Full presentation of the fetus. Threats of placenta previa during pregnancy. Placenta previa: symptoms

The placenta is important body, the vascular bed of which provides nutrition to the fetus and protection from harmful external factors(hemo-placental barrier).

Usually the placenta is formed in the region of the uterine fundus. The smooth muscle wall does not interfere with the development of blood vessels. It is elastic and evenly stretches in accordance with the growth of the placenta, without interfering with its functions.

But other situations are possible when the placenta is fixed on the anterior wall of the uterus, and partially enters or. In this case, full or partial presentation is diagnosed.

If the placenta blocked the internal os by no more than 1/3 and touches it only with the lower edge - this is called marginal placenta previa .

If the marginal presentation is diagnosed in the early stages of pregnancy, then over time, during the growth of the uterus, the edge of the child's place can also rise, moving along with the uterine wall.

However, in the assessment of the alleged complications of placenta previa, plays a lot important role, the place of attachment of the placenta - along the back or along the front wall.

With marginal placenta previa on the back of the machine, the forecasts are quite optimistic: the risks by the end of pregnancy and during childbirth will be much lower.

However, if by the 24th week the placenta has not changed its position, the woman needs additional monitoring and a more gentle regime, limiting the load.

What is the danger to mother and child?

1. The growing fetus will put pressure on the body of the placenta, which can lead to circulatory disorders, the appearance of foci of ischemia, and early aging of the placenta.
2. The lower segment of the uterus is less plastic and cannot always stretch, corresponding to the size of the placenta, and this, with bleeding, is an extremely dangerous condition for the life of the mother and fetus.
3. Even if the pregnancy proceeded normally, the internal os is not blocked and the woman is allowed to give birth naturally, there is a risk of complications. During contractions, the lower edge of the placenta can block the birth canal. As a result, the newborn may die.
4. Or, passing through the birth canal, the baby will “pull” the body of the placenta along with it - this is fraught with a sharp separation and heavy bleeding.

Complications during natural childbirth are an indication for an emergency caesarean section.

Causes of the pathological location of the placenta

Doctors do not know how to influence the placenta fixation, this process is uncontrollable.

But some reasons are known that increase the risk of an abnormal location of the placenta.

Some of them are associated with pathology. gestational sac, others - with the somatic health of the woman herself.

Appropriate preventive measures can reduce the likelihood of incorrectly securing a child seat.

Anomalies of the ovum

• genetic diseases that affect the development of the fetus
• taking strong medications
• environmental factors

All of these reasons disrupt the formation of chorionic villi or their weakness, as a result of which they do not have time to penetrate into the endometrium of the upper uterus and are fixed only when they fall below.

Maternal health reasons

• Bad habits.

Smoking, alcoholism, drug addiction lead to vascular disorders.

Not finding a place adequate nutrition in the area of ​​\u200b\u200bthe day of the uterus, the fetus is fixed closer to the neck - the places where large vessels pass.

• Chronic diseases of the mother.

Diabetes, high cholesterol, heart failure, which also lead to blockage of blood vessels, resulting in impaired blood supply to the upper uterus.

• Frequent vaginal infections or endometriosis.

As a result of inflammatory processes, the endometrium becomes thinner and its thickness and density is not enough to fix the chorion in the desired section of the uterus.

• Multiple births.
• Frequent abortions.
• History of caesarean section.
• The presence of myoma.
• Late first pregnancy (mother's age over 30 years).

Symptoms

As a rule, marginal placenta previa is diagnosed during an ultrasound examination even before the appearance of external signs troubles.

But if a woman for some reason did not do it or the placenta is on back wall and the position of the fetus in the uterus does not clearly define its localization - in this case, some external signs may indicate a low presentation.

In the early stages, the doctor may be alerted by a highly raised bottom of the uterus (not corresponding to the gestational age). The placenta, located below and actively growing, seems to push up the “light” uterus with a thin bottom.

More characteristic symptom can be called intermittent bleeding. They are not accompanied or disturbed by the child.

The reason for them is the excessive pressure of the low placenta on the vessels of the vagina. small vessels burst, unable to withstand the load. This is the source of bleeding. Usually it passes quickly and is not dangerous for the baby, since placental blood flow not affected.

But as the fetus grows, later dates pregnancy, especially slim women, bleeding from external vessels becomes frequent. Hemorrhage can.

More dangerous are bleeding caused by. They are plentiful, may be accompanied by pain, require emergency hospitalization.

Diagnostics

A presumptive diagnosis of placenta previa can be made as a result of manual palpation examination or by. To clarify the diagnosis is prescribed.

Ultrasound examination allows you to accurately determine the position of the body of the placenta and, most importantly, the localization of its edges.

Its size, thickness, distance from bottom edge before internal os. The probability of possible complications depends on this parameter.

What to do with marginal placenta previa: treatment methods

To reduce pressure on the edge of the placenta and the vessels of the vagina, a woman should wear a special bandage, avoid physical exertion, stress, accompanied by lifting blood pressure, avoid sexual intercourse.

There are recommendations to get on all fours 3-4 times a day. Thus, reducing the pressure on the lower edge of the placenta. And at the same time, by stretching the anterior wall of the uterus, you can sometimes achieve some upward displacement of the placenta. Exercise is effective in the second trimester.

Drug treatment includes vascular and antiplatelet drugs in doses that are safe for the fetus.

As a rule, women with marginal presentation for a period of 24 weeks are hospitalized in a hospital for a series of preventive measures including:

• tocolytic therapy.

The expectant mother is prescribed a number of drugs designed to reduce the contractile activity of the uterus. Most often, "Ginipral", "Partusisten" are prescribed, which are administered intramuscularly or drip;

• prevention of fetoplacental insufficiency.

Vitamins are prescribed, as well as drugs that improve blood circulation - "", "Actovegin", "Trental";

• anemia prevention.

Be sure to take drugs that increase;

• taking antispasmodics.

The action of these drugs is aimed at reducing the existing tone of the uterus. Women are prescribed either taking No-shpy, as well as magne-B6, magnesium sulfate.

If exists high risk premature birth due to placental abruption, corticosteroid therapy (Dexamethasone, Hydrocortisone) is additionally carried out to prevent respiratory disorders in the infant.

