Doppler blood flow velocimetry in the umbilical artery in uncomplicated pregnancy

Abstract

Objective: To determine the resistance index (RI) and pulsatility (PI) in the umbilical artery (UA) in prediction of abnormal fetal heart rate during labor and poor fetal outcome in term pregnancy. Material and Methods: The study included 148 patients at term in uncomplicated pregnancy. Daily evaluation of blood flow in the UA was performed and PI and RI were calculated. The last value before delivery was taken for the analysis. In turn predictive value of Doppler parameters has been determined in the prediction of abnormal FHR during labor and abnormal newborn condition. Evaluation included fetal CTG parameters and newborn status based on the V.Apgar scale and acid-base equilibrium in the umbilical cord blood. Then selected parameters, characterizing pregnancy and the newborn status, with abnormal Doppler results were compared. The prognostic value of Doppler indices was assessed for selected parameters determining the course of pregnancy and abnormal fetal heart rate. Results: A poor predictive value of UA PI and RI in the prediction of abnormal fetal heart rate during labor and poor fetal outcome was found. The RI in the UA presented the highest predictive value. Conclusion: RI in the UA shows higher predictive value than PI in the detection of abnormal fetal outcome and abnormal fetal heart rate in uncomplicated pregnancy at term. However, PI as well as RI in the UA have a low predictive value for the analyzed parameters.