What is the central incomplete presentation of the chorion. Chorion presentation

The term "chorion" is used by gynecologists to refer to the placenta in the first trimester of pregnancy. In many patients in the early stages, the entry “chorion previa” appears in the card. Like everything unknown, this definition, coupled with the word diagnosis, can seriously scare the expectant mother.

Let's try to explain in an accessible way what chorion previa is. This diagnosis means the incorrect location of the placenta. When instead of attaching to the body of the uterus, it can capture the lower uterine segment.

Sometimes there is a partial or complete overlap of the internal pharynx of the cervical canal leading from the uterus. This diagnosis is most relevant for the first trimester of pregnancy. Basically, as the fetus develops, the chorion rises. But there are times when this does not happen.

Types of chorion presentation

At low presentation chorion observed attachment of the fetal egg a couple of centimeters below the cervix. It occurs in only 5% of pregnant women. Such a diagnosis can only be made during an ultrasound. Low attachment is most common in the first two trimesters. In 90% of cases, the chorion safely rises to the desired position as the fetus grows. This is due to the fact that the tissues of the uterus are pulled up and pull the placenta along with them. Thus, everything is done without medical treatment.

There are presentations on the back or front uterus. The first option is the most common and is considered the norm. In this case, the placenta can also pass to the side walls of the uterus. Nothing wrong with that. In the case of the chorion along the anterior wall, there is also no cause for concern. In this variant, placental migration occurs even faster.

It happens that the placenta has not risen, but the overlap of the internal os is not observed. In this case, the pregnant woman is recommended complete rest and constant monitoring by a gynecologist.

At partial presentation the placenta can cover up to two-thirds of the cervix. A variation of this type is called marginal presentation , in which the overlap of the opening of the uterus does not exceed one third. These options are worse, but also not hopeless. Although the risk of miscarriage is increased and bleeding may occur, inpatient treatment is not used.

The most dangerous is the complete or central placenta previa . In this case, there is a complete overlap of the internal pharynx of the cervical canal. With this form of presentation, starting from 4 months, hospitalization is indicated. Although outwardly everything may be fine, there is a huge risk of heavy bleeding. They can develop for no apparent reason, even in a state of complete rest. Therefore, in order not to risk the life of a pregnant woman, doctors observe her in a hospital.

However, in any case, you should not panic. Although a caesarean section is indicated for full presentation, there is a real chance of maintaining the pregnancy. A favorable outcome is observed in 95% of cases.

The main causes of chorion presentation

The main reason for this violation is pathology of the inner walls of the uterus , due to which the embryo cannot attach to them. Often, these pathologies occur due to abortion or due to sexually transmitted infections. Presentation can also develop when the uterus is deformed, which occurs as a result of myomectomy.

Women suffering severe forms of diseases heart, kidney, or liver are at increased risk. This is due to congestion in the uterine cavity. Chorionic presentation often suffer second-born women especially over 35 years of age.

This deviation may be related to pathology of the ovum , as a result of which it is impossible to fully attach the latter. It also happens that the placenta is attached too tightly and cannot separate on its own during childbirth.

It will be appropriate to note that chorion previa, excluding the central variant, can only be positively diagnosed at the end of pregnancy, since the position of the placenta can always change.

Consequences of chorion presentation

The most common complication of presentation, as well as a symptom, is bleeding . Its character depends on the degree of presentation. During full presentation, bleeding is observed already at 2-3 months. The lateral form involves bleeding after 6 months and during childbirth. The intensity of hemorrhages is also determined by the degree of presentation. It is noticed that 20% of cases they occur during the second trimester.

Bloody discharge in this pathology is of a special nature.

The advantage is that the outpouring always occurs outside, and avoids the formation of hematomas between the uterus and the chorion. However, this does not reduce the danger to the expectant mother and child.

The distinguishing feature of these bleedings is suddenness. At the same time, the pregnant woman does not experience any pain or discomfort. This allows you not to confuse them with spontaneous abortion, which is always accompanied by painful cramps.

Having appeared once, bleeding tends to be repeated at different intervals. It is impossible to predict its intensity and abundance.

