Oxygenated blood from the placenta reaches the fetal hea In utero :
Oxygenated blood passes from the placenta to the fetus the umbilical vein which passes beneath the anterior abdominal wall and distributes blood to the liver and the ductus venosus to the inferior vena cava which then enters the right atrium. Reference: Williams textbook of Obstetrics,4th edition page 135
Umbilical aeries
Umbilical vein
Ductus venosus
Ductus aeriosus
General obstetrics