Conducting childbirth with marginal presentation

If the exercises and the bandage did not help to change the level of the placenta, and according to ultrasound, the marginal presentation persists, at a period of 36-38 weeks, a decision is made to possible way delivery.

In any case, the decision is made by the obstetrician-gynecologist who will conduct the birth. In this case, early hospitalization may be required.

If a woman has no bleeding with marginal presentation, natural childbirth is possible.

In this case, when opening by 3 fingers, a prophylactic amniotomy is performed.

Even if there is bleeding, some obstetricians allow you to give birth yourself. If the cervix is ​​soft and smoothed, an amniotomy is performed even before contractions, due to which the child descends and presses against the entrance to the small pelvis and presses the exfoliated lobules.

This allows you to stop the bleeding. Oxytocin is also prescribed, which, on the one hand, prevents profuse blood loss during childbirth, and on the other hand, accelerates labor activity, causing frequent and strong contractions.

If the amniotomy did not bring desired results, a woman with bleeding is delivered by the abdominal route.

In the case when, in addition to ultrasound data, bleeding is also present, early operative delivery is possible (up to 36 weeks).

Bleeding limits the use of antiplatelet agents to improve blood flow. In addition, developing anemia threatens fetal hypoxia and deterioration in maternal health.

If a woman is being prepared for a caesarean section at 36 weeks, the baby will also be prepared for early appearance into the world. Medicines accelerate the formation of alveoli in the lungs.

According to ultrasound, it will be possible to assess the maturity of the fetus and the readiness of its organs for life outside the mother's body. Perhaps such a baby will have to spend some time in the premature ward, but it will be much safer for his life and health.

With the diagnosis of "marginal placenta previa" doctors encounter infrequently. But if the pathology of the location of the child's place is confirmed, the pregnant woman requires additional monitoring, possibly with drug therapy.

If a woman follows the instructions of the doctor, treats the imposed prohibitions with understanding and seriousness, she has every chance to give birth to a healthy and strong baby.

Placenta previa is a type of pathology in which the location of the placenta is concentrated on the side of the lower segment in the uterus. Placenta previa, the symptoms of which are partial or complete blockage of the internal os, is diagnosed in the range of 0.1-1% of all cases of childbirth. You can learn more about the features of this pathology from our article.

general description

To get a general picture of the problem that a certain part of pregnant women have to face, it is necessary to understand what the placenta is and what functions it performs.

From the Latin language, the placenta is translated as "flat cake", which in general terms allows us to make an assumption about the features that are characteristic of it. This definition applies in particular to appearance. The placenta, or, as it is also defined, a child's place, actually looks like a cake: its thickness is about 3-5, and its diameter is about 15-20 centimeters with a weight of about 500 grams ( indicated indicators are limiting and relevant by the end of the term). By itself, such a “cake” is loose and soft.

The placenta also has many functions, due to which care is provided that corresponds to the conditions for the child to be in the mother's body. In particular, this is the nutrition necessary for its growth and development, protection, due to which the exclusion of harmful substances from entering its body is ensured. The placenta also has a hormone-forming function, which is why the placenta is also an endocrine organ that ensures the production of hormones. They, in turn, are such active substances, due to which the correct functioning of the mother's body during the period of bearing a child is ensured. Metabolic processes (carbon dioxide and oxygen) are also provided through the placenta, as well as the removal of unnecessary substances.

Placenta previa: causes

Factors provoking placenta previa can be divided into two main groups:

• factors due to the general condition of the body of a pregnant woman;
• factors due to features characteristic of the fetal egg.

In the first case, when considering the factors due to the state of the body of a pregnant woman, among the most common causes, the following can be distinguished:

• pathology of the endometrium;
• surgery in the past C-section, curettage, uterine perforation, myomectomy, etc.);
• multiple births with complications.

Among the etiological factors of this paragraph, endometriosis, uterine fibroids, underdevelopment or other types of anomalies that directly relate to the uterus can also be distinguished, multiple pregnancy, pathology of the cervix, endocervicitis, etc. Separately, it should be noted that placenta previa in about 75% of cases is a very characteristic pathology for re-pregnant women (relative to primiparas).

As for our second point, specific processes are considered here: a violation of trophoblast implantation with a belated occurrence of enzymatic processes in the trophoblast, against the background of which the timely implantation of the fetal egg in the upper uterine regions is disrupted. This process is relevant only when the fetal egg has descended to the lower uterine sections.

On the basis of these processes, according to the second paragraph, it is possible to identify the corresponding risk groups during pregnancy according to the following factors that occurred earlier:

• a burdened version of the obstetric and gynecological history (this includes diagnostic curettage, numerous abortions, complicated childbirth, etc.);
• genital hypoplasia;
• the transfer of earlier surgical interventions directly related to the organ of the uterus;
• uterine fibroids;
• inflammatory diseases of the genital organs;
• pathology of the cervix;
• endometriosis.

Placenta: what is this organ and what are its functions

The placenta (and this is precisely the organ, as noted in our subtitle) does not begin to form immediately, but from the third week of the term prenatal development fetus, it does not immediately begin to function - the "start" of this process occurs by the end of the first trimester of the gestational age.

The structure of the placenta changes gradually, in accordance with the needs that the body of a growing child determines. Thus, the mass of the placenta increases during the 22-36th week of pregnancy, from the 36th week we can talk about its full functional maturity. The maturity of the placenta is determined on the basis of compliance with the three degrees used for comparison. So, in the normal variant, until the 30th week of the term, the degree of maturity is determined as zero. A first-degree fit from weeks 27 to 34 may be considered a valid option. For the second degree of maturity, a period of 34-39 weeks is determined, from 36-37, respectively, we can talk about the third degree of maturity. The completion of pregnancy is accompanied by a period of so-called physiological aging of the placenta. Its exchange surface decreases in area, and areas are also formed on it, within which salts are deposited.

Based on the ultrasound data, the doctor during the patient's pregnancy determines the degree of maturity of the placenta when assessing its overall structure and thickness. According to the degree of maturity of the placenta and the duration of pregnancy, the doctor also selects a specific tactic for managing pregnancy. This information is also the basis for the tactics of subsequent delivery.

