Correlation between umbilical cord torsion and Doppler parameters of umbilical artery: a single-center retrospective case-control study

Objective:To explore the correlation between umbilical cord torsion and the changes of umbilical artery Doppler parameters, to provide valuable information for prenatal ultrasound screening of umbilical cord torsion, and to explore the possible mechanism of umbilical artery Doppler parameters changes during umbilical cord torsion. Method:The subjects were 962 pregnant women who were discharged from our hospital from January 2015 to November 2021 and were eligible for inclusion (415 in the case group and 547 in the control group). The measurement data of umbilical artery Doppler parameters (PSV, S/D, RI, PI) were collected from 21 to 40 weeks of gestation, and the differences among the above parameters were statistically analyzed. Results:The peak systolic velocity (PSV) of umbilical artery is positively correlated with gestational age, while the Doppler resistance parameters (S/D, RI, PI) of umbilical artery are negatively correlated with gestational age. The mean values of umbilical artery Doppler parameters (PSV, S/D, RI, PI) in the case group were significantly lower than those in the control group of the same pregnancy age (P < 0.05). Conclusion: The decrease of Doppler parameters of umbilical artery in late pregnancy is significantly related to umbilical cord torsion, which may be a clue for prenatal ultrasound screening of umbilical cord torsion. The Doppler parameters of umbilical artery during umbilical cord torsion are consistent with the basic principle of Doppler parameters change after vascular stenosis in other parts of the human body. It is necessary to conduct multicenter prospective study in the future.