Late-term abortion associated with umbilical cord torsion in the mare: Case report

Torsion of the umbilical cord in the mare can be a cause of fetal death and abortion, commonly seen in mid-to late gestation. Length of the umbilicus is considered a contributing factor. Measured lengths of less than 84 cm (33 in) were considered normal in a study among Thoroughbred mares in 1 report. Increased lengths have been associated with excessive torsion and allantochorionic necrosis. The case presented conforms to these indications of vascular obstruction as the cause of fetal death, with visible twisting and excessive cord length after delivery of the dead foal.