Fetal Ductus Venosus Pulsatility Index and Diameter during Second and Third Trimester of Gestation

Abstract

The ductus venosus is a small funnel shaped vessel found posterior to the fetal liver connecting the intra-abdominal umbilical vein and the inferior vena cava. It is one of the three physiological shunts in the fetus. The main objective of this study is to construct the reference table and normogram for fetal ductus venosus Pulsatility Index and diameter with gestational age. This was a prospective cross sectional study conducted during August 2011 to July 2012 taking 294 uncomplicated pregnancies using systemic random sampling method. Three measurements were made for ductus venosus diameter and Pulsatility Index in each fetus during period of fetal quiescence. The ductus venosus diameter at <20weeks, 20-25 weeks, 25-30 weeks, >30 weeks were 1.16, 1.31, 1.62, 1.81 and Pulsatility Index at <20weeks, 20-25 weeks, 25-30 weeks, >30 weeks were 0.41, 0.44, 0.41 and 0.41 respectively. The mean diameter of the ductus venosus was linear across gestational age. The Pulsatility Index shows a scattered distribution across the gestational age.