Fatal Umbilical Cord Hemorrhage Triggering Neonatal Demise: Clinicopathological Insights from the Case Analysis

Introduction

The umbilical cord serves as the sole vital conduit for gas exchange, nutrient transfer, and waste elimination between the fetus and the placenta. In a full-term pregnancy, the umbilical cord measures 30–100 cm in length and 0.8–2.0 cm in diameter, comprising two umbilical arteries and one umbilical vein. Umbilical vessels are encased in a distinctive gelatinous tissue known as Wharton’s jelly. This tissue is colorless and translucent due to its high moisture content, which protects the umbilical vessels. Umbilical cord hematoma (UCH) is a rare cause of morbidity and mortality in neonates. This pathology may occur during pregnancy or, more frequently, during labor and is characterized by a hemorrhagic mass within the Wharton’s jelly of the umbilical cord, primarily localized near the fetal insertion of the umbilical cord. The hematoma may compress the vessels, specifically the two umbilical arteries and one umbilical vein, compromising maternal-fetal circulation and leading to an acute deficit in fetal blood supply. The umbilical vein exhibits a thinner wall, rendering it more vulnerable to compression and dilation.¹ Consequently, neonatal hypoxia occurs, a condition that can be lethal without prompt extraction of the fetus.

This report presents a case of multiple umbilical cord hemorrhage occurring at the end of term pregnancy, that resulted in neonatal fatalities. This case emphasizes the importance of assessment of underlying causes of umbilical cord hemorrhage and its relationship to causes of death in clinical diagnosis and death cause analysis.

Case Presentation

A 31-year-old primigravida presented with negative general and obstetric histories. The patient was admitted at 40 weeks and 4 days of gestation because of persistent lower abdominal pain lasting 3 h, accompanied by minimal vaginal bleeding. Color ultrasonography indicated that the fetus was in the cephalic position, with the umbilical cord wrapped around the neck and body in a single loop. An electronic fetal heart rate monitor indicated a reactive non-stress test with a fetal heart rate of 148 bpm. Forty minutes post-admission, the obstetrician auscultated the fetal heart rate at 80 bpm and promptly performed manual rupture of the amniotic membranes, leading to the release of 10 mL of yellowish-green amniotic fluid, which was classified as thick and contaminated to degree III. After 10 min, a caesarean section of the lower uterine segment was performed, resulting in the delivery of a live male infant in the right occiput posterior position, with a birth weight of 3670 g. The Apgar scores were 10 and 2 (one point each was awarded for heart rate and respiration) at 1 and 5 min post-birth, respectively. Positive pressure ventilation used a T-piece face mask for connection to an endotracheal tube, prompting the initiation of chest compressions. The Apgar score was 0 at 10 min post-birth. Resuscitative maneuvers proved unsuccessful, and clinical death was declared 1 h and 40 min after birth.

An autopsy was conducted on the third day after the neonate’s death. The neonate was male, weighing 3,600 g and 50 cm in length. The autopsy revealed pathological findings consistent with acute death characterized by cerebral edema and multiple organ congestion. The placenta weighed of 665 g and measured 17.5×15.5 ×2.2 cm. The umbilical cord was attached to the placenta at an eccentric location, with 32 cm of length remaining on the placenta, displaying slight spiral curling and subamniotic hemorrhage (Figure 1A). The umbilical cord at the base of the umbilicus in the fetus has been severed and tightly sutured on both sides, exhibiting a fusiform brownish alteration, measuring 6.4 cm in length and 3.3 cm in width at its widest point (Figure 1A). Continuous transverse sections demonstrated significant Wharton’s jelly hemorrhage, resulting in hematoma formation around the umbilical vein and two umbilical arteries, extending to the amniotic membrane (Figure 1B). The umbilical arteries exhibited notable thinning, which was difficult to observe visually due to hematoma compression. Microscopic analysis revealed that the umbilical vein lacked a muscular layer, which led to thinning and structural discontinuity (Figure 2A). Staining of the elastic fibers revealed a notable reduction or total absence of the purple internal elastic membrane in the umbilical vein as well as purple elastic fibers in the tunica media of the umbilical vein (Figure 2B). Considerable hemorrhage of the Wharton’s jelly surrounding the umbilical vein and arteries extending to the amniotic membrane resulted in significant compression of both umbilical arteries, as observed by microscopic analysis (Figure 3A and B).

Figure 1 Gross findings of the placenta and umbilical cord. (A) The umbilical cord attached to the placenta exhibited a slight spiral curling and subamniotic hemorrhage. The umbilical cord at the base of the umbilicus in the fetus has been severed and tightly sutured on both sides, exhibiting a fusiform brownish alteration. (B) The continuous transverse sections of the umbilical cord at the base of the umbilicus in the fetus demonstrated extensive hemorrhage of Wharton’s jelly, resulting in hematoma formation around the umbilical vein and the two umbilical arteries, which extended to the amniotic membrane.

Figure 2 Microscopic observations of the umbilical vein. (A) The umbilical vein lacked a muscular layer, leading to thinning and structural discontinuity as observed through HE staining. (B) A notable reduction or total absence of the purple internal elastic membrane in the umbilical vein, along with the purple elastic fibers in the tunica media of the umbilical vein by staining of elastic fibers. The scale bar, 200 µm.

Figure 3 Microscopic observations of the umbilical arteries. (A and B) HE staining demonstrates Wharton’s jelly hemorrhage compressing both umbilical arteries. The scale bar, 200 µm.

