How does pregnancy proceed with marginal placenta previa? What to do with placenta (chorion) previa: marginal, central, low, complete? Marginal placenta previa

The placenta is one of several temporary organs that develop in a woman's body during pregnancy. It is difficult to overestimate the importance of the placenta in the development of the fetus: it is an intermediary between the child and his mother, transfers nutrients and oxygen from the mother’s blood to the baby, removes toxins and waste products from the fetus, filters the mother’s blood from harmful substances and infections, thereby protecting the baby, whose immunity until it is able to withstand the influence of the external environment.

Given all this, it is easy to understand why doctors are so closely monitoring the condition of the placenta, its location, and so on.

The placenta is formed only by the 4th month of pregnancy. Prior to this, its functions are distributed among other temporary organs: the fetal membrane and the corpus luteum, formed at the site of the bursting follicle. For the development of the baby, it is very important that the placenta is properly formed, and even its location is of great importance for the correct course of pregnancy.

What are the features of the location of the placenta, and how does it affect the course of pregnancy?

The most ideal option for the location of the placenta in the uterine cavity is to attach it along the back wall in the upper part of the uterus, closer to the bottom. The fact is that the walls of the uterus are designed in such a way that as the fetus grows, they stretch very much. However, they do not stretch evenly.

The uterus is designed in such a way that stretching occurs for the most part along front wall. It becomes thinner and more stretchable, while the back wall remains dense and much less prone to stretching.

That is why nature has laid down the attachment of the fetal egg precisely to the back wall, because the placenta, unlike muscle tissue, does not have the ability to stretch. Thus, the placenta fixed on the back wall experiences much less stress, which is not at all beneficial to it.

So it turns out that the back wall is an ideal option for attaching the fetus, and then the development of the placenta.

Options for the location of the placenta

For various reasons, the fetal egg can be attached not only to the upper part of the posterior wall of the uterus, but also to other parts of it. Quite often there is a side mount: to the right or left of the rear wall. In some, also not very rare cases, the placenta is fixed on the anterior wall of the uterus.

All these options for the location of the placenta are not considered pathology, although in such cases there is a deviation from the ideal location conceived by nature. Women with a lateral location of the placenta, as well as with a placenta attached to the anterior wall, most often carry and give birth to children naturally without complications. Of course, among them there are those who are faced with various pathologies, but, as a rule, they have other reasons for complications.

Certainly, placenta located on the anterior wall undergoes somewhat greater stress due to the constant stretching of the walls of the uterus, the movements of the fetus, the actions of the mother. To some extent, this increases the risk of damage to the placenta, premature detachment, and so on. The direction of placental migration may also change.

Due to the constant stretching of the muscles of the uterus, the placenta can gradually sink too close to the os of the uterus, and sometimes even block the exit from the uterus into the birth canal. If 6 centimeters or less remains between the edge of the placenta and the cervical os, they talk about, but if the placenta partially or completely blocks the exit from the uterus, this pathology is called placenta previa.

However, low placentation and placenta previa can be caused by a number of other reasons, which will be discussed later. Posterior presentation occurs much less frequently than along the anterior wall. We have already discussed why this is the case above.

Causes of anterior placenta previa

What are the causes of placenta previa on the anterior wall? Unfortunately, these reasons are not fully understood. However, some of them have already been established reliably. In particular, they include various endometrial damage- the inner layer of the uterus. These can be inflammatory processes, scars from operations, such as caesarean section, the effects of curettage after miscarriages or abortions.

uterine fibroids, as well as its other pathologies can cause placenta previa along the anterior wall. It is noticed that in women giving birth for the first time, this pathology occurs much less frequently than in the course of the second and subsequent pregnancies. It is connected, most likely, also with the state of the mucous membrane of the uterus.

However, not only on the part of the mother, there may be reasons for this pathology. In some cases, they are in underdevelopment fertilized egg. Due to this delay, the fertilized egg does not have time to implant in the endometrium in time. Implantation occurs in this case in the lower part of the uterus.

It also happens that the fetal egg is attached to the anterior wall in the upper part of the uterus, however, as a result, the placenta migrates as a result of the stretching of the uterus to the lower part.

Degrees of anterior presentation

Distinguish between full and partial presentation. It is easy to understand that full presentation The situation is called when the placenta completely covers the cervical os.

Partial presentation also divided into 2 different types: lateral and marginal. Regional - when the placenta passes along the very edge of the cervix of the uterus. Lateral presentation is when the placenta still blocks the exit from the uterus, although not completely.