The main threat of placenta previa is miscarriage . The tone of the uterus, pulling pain in the abdomen and lower back can signal danger. Often a constant accompanying symptom is

Many women before the onset of pregnancy did not know about the existence of the chorion, about its significance, and even more so about the presentation of the chorion. So, first, let's find out what a chorion is. Chorion is the outer embryonic membrane, which, having passed the early stage of the individual development of the fetus, turns into the placenta, which is fixed by a “large sucker” with the help of numerous villi into the inner membrane of the uterus.

Note that the villous membrane - the chorion - performs several vital functions for the fetus in the early stages of pregnancy:

• respiratory - ensures the removal of carbon dioxide, and the supply of oxygen from the mother to the fetus;
• trophic - ensures the delivery of nutrients from the mother;
• excretory - with the help of the chorion, metabolic products are excreted; protective - protects the fetus from external influences.

What does chorion previa mean?

In order to understand why the low location of the chorion is dangerous, let's define what presentation is. So, chorion presentation is a pathology of pregnancy, in which it is located in the lower part of the uterus. In this case, the chorion partially or completely overlaps the internal pharynx.

Chorionic presentation - causes

The causes of chorion previa have not been elucidated, but some factors that affect chorion previa are still known: uterine fibroids, abnormal development of the uterus, postoperative scars on the uterus, chronic inflammation of the uterus, chorion previa in previous pregnancies, frequent abortions. Chorionic presentation along the anterior wall or presentation can also occur due to polyps or multiple fibroids. Therefore, frequent visits to the gynecologist for preventive examinations and a healthy lifestyle will help to avoid problems associated with possible presentation and its consequences during pregnancy.

Why is chorion previa dangerous?

Such a classification of chorion presentation is accepted. Complete presentation of the chorion is dangerous by the complete overlap of the internal os of the cervix. It is also called the central presentation of the chorion. Such an arrangement is dangerous with severe bleeding due to placental abruption, and hypoxia is dangerous for the child at this time, due to which he can die in a matter of minutes.

Partial presentation of the chorion means that only part of the internal os is blocked. Low chorion presentation means that the chorion does not overlap the internal os, but is located at a distance of less than 3 cm from it.

During pregnancy, the placenta migrates all the time, so even a complete placenta previa for childbirth can become normal. Chorionic presentation is an indication for caesarean section, natural childbirth in this case is excluded.

Chorionic presentation - treatment

Treatment of presentation as such does not exist, the main thing is to adhere to preventive measures. The best prevention is a healthy lifestyle and regular visits to the doctor, identifying and controlling the appearance of fibroids and polyps before the onset of pregnancy. If, nevertheless, chorionic villus presentation was detected during pregnancy, it is necessary to stop sexual relations, reduce physical activity to a minimum, eliminate stressful situations and limit mental stress, take a complex and drugs to reduce uterine tone, as well as iron preparations to prevent anemia.

Regular ultrasound examinations will help to qualitatively control the current situation, and in the third trimester the placenta may safely migrate and gain a foothold in a safe place, which will lead to natural childbirth.

Chorionic previa (placenta) is an incorrect location of the placenta, when instead of the body of the uterus, it captures partially or completely the lower uterine segment. Chorion is a synonym for the placenta in the early stages of development. By the end of pregnancy, in most patients, the chorion rises, but there are exceptions. If the localization of the chorion is posterior, then it will rise more slowly, if it is anterior, then faster.

Causes of the disease

The exact and reliable causes of this disease are unknown, but there are a number of factors contributing to the development of this disease. In particular, chorionic presentation may develop due to:

• after a caesarean section;
• Scar after myomectomy;
• A large number of births in the patient;
• Age over 35 years;
• Chorion previa during previous births;
• chronic;
• Tumor of the uterus (myoma);
• Anomalies and pathologies during the development of the organ;
• Smoking.

In addition, we can say that chorion previa is quite common in early pregnancy, statistically up to 30% of cases.

Symptoms of the disease

The main symptom of the disease is the appearance of bleeding, which appears due to the fact that the placenta is not capable of stretching, therefore, when the uterus is stretched, it exfoliates and bleeds. Bleeding can appear spontaneously, then disappearing, then reappearing, while pain disappears. The low location of the chorion contributes to heavy bleeding. In addition, factors such as exercise, vaginal examination, sexual intercourse, hot baths, saunas, and constipation can trigger bleeding.

