Umbilical artery thrombosis risk factors and perinatal outcomes.

PURPOSE: The purpose of this study was to investigate the risk factors for umbilical artery thrombosis (UAT) and the relationship between umbilical artery thrombosis and perinatal outcomes.

METHODS

This was a retrospective study that enrolled singleton pregnant women who were diagnosed with umbilical artery thrombosis. The control group recruited pregnant woman with three umbilical vessels or those with isolated single umbilical artery (iSUA) who were matched with umbilical artery thrombosis group. The risk factors and perinatal outcomes were compared between the groups.

RESULTS

Preconception BMI (OR [95%CI]: 1.212 [1.038-1.416]), abnormal umbilical cord insertion (OR [95%CI]: 16.695 [1.333-209.177]) and thrombophilia (OR [95%CI]: 15.840 [1.112-223.699]) were statistically significant risk factors for umbilical artery thrombosis. An elongated prothrombin time (OR [95%CI]: 2.069[1.091-3.924]) was strongly associated with the occurrence of UAT. The risks of cesarean delivery, preterm birth, fetal growth restriction, neonatal asphyxia, and intraamniotic infection were higher in pregnancies with UAT than in pregnancies with three umbilical vessels or isolated single umbilical artery (P<0.05). Additionally, the incidence of thrombophilia was higher in pregnant women with umbilical artery thrombosis than those with isolated single umbilical artery (P = 0.032). Abnormal umbilical cord insertion was also found to be associated with an elevated risk of iSUA (OR [95%CI]: 15.043[1.750-129.334]).

CONCLUSIONS

Abnormal umbilical cord insertion was the risk factor for both umbilical artery thrombosis and isolated single umbilical artery. The pregnancies with umbilical artery thrombosis had a higher risk of the adverse perinatal outcomes.