Symptoms of anterior presentation and why it is dangerous

Unfortunately, very often anterior placenta previa proceeds completely asymptomatically. Of course, this does not mean that it will be impossible to diagnose pathology. Methods for defining the problem will be discussed later. The main thing in the absence of symptoms is that it is not always possible to diagnose presentation on time.

In some cases, placenta previa makes itself felt bleeding. This means that there was a premature detachment of the placenta. Actually, this is precisely the main danger of presentation, although not the only one.

As you remember, the placenta supplies the fetus with nutrients and oxygen. When the placenta is located low, and even more so blocks the exit from the uterus, it turns out that the child presses on it with all its weight. It can compress blood vessels in the placenta. This, in turn, can cause oxygen starvation - hypoxia.

As the fetus grows, the pressure on the placenta increases, in addition, the movements of the child become more active, it touches the placenta. As a result, premature placental abruption. In this case, the consequences can be deplorable not only for the child, but also for the mother. Especially if she has problems with blood clotting.

Bleeding during presentation can occur as early as the second trimester, immediately after the formation of the placenta. However, most often it occurs at a later date, sometimes just before childbirth, or even during childbirth.

Therefore, if a symptom of placenta previa becomes vaginal bleeding, it is necessary to urgently consult a doctor to establish the cause and begin treatment.

Separately, it is worth talking about childbirth during presentation. Full presentation, a condition when the placenta blocks the exit from the uterus, completely excludes the possibility of natural childbirth.

Placental tissue simply will not release the fetus into the birth canal. But in the case of partial presentation, natural childbirth, in principle, is possible. The main thing is that the doctors who take delivery carefully monitor the woman in labor. In the event of bleeding, it still makes sense to perform an emergency caesarean section.

Diagnosis of anterior presentation

Placenta previa can be diagnosed in several ways. Including when gynecological examination. Full and partial presentation by palpation are felt differently. With full presentation, it is felt to the touch that the cervix of the uterus is completely blocked by the placenta.

With partial presentation, both placental tissue and fetal membranes are felt. By the way, when viewed from the side and marginal presentation are perceived equally. So the gynecologist, without additional devices, will not be able to determine what kind of partial presentation in question.

If a woman was initially diagnosed with low placentation, for example, during the first planned ultrasound, then later she will be regularly examined, including with the help of ultrasound. Then, in the case of placental migration and the development of presentation, this will be detected in a timely manner during the next study. Ultrasound will show the presence of pathology even if it is asymptomatic. That is why women are advised to attend all routine examinations and ultrasound examinations.

Treatment of women with anterior presentation

Unfortunately, modern medicine is not able to influence the location of the placenta. Treatment of placenta previa comes down to the constant supervision of doctors and timely examinations. In this case, not only the condition of the fetus and placenta, but also the pregnant woman is monitored. Be sure to do a blood test regularly. The level of hemoglobin and the ability of the blood to clot are checked. The fact is that anemia or acute blood incoagulability can play a bad joke on the expectant mother in case of bleeding.

If, for a period of more than 24 weeks, a woman diagnosed with anterior placenta previa opens vaginal bleeding, no matter how severe it is, the woman is hospitalized. And be sure to go to the hospital where there is a special resuscitation unit. In case of extensive blood loss. The main and first appointment for all women with bleeding during pregnancy is absolute peace.

How does the lower placenta previa affect the course of pregnancy and childbirth, what danger does such a diagnosis pose for the expectant mother and baby. The answers to these questions are easy to get by reading the article.

• Placenta previa is a term used in obstetric and gynecological practice to refer to the location of the placenta in the uterine cavity.
• Presentation can pose a high risk of complications during childbirth for the woman and the newborn. With normal intrauterine development, placental tissue is attached along the back wall, sometimes with a transition to the side walls of the uterine cavity
• Cases when the placental tissue is displaced into the lower segments of the uterus and attached in the cervical region, thereby completely or partially closing the entrance to the birth canal for the fetus, are serious pathologies of pregnancy.

Classification of presentation forms

Depending on the actual place of attachment of the placenta, several types and forms of presentation are classified, representing a more or less dangerous situation in childbirth.

The doctor can determine the physiological characteristics and the possible threat of termination of pregnancy, as well as the risk of complications in labor activity, based on the data of the recommended planned ultrasound examination.