Discussion

From a clinical perspective, this case illustrates acute intrapartum fetal distress characterized by sudden fetal heart rate deceleration and meconium-stained amniotic fluid that progressed rapidly from initial clinical stability to acute fetal decompensation. Despite an initial Apgar score of 10 at 1 min, the neonate developed critically low scores (5 min: 2; 10 min: 0) and succumbed within 100 min post-delivery. Notably, this outcome underscores the limited sensitivity of Apgar scoring in assessing oxygenation and metabolism, as neonates may experience severe hypoxia and metabolic acidosis despite normal/near-normal Apgar assessments.² However, sustained arterial compression leads to rapid deoxygenation, evidenced by significant cord arterial pH decline with the bradycardia-to-delivery interval, at a rate of 0.009 per minute.³ Therefore, mandatory umbilical cord blood analysis (pH, blood gases, lactate) is essential for accurate evaluation of perinatal hypoxia-acidosis.⁴

The umbilical cord, comprising three vital blood vessels (typically two arteries and one vein), serves as a critical lifeline between the mother and fetus. Prenatal care includes detailed ultrasound examination of the umbilical cord, complemented by postnatal inspection of the placenta and umbilical cord, to identify and mitigate potential complications.⁵ Color ultrasonography serves as the gold standard for the prenatal diagnosis of umbilical cord entanglement. The sensitivity and specificity of prenatal ultrasound diagnosis of umbilical cord conditions are 80–96.8% and 87–96%, respectively.⁶ Color ultrasonography revealed umbilical cord entanglement in the fetus in this case. The prevalence of umbilical cord entanglement increases progressively with maternal gestational age, and it frequently leads to umbilical cord compression during delivery.² Umbilical cord entanglement refers to wrapping of the umbilical cord around the neck, limbs, or trunk of the fetus. Incidence rate of pregnancies involving entanglement around the neck is 14.7–33.9%.⁷ The effects on perinatal outcomes are comparable for umbilical cord entanglement around the neck and trunk but lower for entanglement around the limb.^8,9 Umbilical cord wrapping around the neck typically involves a single loop around the neck, which exerts minimal influence on safe length, and secondary hemorrhage of umbilical vessels is rare. In this case, at 40 weeks and 4 days of gestation, the umbilical cord exhibited complex entanglement around the fetal neck and torso, accompanied by significant cord hemorrhage. This presentation suggests associations with multiple entanglement sites and prolonged compression duration.

The postmortem identification of Wharton’s jelly hematoma, as described in this case, may lead to significant adverse outcomes, such as fetal distress, intrauterine death, and neonatal asphyxia, which can occur during or following delivery.⁹ Therefore, umbilical cord hemorrhage represents a critical obstetric emergency, necessitating meticulous evaluation of umbilical cord integrity to elucidate underlying etiologies. The rupture of the umbilical vein—a vessel anatomically predisposed to failure owing to its thin walls and high capacitance (transporting 50–60% of umbilical blood flow)—represents the primary pathomechanism initiating hemorrhagic cascades in the Wharton’s jelly.¹⁰ The extravasation of blood into the Wharton’s jelly, a proteoglycan-rich matrix normally resistant to compression, generates space-occupying hematomas that exert radial pressure on adjacent umbilical arteries.¹¹ Computational modeling indicates that a hematoma volume >5 cm³ creates intracordal pressures >30 mmHg, sufficient to collapse the low-pressure umbilical arterial system in late gestation.¹²

Wharton’s jelly hematomas are particularly insidious because of their dual roles as both mechanical disruptors and biochemical stressors. Hemoglobin degradation products, including free iron and heme, induce oxidative damage to adjacent cord structures, weakening vascular integrity.¹³ Additionally, thrombin released during clot formation activates protease-activated receptors on umbilical smooth muscle cells, triggering vasospasm and exacerbating circulatory stasis.¹⁴ These mechanisms together create a “no-reflow” phenomenon, where even hematoma resolution fails to restore adequate perfusion. Clinically, this manifests as sudden fetal heart rate decelerations (prolonged late decelerations with loss of variability) or atypical sinusoidal patterns, often misinterpreted as placental insufficiency rather than cord-specific pathology. Additionally, postmortem findings of fusiform brownish swelling in the umbilical arteries correlate with intimal necrosis and thrombosis, which are hallmarks of prolonged ischemia-reperfusion injury. Notably, the localization of hematomas near the fetal umbilicus, a region with reduced Wharton’s jelly thickness, amplifies vascular compression risks, as the cord’s diameter-to-jelly ratio here is lower than that in mid-cord segments.¹⁵

Owing to the absence of routine prenatal vascular elastography in this case, early detection of vascular wall abnormalities was not feasible, delaying diagnostic intervention. Additionally, as this is a case report, our findings cannot establish causal relationships or prevalence rates. Future multicenter studies with longitudinal prenatal monitoring are required to validate the association between elastic fiber loss and UCH.

Conclusion

The etiology of Wharton’s jelly hemorrhage remains multifactorial, with the following potential risk factors identified in this case: (1) umbilical cord anomalies, such as wrapping; and (2) umbilical vessel wall abnormalities, including congenital dysplasia of the muscle layer or elastic fibers. Therefore, acquiring clinical data regarding umbilical cord entanglement and utilizing elastic fiber staining to detect umbilical vessel wall abnormalities are essential for clinical diagnosis and death cause analysis.