Relationship between fetal heart, fetal bud and yolk sac

After becoming pregnant, every pregnant mother hopes to give birth to a healthy baby smoothly. However, confirming pregnancy cannot determine everything. The yolk sac needs to be tested, and the fetal heart rate and fetal bud need to be understood. These professional terms will definitely make some pregnant mothers dizzy. In fact, the fetal heart rate, fetal bud and yolk sac are closely related. So, what is the relationship between the fetal heartbeat, fetal bud and yolk sac? Let’s take a look below.

Generally speaking, the development of the germ is behind the yolk sac, that is, the gestational sac begins to develop, the yolk sac gradually develops, and the embryo develops into the germ. After that, the embryo has fetal heart development, which is a developmental process. After each organ is gradually formed, it is called the embryo before the 8th week of gestation. By the fourth week, the blastocyst has implanted firmly in the uterus.

At the same time, almost prototypes of the fetal nervous system and blood circulation organs appeared. Since then, the liver has developed rapidly and has not yet produced the prototypes of the eyes and nose, but the prototypes of the mouth and chin can be seen. Generally, the fetal bud can be seen on ultrasound at 6-7 weeks of pregnancy. Due to the development of the embryo, it takes 30-40 days for the fetal capsule to form, 40-50 days for the fetal bud to form, and 50-60 days for the fetal heart to form, so usually B- should be completed within about 60 days.

What is fetal heartbeat?

The fetal heart develops during the first two weeks of the fertilized egg, called the gestational egg. After the various organs are gradually formed, before the 8th week of pregnancy, it is called an embryo. Due to the development of the embryo and the formation of the fetal capsule

The fetal heart rate is the heartbeat of the fetus. Usually, the fetal heart rate can be heard in the abdomen with an ordinary stethoscope between 17 and 20 weeks. Fetal heart rate 120-160 beats/minute, sometimes faster, less regular, and more regular toward the end of pregnancy. Sometimes there will be brief pauses, or up to 180 beats per minute, this is normal. However, if this phenomenon occurs frequently and lasts for a long time, consult a doctor immediately.

What is the yolk sac?

After yolk sac embryogenesis, the gastrula clearly divides into the embryo and the extraembryonic yolk sac, which contains a large amount of yolk. The yolk sac wall is composed of extraembryonic endoderm and extraembryonic mesoderm.

The occurrence of the yolk sac in human embryos is also one of the recurring phylogenetic phenomena. In the third week, the extraembryonic mesoderm of the human yolk sac forms many blood islands, which is where the embryo first forms blood vessels and blood cells. It is the hematopoietic site of the early embryo. Yolk sac movements and veins will be involved in the initiation of mesenteric artery and hepatic portal vein formation.

Since primordial germ cells first appear on the yolk sac wall, the yolk sac is the original origin of germ cells. Similar to humans, yolk sacs may also occur in other vertebrates and cephalopods, which are mollusks.