Particular cases of placenta previa

Complete placenta previa

There is a dense overlap of the placental tissue of the internal os of the uterus. During childbirth, this will not allow the fetus to pass through the birth canal, even if the cervix is ​​fully dilated, so normal childbirth becomes contraindicated.

Central placenta previa

The opening of the entrance of the cervical canal is completely blocked by the main part of the placenta. With a local vaginal examination by palpation, it is impossible to feel the fetal membranes, since they are covered with placental tissue.

Such a diagnosis is also a severe pathology and excludes the possibility of normal delivery.

Lateral placenta previa

The main part of the placental tissue is located to the right or left of the internal os. In such a situation, the doctor must determine the size of the area that overlaps the opening of the cervical canal. This case refers to an incomplete presentation.

Marginal placenta previa

In the process of vaginal examination, the fetal membranes that are in close proximity to the edge of the opening of the cervical canal are probed. The placenta is fixed along the very edge of the internal os.

Forms of placenta previa

Posterior placenta previa

Such a location refers to cases of incomplete presentation, when the main part of the placental tissue is located in the posterior segment with an offset to the bottom.

Anterior placenta previa

The formation of placental tissue along the anterior segment is not considered a pathology. Variants of anterior and posterior presentation correspond to the norm until the 25th-27th week of gestation.

Over the next 6-8 weeks, along with the active intrauterine growth of the child and the walls of the cavity, the placenta may shift, and by the time labor begins, there will be no risk of complications.

What does low placenta previa mean?

Low presentation is the situation when the placenta is fixed at a small distance (less than 3 cm) from the entrance to the cervical canal and does not close it.

In such a structure, conventional childbirth is quite feasible in the absence of other risks. With further observation, 2 options for the development of the situation are possible:

• moving the placenta up along with the growing walls and the possibility of normal delivery
• downward displacement - then there is a case of partial or absolute overlap of the birth canal, so the need for obstetric care, as well as the degree of risk of natural childbirth, should be assessed by the attending physician

Low placenta previa

Low posterior placenta previa

This is a special case of inferior presentation, when the placenta is located in the lower segment, but the main part of the placental tissue is located along the back wall.

Low marginal placenta previa

It is also one of the options for lower presentation with placement along the edge of the internal pharynx.

The tasks of an ultrasound scan performed at the 36-37th week of pregnancy include clarifying the actual degree of presentation, i.e. assessment of the amount of overlap and the development of pathology:

• Grade 1 - the placenta is located near the internal opening of the cervix, but distally displaced from it by at least 3 cm
• Grade 2 - the lower part is fixed near the very edge of the entrance to the cervical canal, but does not close it
• Grade 3 - part of the placenta partially or completely covers the internal os of the uterus. In this case, the main part of the placental tissue is displaced along the anterior or posterior wall
• Grade 4 - the placenta is entirely located in the lower segment and tightly blocks the entrance to the cervical canal with its main part

Ultrasound examination in the second half of pregnancy

As a rule, diagnosing the 3rd or 4th degree of pathology involves surgical intervention during obstetrics (planned caesarean section) to exclude injuries and death of the newborn and the woman in labor.

Causes of low placenta previa

The primary formation and further growth of the placenta is observed in the segment of the uterine cavity where the fetal egg was originally attached. The causes of fixation in the lower region are conditionally divided into 2 groups.

From the mother-to-be:

• Acquired changes in the structure of the uterine mucosa, formed as a result of inflammatory diseases of various nature - endometriosis, endometritis, adnexitis, parametritis, salpingitis, endocervicitis
• Mechanical damage to the endometrium - abortion, curettage, complicated childbirth, surgical interventions
• Physiological features, including acquired changes in the structure of the uterus or the presence of various formations - underdevelopment of the internal genital organs, trauma to the pelvic area, bending of the uterus, fibroids, cysts
• Diseases of the heart, liver and kidneys, leading to the formation of congestive processes in the pelvic area and internal genital organs
• Hormonal disorders that lead to disruptions in menstrual function - an irregular cycle, heavy menstrual flow, severe pain

From the side of the fetus:

Reducing the activity of enzymes in the development of the membranes of the fetal egg due to internal processes. As a result, a fertilized egg, moving in the cavity, cannot be implanted in the side walls of the uterus and is fixed in the lower sections.