Complications that can cause chorion previa

The main complication that this disease gives is an unplanned abortion or premature birth. With this disease, the child develops normally, but characteristic hypotension is recorded in patients, so even a small blood loss leads to anemia. If the bleeding began spontaneously, then sometimes you have to take the last measure in order to save the life of the mother and baby.

Diagnosis of the disease

Diagnosis of presentation usually does not cause difficulties in a patient normally observed in a hospital. This disease is perfectly diagnosed during a routine ultrasound examination. pregnant women are not recommended.

If the patient did not undergo an ultrasound examination, then this disease can be recognized by which are not accompanied by pain, as well as by the high standing of the uterine fundus.

Treatment of the disease

First of all, it must be said that all drugs for this pathology are absolutely useless, because they cannot affect the location of the chorion in any way. If suspicious symptoms appear and the disease is diagnosed, it is necessary to completely exclude any physical activity, as well as completely exclude sexual contact. In addition, the patient needs constant supervision of a specialist, so she is hospitalized in the hospital.

In the event that there is no constant bleeding, the patient may well be at home, while more often resting in the fresh air and eating right, choosing a diet to prevent constipation. It should be noted that this is especially important, because with this pathology, any laxatives are contraindicated.

If the patient has a complete presentation of the chorion, then natural childbirth is contraindicated for her and it is required. In natural childbirth, there is a high risk, as a result of which there will be a large blood loss, which will threaten the health of both the mother and the child.

When Preposition Occurs

Symptoms of improper location of the chorion

Possible Complications

Treatment of chorion previa

With such a diagnosis as marginal presentation of the chorion, according to statistics, up to 45% of pregnant women face in the early stages of bearing a baby. Is it worth it to be afraid of such a medical verdict, and what to do, will be discussed in this article.

What it is?

Chorion is a temporary body that performs the functions of a pharmacist. It is formed from the moment of implantation of the fetal egg from the fallopian tube, where the meeting of the egg and sperm took place, into the uterine cavity. As soon as the blastocyst (a fertilized egg turns into it by the 8-9th day after ovulation) reaches the uterine cavity, it seeks to gain a foothold in it. This process is called implantation.

At the site of attachment of the blastocyst membrane, special enzymes are secreted that make the mucous membranes of the uterus more pliable and allow the fetal egg to "grow". At the site of attachment, a chorion is formed. It is necessary to nourish the fetal egg with useful substances from the mother's blood. A placenta appears in its place a little later. But until 12-13 weeks we are talking about the chorion, since the placenta is still being formed and does not function.

If the implantation is successful, the fetal egg is fixed in the fundus of the uterus (this is its upper part). If, for some pathological reasons, the blastocyst failed to implant in the upper or middle part of the uterus, it can descend into the lower uterine segment. And then the chorion will form low.

Chorion presentation is its location relative to the cervical canal - a thin passage inside the cervix that connects the uterine cavity and the vagina. There is no question of presentation only if the chorion has formed in the region of the fundus of the uterus or in its middle part (in the body of the uterus).

If the chorion is located low, there are several types of presentation.

Classification

Depending on the degree of overlap of the cervical canal, through which the fetus then has to pass during childbirth, distinguish the types of pathology.

• Marginal presentation of the chorion- the chorion is located low, its edge slightly touches the area of ​​the cervical canal with one edge. Such a presentation is considered the most favorable, in terms of prognosis, for further pregnancy and childbirth.
• Incomplete presentation- the chorion is located low and covers the entrance to the cervical canal by about two-thirds. The prognosis is less optimistic, since this position of the chorion in the uterus increases the likelihood of miscarriage or bleeding due to detachment of the chorion.
• Full presentation- the chorion has formed low and completely closes the entrance to the cervical canal. This is a rather dangerous pathology, the prognosis for which is very unfavorable.

Any presentation of the chorion, but especially complete and incomplete, creates a threat of miscarriage, detachment of the chorion. In its place, a placenta will form, a network of blood vessels will develop, and it is dangerous if the vessels grow in the lower part of the uterus, which, according to the laws of nature, should open up and release the baby out when the due date comes.

