia from blood loss into the hematoma or ongoing bleeding 2
- Blood type and cross-match should be prepared in case transfusion is needed 1
The case report by van der Linden et al. demonstrates that umbilical bleeding in a neonate with cephalic hematoma required fresh frozen plasma to stop bleeding, ultimately revealing factor XIII deficiency only after elaborate coagulation testing 1. This highlights that standard coagulation tests may miss critical factor deficiencies.
Clinical Assessment Parameters
Hemodynamic Monitoring
- Serial hemoglobin/hematocrit measurements to quantify blood loss, as umbilical cord hematomas can cause significant neonatal anemia (hemoglobin as low as 11.6 g/L has been reported) 2
- Vital signs monitoring for signs of hypovolemia or shock from acute blood loss 2
Neurological Evaluation
- Assessment for hypoxic-ischemic encephalopathy if there was prenatal cord compression or acute fetal distress, as umbilical cord hematomas can cause severe fetal compromise leading to neurological sequelae 2
Imaging Considerations
When Imaging May Be Indicated
- Ultrasound evaluation is appropriate if the hematoma extent is unclear or if there is concern for associated vascular malformation, though this is rarely the primary investigation 3, 4
- Doppler ultrasound can assess blood flow if vascular compromise is suspected 3
However, imaging is not the first-line investigation—laboratory assessment of coagulation takes priority 1.
Maternal and Placental Evaluation
Retrospective Assessment
- Maternal serum alpha-fetoprotein levels may be elevated if the hematoma developed prenatally, indicating fetomaternal hemorrhage 5
- Placental pathology examination should be performed to identify cord vessel rupture, inflammation (funisitis), or structural defects in vessel walls 2, 6
Subamniotic hematomas can be associated with fetomaternal hemorrhage and fetal growth restriction, even though located between chorion and amnion 5.
Common Pitfalls to Avoid
- Do not assume normal PT/aPTT excludes coagulation disorders—factor XIII deficiency requires specific testing and presents with normal routine coagulation studies 1
- Do not delay coagulation testing for imaging—the priority is identifying treatable bleeding disorders 1
- Consider infection as a predisposing factor—chorioamnionitis and funisitis can predispose to umbilical vessel rupture and hematoma formation 6
- Assess for cord abnormalities—defects in elastin and smooth muscle components of umbilical vessels may predispose to hematoma development 6