Normative Values of Doppler Parameters of Blood Flow in the Fetal Hepatic Artery of Normal Karyotype Fetuses at 11-14 Weeks Gestation

The aim of the investigation was to develop normative (percentile) values of the peak systolic velocity (PSV) and the pulsatility index (PI) in the fetal hepatic artery in relation to the parietal-coccygeal length at 11-14 weeks gestation. Materials and Methods. PSV in the hepatic artery and its PI were estimated in 192 normal karyotype fetuses at 11-14 weeks of gestation. Results. The average values of PSV were 12.13 +/- 2.5 cm/s. They ranged up to 11.1 cm/s in those cases where the parietal-coccygeal length of the fetus was 45-52 mm and up to 14.6 cm/s when it was 62.1-79.0 mm. The upper limit of the norm was set as the 90th percentile. The average value of PI in the fetal hepatic artery was 1.98 +/- 0.12, standing at 1.9 in those cases where the parietal-coccygeal length was 45-52 mm and 1.7 where it was 62.1-79.0 mm. The lower limit of the norm was set as the 10th percentile. Conclusion. As the gestation period and, therefore, the parietal-coccygeal length of the fetus increase, the PSV in the fetal hepatic artery also increases, while the PI decreases. Such specific normative values of the blood flow indicators can be used in clinical practice to determine the risk groups for unfavorable perinatal outcomes.