How long does it take to detect the yolk sac during pregnancy?

I wonder if you have seen the term yolk sac when you go to the hospital for a checkup? Do you know what the yolk sac is? What is the function of the yolk sac? Let's discuss it together below. Do you also know when the yolk sac appears? How long does it take to detect the yolk sac during pregnancy?

How long does it take to detect the yolk sac during pregnancy?

The yolk nest is a membranous sac rich in blood vessels, which contains the yolk and is located on the ventral side of the embryo. The part that communicates with the midgut of the embryo is also called the yolk sac stalk. The yolk membrane has the function of storing, decomposing, digesting and transporting nutrients, and different types of animals have different yolk membranes. The yolk membrane will gradually shrink as the fetus grows until it becomes a part of the colon and will no longer be visible after about 12 weeks of pregnancy.

The earliest origin of somatic cells is also the yolk membrane. In the early stages of a woman's pregnancy, the first thing that can be observed by ultrasound is the yolk nest in the gestational sac, which is an important transport system between the embryo and the pregnant mother. Generally speaking, what pregnant mothers are most concerned about is the time when the yolk nest appears. So, in which week will the yolk nest appear during pregnancy? This is a question that many pregnant mothers are very concerned about. Next, the editor will explain it to everyone.

Before the test tube embryo is perfected, the yolk nest transports nutrients to the ovum and is the shipping system between the test tube embryo and the pregnant mother. It has functions such as nutrition, hematopoiesis, metabolism and immunology. During the fifth week of pregnancy, the yolk nest separates from the archenteron and gradually decays. Until the 7th week, it becomes a small sac with a diameter of less than 5mm, existing on the surface of the test tube embryo. This is also a situation caused by the repetitive system. Generally speaking, the gestational sac and yolk nest can be detected on the 35th day of pregnancy. The embryo bud is produced in 40-50 days. The embryonic heart appears in 50-60 days. If the normal menstrual period is delayed, it may be that the ovulation period is late, which means that the appearance of the yolk nest, embryonic bud and embryonic heart may also be delayed. If calculated based on a 28-day menstrual cycle, ovulation usually occurs on the 14th day of the menstrual period. If calculated based on 35 days, then ovulation occurs around the 20th day of the menstrual period.

The effect of yolk sac

For women who are pregnant for the first time, during pregnancy, women will pay special attention to the changes in their bodies. Yolk nest is a term that is often seen in the medical examination list shortly after pregnancy. Many doctors have also mentioned the importance of yolk nest. It is an important transportation system between the test tube embryo and the pregnant mother. So what is the function of yolk nest? Let's learn more about the functions of yolk nest with the editor below.

The yolk sac is formed when the test tube embryo develops wrinkles and the archenteron is divided into two parts: the archenteron inside the embryo and the yolk sac outside the embryo. There is a lot of yolk in the yolk sac, and the extraembryonic endoderm and extraembryonic mesoderm form the wall of the yolk nest. Generally speaking, seeing the yolk sac means that the test tube embryo is normal. But then the yolk nest will gradually disappear.

It is normal for the gestational sac to have a yolk nest. On the contrary, the absence of a yolk nest may lead to pregnancy termination. For example, having a yolk nest is equivalent to a house waiting for someone to live in it. It is also mentioned above that the yolk nest appears about 35 days after pregnancy, and the embryonic heart is 1-2 weeks after the appearance of the yolk nest. All are observed through B-ultrasound. Under normal circumstances, ordinary instruments can also be used for examination.