Low placenta previa during pregnancy: symptoms

• The main symptoms that signal low presentation are repetitive, intense or scanty spotting, often not accompanied by painful sensations.
• Bleeding is external, without the formation of hematomas in the cavity, may appear for no specific reason already in the early stages, starting from the 12-14th week and continuing until the moment of delivery
• More often these symptoms are observed in the 2nd half of gestation (28-32 weeks) and intensify towards the end of the third trimester. The intensity and frequency of bleeding do not depend on the degree and form of presentation, but are associated with the physiological structure of the tissue

Bleeding with low placenta previa

• The cause of spotting is a partial detachment of small areas of the placenta as the walls of the uterus stretch.
• Unfavorable external factors can provoke bleeding - heavy physical exertion, overwork, stressful conditions, gynecological examination, sexual intercourse, hypothermia, long trips, visiting a bath
• Indirect symptoms of low presentation are incorrect intrauterine position of the fetus, displacement of the uterine fundus

What threatens low placenta previa during pregnancy?

Diagnosis of low presentation may mean the development of concomitant complications during pregnancy:

• Threat of miscarriage - due to periodic cases of partial detachment of placental tissue, which leads to increased uterine tone, recurrent bleeding and malnutrition of the fetus
• Anemia and hypotension (low blood pressure) - develop as a result of regular bleeding, cause weakness, headaches, dizziness, fatigue
• Incorrect presentation of the fetus - due to insufficient space in the lower uterus for the location of the baby's head
• Hypoxia and the likelihood of fetal growth retardation - the weakening of blood flow in the tissues of the placenta reduces the supply of sufficient oxygen and essential nutrients to the child, which causes chronic fetal hypoxia and affects its proper development and growth

Deterioration of the condition of a pregnant woman in case of a low location of the placenta

Low placenta previa during childbirth

In the case of diagnosing a low presentation, the expectant mother should be under the constant supervision of specialists.

Childbirth can take place both naturally and with the help of surgical intervention. The choice of the method of obstetrics is determined by the attending physicians and depends on the general condition of the woman, the degree of presentation, the location of the fetus at the time of delivery, the presence of bleeding, and other related factors.

Planned caesarean section is performed in 75-85% of cases of lower presentation for a period of 38 weeks.

Spontaneous childbirth in such a situation is extremely dangerous, since complete detachment of the placenta can cause profuse bleeding, up to the likelihood of death for the woman in labor and the fetus.

Caesarean section with low placenta previa

Direct indications for the operation are:

• Complete low placenta previa
• Breech or foot presentation of the fetus
• Scar on the uterus after surgery
• Multiple or late pregnancy
• Aggravated history - inflammatory diseases, abortions, fibroids or polycystic uterus
• Incessant heavy bleeding with a blood loss of more than 200 ml

If there are no indications for a caesarean section, then in the presence of active labor, a normal birth is performed. In the event of bleeding, the obstetrician must decide on an emergency caesarean section.

Sex and low placenta previa

Sexual intercourse and sexual games in the case of lower presentation are strictly contraindicated, since any physical pressure, as well as sexual arousal, can provoke intense contraction of the muscles of the uterus, partial or complete abruption of the placenta, bleeding and the threat of termination of pregnancy.

Low placenta previa during pregnancy: treatment

There is no type of therapy that can affect the actual location of the placenta. Therefore, the treatment of a woman consists in constant monitoring, timely relief of the intensity of blood secretions and the preservation of the fetus.

Mandatory medical supervision of a pregnant woman

Any physical and psycho-emotional stress, as well as other conditions that can cause bleeding and lead to miscarriage, are contraindicated for the expectant mother. During rest, you need to take a pose, lying on your back, slightly raising your legs up.

Particular attention should be paid to proper nutrition, timely conduct of the necessary clinical studies and analyzes.

Starting from the 2nd trimester of pregnancy, treatment consists of taking the following drugs:

• to improve the elasticity of the walls of the uterus, relieve spasms and increased tone - Drotaverine, Papaverine, Ginipral
• to prevent the development of iron deficiency - Aktiferrin, Hemohelper, Ferlatum, Hemofer, etc.
• to enhance blood circulation and nutrition of the placental tissue and the fetus - Curantil, Actovegin, folic acid, vitamin E, Magne B6

Video: Is a low placenta normal?

- 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, subject to the normal condition of the woman and the fetus.

General information

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 concomitant diseases of the internal organs, in particular, in the pathology of the cardiovascular system. Due to insufficient blood circulation and congestion in the 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 the physical activity of the woman, the movements of the baby, against the background of a strong stretching 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 symptom 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 is characterized by 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. The appearance of this symptom is possible even during a 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 such 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 combined with an abnormal position of the fetus, which can be oblique or transverse.

