The fetal portal vein: normal blood flow development during the second half of human pregnancy

• DOI: 10.1002/uog.4054
• Publication Date: 2007-06-08T12:51:07Z
• Authors: J. Kessler; S. Rasmussen; T. Kiserud
• Keywords: Pulsatile flow; Ductus venosus

Abstract Objectives The umbilical vein is the major source of blood for fetal liver, but portal blood, which has not been measured directly in human fetuses, probably constitutes a physiologically important contribution. We aimed to establish method measuring flow and produce longitudinal reference ranges diameter, velocities volume during second half pregnancy. Methods After pilot project develop technique, 160 low‐risk pregnant women were recruited study that included ultrasound examinations at 4–5‐week intervals starting 20–22 weeks gestation. inner diameter (D) vessel was with perpendicular insonation angle, time‐averaged maximum velocity (TAMXV) weighted mean (VWMEAN) recorded an directed along long axis vessel. Portal calculated as: Q = π(D/2) 2 × h TAMXV (where profile parameter equals 0.5). normalized estimated weight based on birth‐weight percentiles. Results could be visualized 558/593 (94%) cases. Blood pulsatile. D doubled pregnancy (21–39 weeks), from 1.5 3.4 mm 8.4 14.9 cm/s, respectively. Correspondingly, increased 5 41 mL/min, 10 13 mL/min/kg when weight. Similar results achieved VWMEAN. Conclusion can standardized technique. It increases pregnancy, even weight, suggesting it increasing importance liver circulation. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.