Often, chorion previa can go into another pathological condition - placenta previa, and then independent childbirth in a natural way is likely to be contraindicated. The woman will have a caesarean section. It will also not be easy to carry the baby to the due date, since the placenta, located low and adjacent to the exit from the uterus, will create a risk of spontaneous bleeding at any time.

A child with presentation will receive less oxygen and nutrients, and this is fraught with malnutrition and hypoxia.

Causes and symptoms

The main reason for marginal presentation is the internal prerequisites that prevented the fetal egg from implanting normally and into a more suitable uterine fundus. These prerequisites include violations of the state of the endometrium of the uterus. It is usually observed in women who have had several abortions or have undergone diagnostic curettage.

Miscarriages, missed pregnancies in history also increase the likelihood of misplacement of the ovum. An obstacle to full implantation may be a scar or several scars on the uterus from previous operations or caesarean section.

Women who have given birth a lot cannot boast of strong and elastic muscle tissues of the reproductive organ, they also increase the likelihood that a subsequent pregnancy may occur against the background of low placentation.

The presence of fibroids, fibromas and other formations in the upper part of the uterus also creates obstacles for the attachment of the blastocyst, and it is forced to descend in search of a "shelter" in the lower uterine segment. The cause may also be a congenital anomaly in the structure of the uterus - a bicornuate or saddle uterus. A certain sequence of such pathologies has also been noticed - if a woman had low placentation in a previous pregnancy, with a high degree of probability the attachment of the fetus and the development of the chorion during a subsequent pregnancy will also be low.

Symptoms of the marginal presentation of the chorion in the early stages may not be, but small, short-term spotting may appear. Usually they are always evaluated correctly by a woman - as a threat to the preservation of the child.

If the chorion, and subsequently the placenta, do not migrate, such bleeding associated with rupture of small blood vessels due to stretching of the walls of the uterus can be repeated frequently, in some - until the very birth. Because of them, a woman begins to suffer from anemia, she is chronically lacking in iron, and her blood contains a small amount of hemoglobin. Be that as it may, with the appearance of bloody discharge from the genital tract of a pregnant woman, an ambulance should be called immediately.

With timely hospitalization with the help of conservative treatment, it is possible to save up to 90% of all babies that grow in the mother's womb against the background of marginal presentation of the chorion, placenta and even the umbilical cord.

What to do?

As already mentioned, the marginal presentation of the chorion is diagnosed in about 4-5 women out of ten pregnant women up to 12 weeks. However, not all of them immediately fall into the risk group and the lists of patients for a planned caesarean section. The prognosis is favorable, and in 90% of cases, the chorion, and then the placenta, which forms in its place, migrates higher simultaneously with the growth of the uterus.

The baby in the mother's womb is growing rapidly. To meet his needs for comfort, the walls of the uterus and the ligamentous apparatus are forced to stretch. Together with them, the placenta, which at the beginning of pregnancy was in the marginal presentation, will “crawl” up. The placenta will migrate along the anterior or posterior wall of the uterus - it does not matter. It is important that in most cases it really rises, and all the threats and risks associated with low placentation remain in the past.

Medicine cannot influence the process of migration, speed it up or stimulate it. A woman diagnosed with chorionic marginal previa should follow all the recommendations of her attending physician, exclude physical activity, weight lifting, jumping, sudden movements, squats. She will have to visit her doctor more often, do ultrasounds to track the process of migration of the chorion (placenta). Sex with marginal presentation is prohibited, since an orgasm associated with contraction of the muscles of the uterus can contribute to the rapid traumatic detachment of the chorion and the occurrence of severe bleeding, in which the child may die in utero, and the woman may lose a lot of blood and die already from this.

The process of placental migration is usually completed by 18-20 weeks of gestation. By this date or a little later (by 35-28 weeks), the true state of affairs becomes clear - if the placenta has risen, the restrictions will be lifted, if not, the pregnant woman will be classified as a risk group for preterm birth and will continue with increased attention and trepidation.

Treatment

Migration cannot be accelerated, but treatment for a woman with marginal chorion presentation is likely to be prescribed. Only it will not be directed at the chorion itself, but at relaxing the muscles of the uterus in order to prevent its tone and not provoke new detachments and bleeding. Depending on the degree of presentation, treatment may be carried out in a hospital, or they may be allowed to take the necessary drugs at home. The doctor leaves this question to his discretion.