Remarkably, the mixing of the blood of the mother and her unborn child in the placenta does not occur - their blood circulation is a completely disconnected process. Facing the wall of the uterus, the surface of this organ has many villi. These villi grow into the endometrium (the inner surface lining the organ of the uterus), which by the beginning of this process is in a “prepared”, swollen state. Gaps are also formed here - cavities in which maternal blood is located. In this area, thus, the fetoplacental barrier is formed. Due to the thin membrane, an obstacle is provided for mixing blood, as well as getting to the child from the mother's body nutrients and oxygen through the blood.

The phytoplacental barrier is also the basis for preventing the ingress of certain harmful substances that are dangerous for the child. Nevertheless, “giving up” on everything because of the presence of such a caring mechanism in your own body will not work. After all, say, the same alcohol easily seeps through such a barrier, and therefore the child is completely defenseless under such an impact. Against the background of a violation of the functions characteristic of the placenta, oxygen starvation of the fetus develops, and a lack of nutrients occurs. Finally, as one of possible pathologies hypotrophy may become relevant.

Hypotrophy, in turn, is a chronic eating disorder that occurs, as is already clear, against the background of insufficient intake of nutrients into the body or against the background of a violation of their absorption. The result of malnutrition is the low weight of the child, which, depending on the degree of manifestation of this disorder, can reach a weight deficit ranging from 11 to 30% or more (in the latter case, determining the extreme degree of exhaustion). In addition to lack of weight, against the background of malnutrition in children, again, depending on the degree of its manifestation, there is a lag in growth, a lag in mental development, thinning of the subcutaneous layer or its complete absence.

The normal course of pregnancy consists in the location of the placenta from the side of the bottom of the uterus, during its transition to the side walls and to the back wall. Somewhat less often, it happens that the placenta is located on the side of the anterior uterine wall, which has its own explanation. The point here is that it is the front wall that undergoes the most transformations. In addition, the anterior wall of the uterus, located near the abdominal wall, is subject to possible injury. Again, if we dwell on the main function assigned to the placenta by nature itself, and this, as we have already noted, is the supply of the fetus in the mother's body with oxygen and nutrients. The distribution of nutrients occurs through the blood vessels, and this explains the peculiarity of the location in the uterus of the child's place, and it is located within the most blood-supplying areas.

Childbirth: what happens to the placenta

Considering, again, the flow normal pregnancy, we get the following picture. The placenta is located in this case not lower than a distance of 5 centimeters from the internal exit from the cavity of the organ of the uterus, closed during the course of pregnancy, this exit is also defined as the internal os of the uterus. The uterus of a woman during pregnancy is relaxed, the blood circulates freely in it, the pharynx is in a closed position. When childbirth begins, active contraction of the uterus begins. This is accompanied by the simultaneous relaxation of its lower segment, as a result of which the cervix begins to gradually open, the diameter of the pharynx begins to change (it reaches 10 centimeters). Due to these processes, in turn, the possibility of passing the child is ensured.

We have already noted that hormones are synthesized by the placenta, while certain of these hormones provide the creation of a platform for the uterine wall. Such a platform is not reduced, therefore, during the period of labor, normal blood circulation is ensured between the mother and the child. In addition, it also ensures the exclusion of the possibility premature detachment placenta.

But if we consider the situation with placenta previa, then with the onset of childbirth, the situation is subject to certain changes. So, in this case, the placenta is in such conditions under which the onset of labor will be accompanied by its inevitable detachment. This, in turn, will lead to bleeding, against which the child ceases to receive oxygen and the required nutrients, as a result of which, ultimately, his death occurs due to hypoxia.

Returning to the normal course of childbirth, we note that the placenta normally comes out about 15 minutes after the baby is born. With it, the placenta (fetal membranes) also comes out. Placenta after childbirth without fail is examined by the doctor who took delivery of the woman. This is done in order, first of all, to ensure the complete exit of the placenta (in particular, it is important to determine the absence of damage on its surface, which could act as a justification for the fact that its pieces remained in the uterus). In addition, on the basis of the state of the placenta, it will be possible to judge the peculiarities of the course of pregnancy (this concerns the relevance of infectious processes, detachment, etc., during its period).

Improper attachment of the placenta: types

The placenta at the initial stage of its formation can attach anywhere, and in most parturient women it is concentrated quite low. And if this is exactly what happens within the period of 11-16 weeks of the term, this is not critical, therefore it is not worth talking about placenta previa yet. The fact is that it can not only be located anywhere, but is also predisposed to a certain “migration”, which it carries out within the framework of the uterine wall, upwards. Already by the onset of childbirth, the placenta, therefore, may be on the side of the back wall or even in the fundus of the uterus. Accordingly, there is a chance that the placenta will change its position in this way until the 24th week - it is after this period that the final verdict on its position is announced on the basis of ultrasound and the diagnosis of placenta previa is established.

This pathology can manifest itself in the following ways:

• low presentation placenta;
• marginal placenta previa;
• complete placenta previa (or central placenta previa).

Low presentation determines the location of the placenta at a distance below 5 centimeters from the os of the uterus, without overlapping it. marginal presentation placenta (incomplete or partial presentation) is characterized by bringing the lower edge of the placenta to the borders of the uterine os or partially overlapping it with the placenta. Complete placenta previa is the most dangerous, the uterine os with it completely overlaps.

Placenta previa: symptoms

As the leading manifestation of symptoms in the pathology under consideration, bleeding arising from the genital tract of a pregnant woman is considered. They appear on various stages the course of pregnancy (from the first trimester until the onset of childbirth) are characterized by their own recurrence. Meanwhile, most often such bleeding is diagnosed from the second half of the term, which is associated with the formation of the lower uterine segment. Increased bleeding can be observed within the last week of pregnancy, which is caused by increased intensity uterine contractions. Bleeding with placenta previa is diagnosed during pregnancy in about 34% of patients, while bleeding during childbirth occurs in 66%.

The main cause of bleeding in this case consists in the repeated detachment of the placenta, which does not have the ability to stretch after the stretch that occurs from the side of the uterine wall and is dictated by the progression of the pregnancy itself (in other cases, this is due to the onset of labor). Partially, detachment of the placenta occurs when the intervillous space is opened and bleeding occurs from the uterine vessels. Accordingly, the fetus does not experience blood loss. However, for him there is another threat - in the form of hypoxia (oxygen deficiency), because the part of the placenta that has undergone exfoliation does not participate in gas exchange.

