How does the fetal circulatory system work? During pregnancy,
the fetal circulatory system works differently than after birth:
- The fetus is connected by the umbilical cord to the placenta,
the organ that develops and implants in the mother's uterus
during pregnancy. - Through the blood vessels in the umbilical
cord, the fetus receives all the necessary nutrition, oxygen,
and life support from the mother through the placenta. - Waste
products and carbon dioxide from the fetus are sent back through
the umbilical cord and placenta to the mother's circulation to
be eliminated. Blood from the mother enters the fetus through
the vein in the umbilical cord. It goes to the liver and splits
into three branches. The blood then reaches the inferior vena
cava, a major vein connected to the heart. Inside the fetal
heart: - Blood enters the right atrium, the chamber on the upper
right side of the heart. Most of the blood flows to the left
side through a special fetal opening between the left and right
atria, called the f