Risk factors for spontaneous hematoma of the umbilical cord: A case-control study.

BACKGROUND

Spontaneous hematomas of the umbilical cord are rare and often fatal to the fetus. Little is known about their mechanism or their risk factors. In view of their rarity, the series are limited. No comparative study enabling the identification of factors associated with these hematomas has been published.

MATERIAL AND

METHODS

This retrospective case-control study of 13 spontaneous histologically confirmed hematomas of the umbilical cord over a consecutive 16-year period compared the characteristics of the case mothers and fetuses to those of a group of 39 control mothers who gave birth the same day as the case mothers.

RESULTS

In utero death was high in the case group (46.2% vs 0.0%, P < 0.001). Third-trimester oligohydramnios (30.8 vs 2.6%, OR = 16.9, P = 0.01), second-trimester amniocentesis (33.3 vs 5.1%, OR = 9.3, P = 0.02), and a reduction in fetal movements as perceived by the mother (35.7 vs 7.7%, P = 0.02) were significantly associated with spontaneous umbilical cord hematomas.

CONCLUSION

Third-trimester oligohydramnios and second-trimester amniocentesis appear to be associated with the occurrence of a spontaneous hematoma of the umbilical cord.