As provoking factors against which bleeding can develop during pregnancy, sexual intercourse, increased physical activity, defecation, the use of thermal procedures (taking hot baths, visiting a sauna, etc.), conducting a vaginal examination, and even a sharp attack of coughing are considered.

Bleeding may vary depending on the type of placenta previa. So, complete placenta previa characterized by sudden onset of bleeding, possible profusion and lack of pain. Such bleeding may stop, reappearing after a while, or it may not stop, but, having subsided somewhat, appearing as a meager type of discharge. Within the time limit recent weeks during pregnancy, bleeding is subject to resumption and/or intensification. As we have already noted, this form of presentation as a whole is the most dangerous of the options. The death of a child with this variant can occur very quickly, moreover, this pathology is no less dangerous for the woman in labor. Regarding the outcome of such cases, assumptions can be made on the basis of the speed of surgical intervention. In particular, this is a planned caesarean section, performed without waiting for the first contractions to appear in the woman in labor.

Incomplete presentation placenta characterized by the onset of bleeding by the end of the term, mainly within the onset of the opening period, and in some cases even later (that is, when smoothing occurs, when the pharynx opens by about 4-5 cm). As for the intensity of bleeding, it is determined on the basis of the value corresponding to the presenting area of ​​the placenta. That is, the greater the part of the placental tissue is, respectively, the more intense and earlier the bleeding occurs.

Separately, we note that such a presentation itself is rare in manifestation. The overlap of the uterine os, as already noted, occurs here in a partial way, bleeding begins mainly during childbirth, stops quickly, which is facilitated by lowering the baby's head into the pelvic cavity while pressing the exfoliated edge of the placenta. Permission to give birth is allowed independently, unless other risk factors are excluded, and also if there is the possibility of an immediate caesarean section if there is a threat to the life of the baby and the woman in labor.

As for the situation in which a woman in labor is diagnosed with " low placentation” (low presentation), then it is the least of the concerns when considering the previous options. Bleeding, as well as other manifestations, are absent during pregnancy. Basically, childbirth takes place independently, although special control is still necessary here - in case of a prompt response in case of possible placental abruption (the risk of such a situation is small), as well as when bleeding begins during labor.

When considering the specifics of bleeding in placenta previa, it is important to note the fact that in some cases their intensity and degree of placenta previa do not match. Thus, options are not excluded in which complete placenta previa may be accompanied by minor bleeding, while incomplete, on the contrary, is accompanied by extremely heavy bleeding.

So, let's highlight those features of bleeding in placenta previa, which, in fact, correspond to this pathology:

• in any case, such bleeding is external;
• characterized by suddenness of occurrence;
• secreted scarlet blood;
• visible external causes that provoked bleeding are absent;
• often such bleeding occurs at night (literally, a pregnant woman wakes up in a pool of blood);
• having suddenly appeared, bleeding can also suddenly stop;
• in any case, the bleeding is repeated.

As for the last point on re-bleeding, its nature cannot be foreseen. The external blood loss that was taken into account may not correspond to the true volume of blood loss, the degree of manifestation of anemia in all cases is high. It should be noted that in the vast majority of cases Iron-deficiency anemia develops frequently enough we are talking about the consideration of the pathology in which bleeding during pregnancy against the background of placenta previa have a recurring nature of manifestation (and such bleeding, as already noted, is exactly recurring in all cases). It implies the appearance of severe weakness, shortness of breath and palpitations, pallor of the skin (including mucous membranes, with a possible cyanotic tint), dizziness and trembling of the extremities against the background of a general condition.

In many cases, pregnancy with placenta previa determines the risk of it possible interruption, which is most likely due to the same reasons that provoked the abnormal location of the placenta. Most often premature birth occur in those pregnant women in whom placenta previa is complete.

Also, pregnant women with a diagnosed placenta previa often face arterial hypotension(low blood pressure), this violation is noted in the range of 25-35% of cases.

It is no exception for placenta previa and preeclampsia. Preeclampsia is such a complication of the course of pregnancy, in which a number of disorders occur regarding internal organs and systems in the body. It is assumed that the basis of this condition lies in a generalized vasospasm, which entailed a number of corresponding changes. With early gestosis, patients are diagnosed with vomiting (often excessive, indomitable), profuse salivation. With late gestosis, dropsy is noted (accumulation of fluid in the tissues, organs and cavities of the body), nephropathy (kidney pathology), preeclampsia ( pathological condition, against which pregnant women develop swelling, blood pressure rises and protein appears in the urine), as well as eclampsia (a form late toxicosis during pregnancy).

Placenta previa is also often accompanied by the development of placental insufficiency and fetal hypoxia, as well as a delay in its development. Due to the disconnection of the placenta, which has undergone detachment, from common system uteroplacental form of blood circulation, its participation in the processes associated with gas exchange is excluded. Based on this, in determining the degree of hypoxia, they are repelled from the area of ​​placental detachment.

An urgent problem with placenta previa also in many cases becomes the adoption of an incorrect position by the fetus (transverse or oblique), is not excluded and breech presentation. This, in turn, creates additional complications.

Regarding the frequency of placenta previa, we note that within the second trimester it is diagnosed 8-10 times more often than, respectively, by the onset of labor, which is due to the “migration” already briefly noted in our article. "Migration" in particular occurs during the second and third trimesters to the upper uterine region.

In fact, "placental migration" as a term is not a reflection of the actual specifics of the ongoing processes, despite the fact that it is quite firmly established in obstetric practice. Let's take a look at it at a slightly deeper level.

Thus, the localization of the placenta changes, in particular, due to changes that occur in the architectonics of the lower uterine segment during the course of pregnancy, as well as the direction of placental growth towards more vascularized areas of the myometrium (in comparison with the lower uterine segment).

