What is the fetal circulatory route? The fetal circulation system has two cardiac shunts. The right and the left atria are connected by the foramen ovale. And the truncus pulmonalis and the arota are connected via the ductus arteriosus. By having the flow of blood go through these pathways, the blood from the placenta, rich in nutrients, gets there via the umbilical vein in the liver. The umbilical vein transports nutrients from the placenta, which is channeled through capillaries in the liver. The pressure in the umbilical veins increases, which causes more nutrients to be sent to the inferior vena cava via the ductus venosus, is caused by periodic contractions of the uterus. The relaxation of the uterine walls leads to a decrease in the umbilical
