- Rare, usually occurring in
late pregnancy and labor.
- Incidence - 1/5500 deliveries
in Dippel's`series.
- Usually due to rupture of the
umbilical vein secondary to:
- mechanical trauma
between fetal and maternal tissues.
- traction on a short
cord.
- loops of cord around
the fetus.
- congenital weakness of
the vessel wall.
- iatrogenic (post
percutaneous umbilical cord sampling).
- High rate of perinatal loss
(47% in Dippel's series).
- Fetal death in utero
(approaches 50%) (2):
- one mechanism is
compression of the umbilical vessels by the increased pressure of blood
filling the Wharton's jelly in the substance of the cord.
- Sonolucent septated mass
adjacent to the fetal abdomen (2).
- Can occur anywhere along the
length of the cord but is usually located at the umbilical end.
- Most contain only small
volumes of blood.
- Ratten GJ. Spontaneous hematoma
of the umbilical cord. Aust NZ J Obstet Gynecol 1969;9:125.