As such, the transfer of the placenta does not occur, this is a somewhat "blurred" definition. In other words, she, being in unfavorable conditions for her (which is important when implanted in an area with a weakened blood flow), often grows to the bottom of the uterus, which, in turn, has a much better blood supply. In addition, during pregnancy, a number of serious structural changes occur on the muscular wall of the uterus, as a result of which some of the layers seem to “move” to the upper uterine sections, that is, “migrate”. Accordingly, with these layers, the placenta itself is removed from the internal pharynx, which becomes the reason for such a definition of the process, but by no means indicates its global movement in the literal sense of the word.

The option of an unfavorable prognosis in terms of such a “migration of the placenta” is determined by its location on the side of the anterior uterine wall in the event that its normal blood supply is relevant. For other cases, as also discussed earlier, such migration determines the chances for positive changes.

Diagnosis

Diagnosis of placenta previa is not particularly difficult, it is performed by the method of ultrasound (ultrasound). In this case, high accuracy is determined in identifying the area of ​​localization of the placenta, as well as in identifying a number of other specific features that accompany the course of pregnancy (characteristics of blood flow, structure and thickness of the placenta, etc.). In addition, there are a number of signs, on the basis of which the detection of pathology is also carried out as part of the examination of the patient in the chair (feeling the alleged area of ​​\u200b\u200bthe location of the head reveals the presence of a pasty formation). Separately, during such an examination, bleeding coming from the genital tract (painless, repetitive, bright scarlet) is taken into account.

Treatment

Features of the management of pregnant women and their treatment in placenta previa is carried out on the basis of the severity of actual bleeding and the amount of blood loss. Within the first half of the term, with no blood discharge, the patient can stay at home, provided that appropriate outpatient monitoring is provided and the regimen is observed. In the latter case, it is supposed to exclude such factors that can provoke bleeding (increased load, stress, sex life etc.). As for the observation and the required treatment, it is carried out only in an obstetric hospital.

Methods of conservative therapy can be focused on lengthening the gestational age up to 37-38 weeks (with light bleeding and a satisfactory condition of the pregnant woman and the fetus). The drugs used in the treatment, given the seriousness and individual specifics of the approach in each specific case, we will not consider in detail in our article. Separately, of course, it should be noted that any self-medication and treatment with folk remedies for placenta previa are too risky measures that the expectant mother should be excluded in order to avoid negative consequences and in an already serious situation.

Caesarean delivery with placenta previa is carried out regardless of specific date pregnancy in the following emergency situations:

• recurrence of blood loss in case of loss of blood in a volume of more than 200 ml;
• small blood loss is combined with hypotension and anemia;
• simultaneous and volumetric blood loss (from 250 ml of blood loss or more at a time);
• the onset of bleeding with complete placenta previa.

The operation is performed in accordance with the vital indications of the mother, regardless of the condition of the fetus and the duration of pregnancy. With successful prolongation of pregnancy until the period of 37-38 weeks, with the preserved variant of placenta previa, an adequate method of delivery is determined.

Again, as an absolute option for caesarean section, the option of complete placenta previa is considered. Incomplete presentation in combination with concomitant complications (incorrect position of the fetus, breech presentation, the age of the primiparous mother over 30 years, narrow pelvis, burdened history, etc.) also requires a caesarean section.

Observation and management of pregnant women, as well as the diagnosis of placenta previa, is carried out by a gynecologist.

Joseph Addison

With the help of exercise and abstinence, most people can do without medicine.

Which doctor to contact

If you suspect a disease such as Placenta Previa, you should consult a doctor:

- pathological attachment of the embryonic organ, which provides a connection between the mother and the fetus, in which there is a partial overlap of the internal os of the uterus (no more than a third of it). Clinically, the disease is manifested by bleeding of varying intensity, not accompanied by discomfort. It is possible to identify marginal placenta previa with the help of a planned ultrasound in the second trimester or when pathological signs occur. Treatment involves hospitalization, bed rest, symptomatic therapy. Expectant management is indicated before the term of the expected birth, provided normal state woman and fetus.

Marginal placenta previa can lead to placental abruption. This is due to the fact that the lower segment of the uterus has less ability to stretch. Also, marginal placenta previa often provokes massive bleeding during childbirth. Such an outcome is possible during natural childbirth, if there was a sharp separation of the membranes as a result of the passage of the fetus through the birth canal. In obstetrics, placenta previa occurs predominantly in repeated pregnancies. Pathology requires careful monitoring, since in about 25% of cases it is accompanied by stillbirth.

Causes of marginal placenta previa

Marginal placenta previa may be due to abnormal attachment of the trophoblast during implantation or anatomical features of the myometrium. In the latter case, a violation of the structure of muscle fibers in the wall of the uterus occurs against the background of inflammatory changes, the consequences of genital infections. Marginal placenta previa is more often diagnosed with thinning of the myometrium, provoked by frequent curettage and abortion. Also, the cause of abnormal attachment of the trophoblast can be uterine deformities caused by benign tumors or resulting from congenital pathologies.

Marginal placenta previa often develops in women with comorbidities internal organs, in particular, in pathology of cardio-vascular system. due to poor circulation and congestion in the small pelvis, the placenta cannot fully attach. In addition, marginal placenta previa is possible against the background of abnormal development of the embryo immediately after fertilization. A similar outcome is observed with a belated appearance of the enzymatic functions of the trophoblast. As a result, it attaches to the myometrium later than it normally does, staying in the lower part of the uterus.

Classification of marginal placenta previa

Marginal placenta previa can be of two types, depending on the place of its attachment:

• Localization on the front wall- the most dangerous variant of the course of pathology. With marginal placenta previa of this type, there is a high risk of its mechanical damage followed by detachment due to physical activity woman, movements of the baby, against the background of a strong distension of the uterus in the third trimester of pregnancy. Despite this, when placing the embryonic organ on the anterior wall of the uterus, there is a possibility of its movement upwards.
• Back wall attachment- a more favorable variant of the marginal placenta previa. It is accompanied by a lower risk of complications in the process of gestation and childbirth for the mother and baby.

Both types of anomalies are a pathology of pregnancy and require mandatory monitoring by an obstetrician-gynecologist.

Symptoms and diagnosis of marginal placenta previa

Marginal placenta previa has a characteristic symptomatology - the appearance of spotting without worsening overall well-being. Often this pathological sign occurs at rest or at night. As for the timing of embryogenesis, the marginal placenta previa manifests itself mainly at 28-32 weeks. It is during this period that the uterus differs increased activity due to the preparation of the myometrium for the upcoming birth. Somewhat less often, abnormal discharge is observed already at the beginning of the second trimester. The volume of bleeding can be different and depends on the degree of damage to the vessels.

