What Is the Umbilical Vein?

Capillary blood vessels in the fetal placenta are collected into small to large venous channels. Finally it becomes a umbilical vein into the fetus through the umbilical cord, and enters the liver through the hilum.

Capillary blood vessels in the fetal placenta are collected into small to large venous channels. Finally it becomes a umbilical vein into the fetus through the umbilical cord, and enters the liver through the hilum.

Chinese name

Umbilical vein

Foreign name

umbilical veins

Make up

Superior mesenteric vein and splenic vein

During

Mammalian embryonic development

Genus

Superior mesenteric vein, splenic vein

Overview of the umbilical vein

The umbilical vein injects oxygen and nutrients from the mother's body (endometrium) into the fetal blood circulation through the fetal liver through the posterior vena cava to ensure fetal growth and development.

Umbilical vein (4 photos)

Umbilical vein fetal blood circulation:

Fetal blood circulation is the distribution of the cardiovascular system and the blood circulation pathways of the fetus before birth. Fetal nutrients, oxygen intake, and metabolic waste discharge must be exchanged through the umbilical cord to the placenta. Therefore, the blood circulation pathways are very different from those of adults. Corresponding changes will occur after birth.

Recycling route :

The nutrient-rich and high-oxygen blood from the placenta enters the fetus through the umbilical vein, enters the liver from the hilar portal, and then is divided into two ways. One part is mixed with the hepatic portal vein blood and flows into the lower cavity through the hepatic vein. Intravenous, another part into the inferior vena cava via a venous catheter. The blood from the umbilical vein and the blood returned from the lower part of the fetus are mixed into the right atrium in the inferior vena cava. Most of the mixed blood enters the left atrium through the oval hole, and then enters the aorta through the left ventricle. Department and Cardio Nutrition. Small femoral blood from the inferior vena cava in the right atrium mixes with blood from the head and upper vena cava into the right ventricle and then into the pulmonary artery. Because the fetus's lungs do not yet have breathing function, only a small amount of blood enters the lungs, and most of the blood enters the descending aorta through an arterial catheter. Most of the blood in the descending aorta returns to the placenta via the umbilical artery, and a small portion of the blood is supplied to the lower part of the body. The blood circulating in the fetus is a mixture of arterial blood and venous blood, but the ratio of the mixed components is different. The blood flowing into the upper limbs, head, heart and liver contains more oxygen and nutrients, while the blood flowing into the fetal lungs and lower body contains less oxygen and nutrients.

Cycle characteristics and main changes after birth:

(1) It has two umbilical arteries and one umbilical vein. When the fetus is born, the placental cycle is interrupted and the pulmonary cycle begins. Most of the umbilical arteries and veins fall off with the placenta and umbilical cord, and a section in the body gradually shrinks to form ligaments.

(2) There are oval holes in the left and right atrium septum to communicate the two atria. Blood can flow from the right atrium into the left atrium through the oval holes. After the fetus is born, the pressure of the left atrium greatly exceeds the pressure of the right atrium due to a sharp increase in the return of the pulmonary circulation, which causes the oval foramen to be closed and completely closed about 1 year after birth.

(3) There is an arterial catheter connection between the aorta and the pulmonary artery, and the venous blood from the superior vena cava that contains a lot of metabolic waste. After entering the pulmonary artery, most of it is injected into the descending aorta through the arterial catheter to ensure that important organs get fresh blood . Arterial ducts degenerate into ligaments after fetal birth.