RUPTURE OF THE UMBILICAL CORD VESSELS

ETIOLOGY

• Non-traumatic, non-inflammatory spontaneous rupture of the umbilical cord vessels prior to delivery has been reported in 1:5500 births (1).
• Majority are due to rupture of the umbilical vein (67%).
• 13% are due to rupture of the umbilical artery.
• In 20% of cases all vessels appear intact and the source of rupture is not identified (3).
• Ruptures are usually secondary to:
• Varices (usually rupture through the amniotic sheath and hemorrhage into the amniotic fluid with fetal exsanguination) (4,5).
• Aneurysms.
• Focal thinning of the vessel wall due to splitting of the elastic membranes (6).
• Hematomas of the cord due to hemorrhage into Wharton's jelly causes compression of the other vessels and possible anoxia, but does not generally cause rupture (2).

MORTALITY RATE

• High (± 45%) (1,7).

REFERENCES

1. Dippel AL. Hematomas of the umbilical cord. Surg Gynecol Obstet 1940;70:51.
2. Summerville JW, Powar JS, Ueland K. Umbilical cord hematoma resulting in intrauterine demise. L Reprod Med 1987;32:213.
3. Clausen I. Umbilical cord anomalies and antenatal fetal deaths. Obstetrical and Gynecological Survey 1989;44(12):841-845.
4. Adair FL, McDonald RE. Varix of the umbilical cord with report of a case. Am J Obstet Gynecol 1929;17:836.
5. Swanberg H, Wiqvist N. Rupture of the umbilical cord during pregnancy. Acta Obstet Gynecol Scand 1951;30:323.
6. Clare NM, Hayashi R, Khodr G. Intrauterine death from umbilical cord hematoma. Arch Pathol Lab Med 1979;103:46.
7. Ruvinsky ED, Wiley TL, Morrison JC, Blake P. In utero diagnosis of umbilical cord hematoma by ultrasonography. Am J Obstet Gynecol 1981;140:833.