With marginal placenta previa in the third trimester of pregnancy, bleeding can be triggered by physical activity, sexual intercourse, fetal movement and other factors that provoke rupture of nutrient vessels. Appearance this sign possible even when gynecological examination. Sometimes marginal placenta previa is combined with the threat of miscarriage. With this combination, there is discomfort in the lower abdomen, uterine hypertonicity. With systematic bleeding in pregnant women with such a diagnosis, iron deficiency anemia develops. IN similar cases there is increased fatigue, weakness. On the part of the fetus, growth and development may be slowed down, hypoxia due to insufficient intake of nutrients. Marginal placenta previa is often associated with wrong position fetus, which may be oblique or transverse.

The preliminary diagnosis is established on the basis of the patient's complaints about bloody issues in the absence of pain. Another feature abnormal location of the embryonic organ - high standing of the uterine fundus, which does not correspond to the period of embryogenesis. It is possible to confirm the marginal presentation of the placenta with the help of ultrasound. During the scanning process, a specialist can accurately visualize the location of the placenta and the degree of overlap of the uterine os, determine the condition of the child and assess the possible risks to the woman and the fetus.

Treatment of marginal placenta previa

Treatment of marginal placenta previa depends on the identified symptoms, the period of embryogenesis, as well as the condition of the expectant mother and fetus. If the diagnosis is established only on the basis of ultrasound scanning and bleeding is not observed, it is possible to control the patient's condition on an outpatient basis. Hospitalization is indicated if marginal placenta previa is accompanied by secretions of any volume of blood. In this case, it is required careful observation in the hospital. Women with such a diagnosis are assigned complete rest, it is recommended to exclude sexual intercourse and stress. You must wear a bandage. In the second trimester, special exercise therapy for pregnant women sometimes helps to correct the location of the placenta.

With marginal placenta previa, anemia often develops due to systematic blood loss. Therefore, pregnant women are shown a diet enriched with foods high in iron. The diet should contain red fish, offal, buckwheat, beef, apples. Pregnancy management with marginal placenta previa involves a protective regime in order to achieve the expected date of birth and the birth of a full-term baby. Also, patients with a similar diagnosis are prescribed medications, taking into account the general condition and comorbidities.

With marginal placenta previa, symptomatic drug therapy. With uterine hypertonicity, tocolytics and antispasmodics are used, and preparations containing iron are prescribed to eliminate anemia. To maintain the general condition of the patient and the fetus, vitamin complexes can be used. Sometimes, with marginal placenta previa, it is advisable to use sedatives. According to indications, antiplatelet agents are introduced, the doctor calculates the dosage of drugs in order to avoid a negative impact on the baby.

If marginal placenta previa is accompanied by massive bleeding, delivery is carried out regardless of the period of embryogenesis by emergency caesarean section. In case of full-term pregnancy, childbirth naturally permissible subject to the maturation of the cervix, active labor, good condition of the patient and the fetus. When opening the cervix by 3 cm, an amniotomy is performed. Oxytocin is administered to prevent bleeding. If, with marginal presentation, the placenta significantly overlaps the uterine os or childbirth through the natural canal is impossible, a caesarean section is indicated.

Forecast and prevention of regional placenta previa

The prognosis for marginal placenta previa is favorable. At timely diagnosis and compliance with medical recommendations, patients manage to carry the fetus up to 38 weeks and give birth completely healthy child. Marginal placenta previa can provoke the development of bleeding in the postpartum period. To prevent it, experts use intravenous administration of oxytocin. Prevention of pathology is the treatment gynecological diseases even before conception, the exclusion of abortion and invasive interventions on the uterus. After the onset of pregnancy, you should follow the doctor's recommendations, give up physical exertion, and avoid stress.

Successful gestation depends on many factors. One of them is the place of attachment amniotic sac. In case of deviations, placenta previa occurs during pregnancy. To prevent complications, it is necessary to identify the pathology and determine the causes of its occurrence.

In contact with

What is placenta previa

Often, when examining a condition in a pregnant woman, placenta previa is diagnosed. There is a need to study what it is and how it manifests itself.

Note! The fetal bladder plays an important role in the life support of the gestating fetus.

The bubble provides interaction between the body of the mother and the child. This body performs the following features:

• gas exchange;
• nutritional;
• immunoprotective;
• hormonal.

The physiological location of the fetal egg suggests its location on:

• the bottom of the uterus;
• posterior and lateral walls of the body of the uterus.

This area is the least affected. It is also the area of ​​the best vascularization.

Attachment to the back wall guarantees the protection of the embryo from unforeseen damage. When the bubble is attached from the side of the pharynx, then a violation occurs.

Placenta previa is pathological location fetal bladder.

As a result, the embryo develops into wrong place. It should be borne in mind that this condition directly affects the outcome of labor activity.

The danger of pathology lies in the limitation of delivery. Since the organ is located in the lower part of the uterus, the birth canal overlaps.

This state poses a threat to fetal development. Subject to detection of pathology increased likelihood:

• prematurity of the child;
• fetoplacental insufficiency;
• premature delivery;
• perinatal death;
• maternal death (against the background of blood loss and hemorrhagic shock).

This disorder is more commonly diagnosed in the early stages pregnancy. Closer to the 40-week period, the number of pathological cases decreases. This is due to "bubble migration". With the development of the fetus, the uterus is stretched, which leads to the displacement of the embryo from the cervical region.

Causes of placenta previa

Until now, there is no consensus on what affects the appearance of pathology. There is also no way to influence the placental formation. Generally causes of presentation placenta can be divided into the following categories:

1. Aspects of embryonic development.
2. Aspects that determine the health of a pregnant woman.

To features embryonic structure accepted to refer to:

• trophoblast implantation failure;
• weakly expressed enzymatic action;
• delay in the development of the fetal egg.

The presence of these factors makes it impossible to implant the fetus in the upper section.

