Yolk sac

The first fruit-feeding organ is the yolk sac. The norm or, most accurately, the optimal time of appearance is 15-16 days of development of the fetal egg. This substance is formed from an endoblastic vesicle, which is a derivative of the embryoblast. This small formation, which is in direct contact with a fertilized egg, is unique in its composition and functions.

An interesting fact is that it is the yolk sac that gives rise to the formation of blood cells and a fine capillary network. Already from 18-20 days of development of the fetal egg in it you can find a small blood mesh.

Thus, this body is one of the most important for the future baby. After all, until the placenta with a dense blood network is formed, all the nutrients the embryo will receive from the yolk formation.

Already by the 30th day of development, the yolk sac conveys the primary sex cells to the embryo - the baby's sexual system begins to form. Many people think that it is at this time that they decide who will be born, a boy or a girl. However, young parents need to know that the sex of the baby is decided at the time of fertilization, and at all other stages of development only the organs are formed, in accordance with genetic information.

Numerous functions of the primary feeding organ do not end there. To all other things, before the 6th week of the development of the embryo, the yolk sac also performs the function of the liver, or, more precisely, synthesizes proteins: alpha-fetoprotein, transferrin, alpha2-microglobulin.

It must be remembered that this organ is also a kind of envelope of the fetus, until the moment when its immune system can not itself fight against possible pathogenic microorganisms. The fact is that the primary organ of the fetus can independently produce macrophages in the fight against infection. Thus, it protects the fertilized egg from negative impact from the outside.

This system of protection and nutrition of the fetus does not work very long, by the end of the first trimester the yolk sac degenerates and turns into a small peri-pouche formation. By this time, all of its functions are assumed by the formed placenta and other organs of the fetus.

It must be said that if, for some reason, the yolk formation begins to regress before the placenta or other important formations are formed, miscarriage or intrauterine fetal death is possible . That is why there are certain time intervals when it is necessary to undergo ultrasound.

How can you find a yolk sac and determine its functionality?

Women who are preparing for the birth of a baby, probably already read in the literature that with ultrasound, the yolk sac can be seen only from the 6th week of fetal development, and in some cases a little later. This may be due to the location of the fetal egg or the sensitivity of the equipment.

If you are told by ultrasound that the yolk sac is not visualized, you do not need to panic right away. Listen to the doctor to the end. Surely he will explain everything to you.

There are many variants of the pathology of pregnancy, in which the bag is reduced too soon, or it is not sufficiently developed. A woman should understand that even if it is possible to maintain such a pregnancy, the likelihood of developing malformations in such a baby is doubled.

It must be said that monitoring the development of yolk education before the 12th week of pregnancy can tell how the development of the fetus will proceed and with what complications doctors and parents may face.

There is such a thing as "frozen pregnancy" - this is the pathology of the yolk sac, in which it is small and non-functional. The fruit reaches a certain stage of development, and for further growth of nutrients is no longer enough. In such a situation, it is necessary to perform cleaning of the uterine cavity in conjunction with hormonal therapy.