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

Background: Umbilical cord hemorrhage (UCH) is a rare but catastrophic obstetric emergency associated with nearly 50% fetal mortality, and its precise pathogenic mechanisms remain elusive in clinical practice. The pathophysiological cascade involves hemorrhagic expansion from ruptured umbilical vessels predominantly the umbilical vein which generates compressive forces on adjacent umbilical arteries within the constrained Wharton's jelly. This acute vascular compromise precipitates the sudden cessation of fetoplacental circulation, culminating in irreversible hypoxic-ischemic injury. Although the pathogenesis of UCH is multifactorial, the structural vulnerabilities of the umbilical vessels particularly elastic fiber deficiencies in the umbilical vein remain understudied. This case report describes a clinical outcome characterized by multifocal hemorrhagic lesions along the umbilical cord resulting from congenital elastic fiber deficiency in the umbilical vein during the late gestational stages, culminating in neonatal death despite emergent intervention.

Case report: A 31-year-old primigravida at 40⁺⁴ weeks gestation presented with abdominal pain and vaginal bleeding. Ultrasonography revealed cephalic presentation with the umbilical cord encircling the neck and torso once each. Following abrupt fetal bradycardia (80 bpm), fetal membrane was artificially ruptured, resulting in the release of 10 mL of yellowish-green amniotic fluid, which was classified as thick and contaminated to degree III. An emergency cesarean section was performed, delivering a male neonate (3,670 g). The Apgar scores were 10/2/0 at 1/5/10 min. Despite T-piece ventilation and chest compressions, resuscitation failed, resulting in neonatal death. Histopathological and macroscopic autopsy analyses revealed umbilical cord hemorrhage accompanied by umbilical vascular anomalies, specifically demonstrating a significant deficiency or complete absence of elastic fibers within the umbilical vein wall.

Conclusion: Umbilical vein dysplasia, characterized by elastic fiber deficiency, is an underrecognized yet critical contributor to perinatal hemorrhage-related mortality, particularly in cases of mechanical cord compression. We propose systematic elastin-specific histochemical evaluation as an essential component of postmortem protocols for unexplained intrauterine fetal demise. This evidence underscores the need to develop antenatal surveillance strategies targeting high-risk cord structural cord anomalies, specifically incorporating elastin-specific screening.