The state of the mother's body is determined by such phenomena:

• inflammation in the endometrium (often);
• processes of endometrial atrophy;
• diseases of an infectious nature;
• stagnant processes V reproductive organs(are a consequence chronic pathologies cardiovascular and endocrine systems, as well as slow blood supply);
• surgical intervention in the uterus;
• cases of the gestation period;
• complications after previous labor activity;
• abnormal structure uterus;
• detection of endometriosis and uterine fibroids;
• underdevelopment of the uterus;
• the presence of isthmic-cervical insufficiency;
• the presence of endocervicitis;
• pathological processes in the cervical region;
• neuro-endocrine disorders;
• previously diagnosed facts of pathological location;
• susceptibility to addictions (systematic use of nicotine, alcohol-containing liquids and narcotic substances);
• multiple pregnancy;
• hormonal imbalance.

These causes of placenta previa affect the formation of the mucosa in the uterus. With its underdevelopment, an acceptable place is Bottom part cavities.

Placenta previa: types

In medical practice, it is customary to distinguish different kinds violations . Their classification is based on the following factors:

• determination of the location of the fetal egg using transvaginal ultrasound;
• identification of the location of the ovum during labor (the condition for fulfillment is the presence of a 4-centimeter opening of the cervix or more).

The results of transvaginal examination allow the division of pathology into the following types:

• complete;
• incomplete;
• low.

The data obtained during delivery determine the existence the following types violations:

• central;
• lateral;
• edge.

Complete placenta previa

Full presentation is presented in the form of a thorough overlap of the placental tissue of the cervix.

This position of the fetal bladder creates restrictions for natural delivery. Even with full cervical dilatation, the fetus won't be able to continue movement along the birth canal.

Full presentation is also known as the central position.

Its peculiarity is the need for . Other types of pathology do not exclude the possibility that the fetal bladder will move. In the case of the central type, there is no such outcome of events.

Central placenta previa dangerous with the following consequences:

• complete placental abruption long before labor;
• the occurrence of embryonic hypoxia;
• slow development of the child;
• increment of the fetal egg;
• early rupture of the membranes.

This attachment provides for complete exclusion of intimacy and minimizing physical stress.

Incomplete placenta previa

An incomplete placenta previa is partial overlap internal opening of the cervix. With this arrangement, a small area remains free.

An incomplete placenta previa is also known as a partial. A subspecies of this pathology is the marginal and lateral location.

Marginal location determines the presence of the lower part of the fetal egg near the edge of the internal opening of the cervix. At the same time, it can be both along the front wall and along the posterior arch. A single level is noted for the cervix and placental margin. With a lateral arrangement, there is a partial overlap.

This violation determines the impossibility of passing the child's head into the neck. This feature makes it possible to caesarean section.

Marginal placenta previa can be diagnosed by the anterior wall.

Attachment of the placenta along the anterior wall is an option gynecological norm. Such a case is not usually classified as pathological attachment.

This is due to the possibility of stretching the uterus under the weight of the fetus and its further advance along the anterior wall.

The marginal placenta previa along the posterior wall is usually classified as low or incomplete attachment of the fetal bladder. It manifests itself in the form of being in the back fornix.

This option is less dangerous than the location on the front wall. This is due to the difference in the load on the uterus. However, they may bleeding occurs.

Low placenta previa

What is low placenta previa during pregnancy, what threatens the condition of the expectant mother and child, are aspects of interest for study.

The low position implies that the amniotic sac is at the level less than 7 cm from the beginning of the cervical canal. There is no overlap of the placenta with the internal os of the cervix.

This position not considered a contraindication to natural childbirth. Among existing pathologies it is considered the most favorable for the period of gestation and childbirth.

There is the following classification of low location:

1. 1 degree (distance to the cervical canal - 3 cm);
2. 2 degree (there is a fixation of the fetal egg near the beginning of the cervical canal without blocking the entrance);
3. 3 degree (partial or complete overlap is noted, as well as placental displacement along the arch);
4. 4 degree (expressed complete blocking).

With the first two degrees, natural delivery is possible. The last degrees involve surgical intervention.

Danger of low presentation

Often, experts diagnose low placenta previa during pregnancy. What threatens this condition is the main issue in pregnant women.

Among the complications that arise against the background of such an arrangement, it is customary to single out:

• Risk of spontaneous abortion(occurs as a result of partial placental abruption; accompanied by increased tone in the area of ​​the uterus, systemic bleeding and lack of nutrient intake).
• Decreased blood pressure (accompanied by headaches, dizziness, fatigue).
• Anemia (due to blood loss; is the root cause of hemorrhagic shock).
• Incorrect attachment of the embryo (a response to insufficient space in the lower part of the organ).
• and risk retarded development child (impaired blood flow causes a limitation of oxygen volume and nutrients supplied to the fetus).
• The risk of placental displacement during natural labor with the impossibility of normal delivery.

The low location determines the importance of systematic monitoring of the course of pregnancy.

Cesarean section in pathology

C-section placenta previa is performed if:

• anamnesis in the form of diseases with a pronounced inflammatory nature;
• detection of polycystic or uterine fibroids;
• previous abortive termination gestation period;
• multiple pregnancy;
• gestation at a later age;
• early surgical intervention with violation of the integrity of the uterus;
• systematic blood loss in excess of 0.2 l;
• complete low position fetal bladder;
• foot or pelvic fetal position.

The above aspects serve as the basis for the planned surgical intervention. If there are no indications for a caesarean section with placenta previa, natural delivery occurs. If there is a threat to the life of the expectant mother or child, emergency intervention.

Note! It should be remembered that after the operation, the woman retains the possibility of subsequent childbearing.

Useful video: types of placenta previa

Conclusion

The gestation period may be accompanied by various anomalies. One of these pathologies is the placental location. This condition is diagnosed as a result of a vaginal examination. Timely detection of pathology allows you to choose the best method of delivery.

For full development the baby, "living" during pregnancy in the mother's tummy, requires a mandatory supply of oxygen and nutrients. In that direct involvement accepts the placenta.

What is this?

Placental tissue is a special specific organ that appears in the female body only during pregnancy. It begins to function actively by the beginning of the second trimester and persists until the very birth. main function The placenta is the protection of the child from the effects of the external environment, as well as participation in ensuring the blood flow necessary for its growth and development.

