Gestational sac

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What is it the gestational sac, what is its function and what problems can it present? If you have these doubts, you came to the best place to solve them. Next we will solve the most frequent questions.

Gestational sac – Mothers And Babies – WebMediums

What is the gestational sac?

The gestational sac is the first visible structure in the ultrasound confirmation of pregnancy. Even before you can see the baby in formation or listen to your heart, it is already possible to visualize this membrane. It arises from the cell division that occurs right after the fertilization of the ovule, being the first protection for the development of the fetus.

From it the amniotic pouch will form, the placenta and other structures necessary to protect and nourish the baby until the moment of birth.

This primary structure is also an important indicator of the viability of pregnancy, providing important parameters for the diagnosis of possible interconnections that indicate the risk of spontaneous abortion.

When is the gestational bag formed?

Shortly after fertilization, there is the formation of the blastocyst, a set of cells that will be divided into two parts, one that will form the embryo and another the gestational sac and the other structures necessary for the growth of the baby during the 40 weeks of gestation.

The gestational sac appears between the fourth and fifth weeks of pregnancy, more or less when beta HCG, hormones of pregnancy, reaches the levels of 3 mUI / ml in blood. However, it is not visible until the sixth week of gestation.

When doing the transvaginal ultrasound in that phase of pregnancy, it will be possible to visualize the gestational sac and within it the vitellinic vesicle, a temporary structure responsible for feeding, bringing oxygen and blood to the embryo until the placenta is fully formed and mature to assume that function.

Until that stage, the embryo is microscopic and can only be seen after the fifth week, but it can often appear only in the seventh week.

Therefore, obstetricians prefer to wait until week 8 to request the first ultrasound evaluation of pregnancy, to have a more reliable prognosis on the development of pregnancy.

The gestational sac will support the development of the baby throughout the first trimester or week 12 of pregnancy.

What is measured in the gestational sac of the first ultrasound?

The gestational sac provides information important on the progress of a very delicate phase of gestation implantation and the start of fetal development. In the first ultrasound, the doctor will evaluate five aspects of the gestational pocket: implantation, size, contour, shape and content.

Bag implantation

It is evaluated if the gestational sac is implanted correctly in the uterus, if there is a low implantation or ectopic pregnancy, which usually occurs in the uterine tubes and rarely in the ovaries.

Bag size

The gestational pocket grows as the pregnancy progresses, following the development of the fetus. When you are a gestational minor, there is an increased risk of spontaneous abortion.

It is important to say that the size of the gestational sac should be evaluated along with other data, since a smaller bag than expected can indicate only a late ovulation, that is, that the ovum has been released and fertilized after the expected period within the menstrual cycle.

Rim and sack shape

A gestational sac with regular contour and shape is a sign of a promising gestation, with a risk of abortion less than 2%.

Gestational sac – Mothers And Babies – WebMediums

Content of the sack

The content of the gestational sac is also evaluated in the first ultrasound. In addition to the amniotic fluid and the vitellinic vesicle, from the seventh week it should be possible to see the embryo and hear its heartbeat.

When the embryo can not be visualized in this phase, it means that it has not developed and pregnancy is not feasible. These cases are known as a bag gestational anembryonic or anembryonic pregnancy.

What problems can occur with the gestational bag?

In addition to the problems of formation of the gestational sac, as irregular and asymmetrical shape and contour, low implantation in the uterus that generally make pregnancy impossible or the absence of an embryo, there is the detachment of the gestational pocket.

This occurs in healthy and well-formed gestational sacs, but who suffer a bruise: there is an accumulation of blood between the gestational sac and the wall of the uterus, which can lead to miscarriage.

The main causes of detachment of the gestational pocket they are the falls of the hormonal levels and the impacts on the gestation.

The detachment of a gestational sac it is a serious condition that requires medical attention. When the detachment is not greater than 50%, it is possible to revert the table with rest and use of medications prescribed by the obstetrician.

In more serious cases, the pregnancy can be hospitalized for the gynecologist to watch closely.

After approximately 15 days of medication and absolute rest, during this period the woman should not carry weight, have sex or make efforts that may worsen the clinical situation - it is necessary to repeat the ultrasound to check if the hematoma is cured.

Once the problem is solved, a good part of the pregnant women carry the pregnancy to the end without further interruptions.

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Saco gestacional
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