The placental tissue contains many different blood vessels through which important substances enter the body of the fetus. The intensity of intrauterine development of the fetus largely depends on what structure the placenta has and where it is located.

The maternal part of the placenta

Enter the first day of your last menstrual period

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 019 2018

Usually placental tissue is formed in the immediate vicinity of the site of implantation of a fertilized egg. In most pregnancies, implantation occurs in the upper part of the uterus - its bottom. As a rule, a fertilized egg is attached to the back wall, where the best blood flow occurs. However, this situation is not always possible. Sometimes it also happens that the attachment of a fertilized egg occurs much lower - in the lower sections of the uterus. In this case, the placental tissue is formed and is located quite close to the internal uterine os.

If the distance between the pharynx and the placenta is greatly reduced, then this clinical condition is called a low position. This can be very dangerous as the course of the pregnancy usually worsens.

If the placental tissue "enters" the area of ​​​​the internal uterine os, then such a pathology is already called presentation. In order to assess the presence of this pathology, doctors must evaluate the distance between the internal uterine os and the placenta itself. In each segment of pregnancy, the rate of this indicator is different. In the second trimester, the placenta should be normal 5 cm above the uterine os. In the third trimester, this value increases to 7 cm.

Presentation may be different. Doctors use special classifications, which include several clinical options. One of the rather unfavorable options is complete placenta previa. In this case, almost all placental tissue covers the uterine os. In this situation, the placenta is located critically low in relation to the external female genital organs. In this case, the risk of developing adverse complications during pregnancy increases many times over.

Causes

A variety of causative factors can lead to the development of a full presentation. The most common cause of this pathology is chronic diseases female genital organs. Pathologies that occur with the development of permanent inflammation are accompanied by damage to the internal mucous membrane of the uterus. Changes in the structure of the mucosa contribute to the fact that the fertilized egg simply cannot attach to the uterine wall in the region of its bottom. It begins to descend into the underlying sections, which leads to the formation of placenta previa.

One of the predisposing factors for the development of this pathology may be previous surgical operations on the reproductive organs. Curettage of the uterine walls, removal of myomatous nodes and various neoplasms are risk factors for the development of placenta previa. Doctors note that this pathology is more common in women who give birth to a second and subsequent babies.

Usually, the likelihood of developing placenta previa in a subsequent pregnancy is slightly higher in women who have previously had a caesarean section. And also the existing scars on the uterus that have arisen after gynecological operations can lead to the development of presentation.

How to identify?

Currently, it is quite simple to establish the localization of the placenta. Both a routine vaginal examination and an ultrasound test can help doctors with this. More exact method diagnosis of this pathology, of course, is ultrasound. Modern devices, with the help of which examination data are carried out, make it possible to calculate the distance between the placenta and the uterine os with an accuracy of a fraction of a centimeter. Complete placenta previa is a pathology that necessarily requires dynamic monitoring by doctors. For this purpose, specialists usually appoint expectant mother undergo several ultrasound examinations at regular intervals.

To assess the localization of the placenta in full presentation, doctors most often use transabdominal ultrasound. Conducting transvaginal studies and vaginal examinations may be fraught with the development of bleeding.

If they cannot be dispensed with, then in such a situation it is very important that the examinations be carried out by experienced and qualified specialists who will perform them with the utmost care and precision. The position of the placenta is also necessarily assessed immediately before childbirth.

Features of the development of pregnancy

When establishing the diagnosis of placenta previa, a more careful and attentive attitude of doctors is required. For the expectant mother, individual recommendations are made for correcting her lifestyle, which she must impeccably follow. It is important to remember that during the course of such a complicated pregnancy, conditions that are life-threatening to the fetus can occur at any time.

Usually the first unpleasant signs appear in the 2nd trimester of pregnancy. With complete placenta previa, they can develop in the 3rd trimester, and also disturb the woman almost until the very birth. In this case, it is important to monitor the well-being of the mother and child, and also to prevent possible dangerous states for their life.

If the expectant mother, who has placenta previa during pregnancy, felt sharp deterioration her condition, then she should definitely see her obstetrician-gynecologist.

Complications

Pregnancy complicated by placenta previa often does not proceed smoothly. Only in rare cases, carrying a baby does not cause any discomfort to the expectant mother. As a rule, a pregnant woman has various complications that aggravate the course of pregnancy. The most dangerous of them are the following:

1. development of bleeding from the genital tract;
2. detachment of the placenta from the uterine wall;
3. violation intrauterine process fetal development due to impaired blood flow through the uteroplacental vessels;
4. development of fetal hypoxia.

These clinical conditions usually develop in combination. The severity of adverse symptoms largely depends on how severe placenta previa is. With full presentation, these symptoms develop quite often. The course of this pathology is difficult to predict. A variety of reasons can lead to the development of complications.

So, bleeding from the genital tract can occur after lifting weights or doing intense physical activity. Even severe psycho-emotional stress can lead to a deterioration in the course of pregnancy.

Bleeding from the genital tract is one of the most common and unfavorable complications. The appearance of blood underwear the expectant mother herself usually notices. Blood clots in this case can have a different color: from dark brown to bright red.

In a pregnancy complicated by complete placenta previa, it is very important to remember that if blood appears from the genital tract, you should immediately seek medical help. If the bleeding does not stop for several hours, and the health of the pregnant woman worsens, then in such a situation, an ambulance team should be called immediately.

The visiting doctor can evaluate general state future mother and, if necessary, send her for hospitalization in a hospital.

During the stay in the hospital, the expectant mother will receive treatment aimed at improving her well-being. At the same time, doctors will definitely evaluate the general condition of the fetus. If the threat to life for the child is too great, and the gestational age is already sufficient for delivery, then in such a situation, most likely, a decision will be made to urgently perform surgical delivery.

Frequent bleeding from the genital tract is dangerous for the development of an extremely unfavorable condition for the expectant mother and her baby - anemia. The anemic state is characterized by a decrease in the amount of hemoglobin or red blood cells in the blood. Anemia renders negative impact on the intensity of intrauterine development of the fetus, and also significantly worsens the general well-being of a pregnant woman. To compensate for the violations that have arisen, the expectant mother is prescribed medications containing iron in their composition.