A preliminary diagnosis is established on the basis of the patient's complaints of spotting in the absence of pain. Another characteristic sign of the abnormal location of the embryonic organ is the 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 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, careful monitoring in the hospital is required. 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 is carried out. 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 the case of a full-term pregnancy, vaginal delivery is acceptable provided that the cervix is ​​ripe, labor is active, the patient and fetus are in good condition. 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. With timely diagnosis and compliance with medical recommendations, patients manage to carry the fetus up to 38 weeks and give birth to a completely healthy baby. 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 consists in the treatment of gynecological diseases even before conception, the exclusion of abortions 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.

The placenta is laid at the very beginning of pregnancy and is fully formed by 16 weeks. It provides nutrition to the fetus, excretion of metabolic products, and also performs the function of the lungs for it, because. it is through the placenta that the fetus receives the oxygen necessary for its life. In addition, the placenta is a real "hormonal factory": hormones are formed here that ensure the preservation, normal development of pregnancy, growth and development of the fetus.

The placenta consists of villi - structures, inside which the vessels pass. As pregnancy progresses, the number of villi, and, accordingly, the number of blood vessels is constantly growing.

Location of the placenta: norm and pathology

From the side of the uterus at the site of attachment of the placenta there is a thickening of the inner membrane. Deepenings are formed in it, which form the intervillous space. Some villi of the placenta fuse with the maternal tissues (they are called anchors), while the rest are immersed in the maternal blood that fills the intervillous space. Anchor villi of the placenta are attached to the partitions of the intervillous spaces, vessels pass through the thickness of the partitions, which carry maternal arterial blood saturated with oxygen and nutrients.

The villi of the placenta secrete special substances - enzymes that "melt" small arterial vessels that carry maternal blood, as a result of which blood flows out of them into the intervillous space. It is here that the exchange between the blood of the fetus and the mother takes place: with the help of complex mechanisms, oxygen and nutrients enter the fetal blood, and the fetal metabolic products enter the mother's blood. The fetus is connected to the placenta by the umbilical cord. One end is attached to the umbilical region of the fetus, the other - to the placenta. Inside the umbilical cord are two arteries and a vein that carry blood, respectively, from the fetus to the placenta and vice versa. Blood rich in oxygen and nutrients flows through the vein of the umbilical cord to the fetus, and venous blood from the fetus, containing carbon dioxide and metabolic products, flows through the arteries.

Normally, the placenta is located closer to the bottom of the uterus along the anterior or, less often, its posterior wall. This is due to more favorable conditions for the development of the fetal egg in this area. The mechanism for choosing the place of attachment of the fetal egg is not completely clear: there is an opinion that the force of gravity plays a role in choosing a place - for example, if a woman sleeps on her right side, then the egg is attached to the right wall of the uterus. But this is just one of the theories. It can only be unequivocally said that the fetal egg does not attach to places that are unfavorable for this, for example, to the locations of myomatous nodes or to places of damage to the inner lining of the uterus as a result of previous curettage. Therefore, there are other options for the location of the placenta, in which the placenta is formed closer to the lower part of the uterus. Allocate a low location of the placenta and placenta previa.

They say about the low location of the placenta when its lower edge is at a distance of no more than 6 cm from the internal pharynx of the cervix. This diagnosis is established, as a rule, during ultrasound. Moreover, in the second trimester of pregnancy, the frequency of this pathology is approximately 10 times higher than in the third trimester. It's pretty easy to explain. Conventionally, this phenomenon is called the "migration" of the placenta. In fact, the following happens: the tissues of the lower part of the uterus, very elastic, with an increase in the duration of pregnancy, undergo significant stretching and stretch upwards. As a result of this, the lower edge of the placenta seems to move upward, and as a result, the location of the placenta becomes normal.

Placenta previa is a more serious diagnosis. In Latin, this condition is called placenta praevia. "Pre via" literally means before life. In other words, the term "placenta previa" means that the placenta is on the way to the emergence of a new life.

Placenta previa is complete or central, when the entire placenta is located in the lower part of the uterus and completely covers the internal cervical os. In addition, there is a partial placenta previa. It includes marginal and lateral presentation. Placenta previa is said to be when up to 2/3 of the uterine outlet is covered with placental tissue. With marginal placenta previa, no more than 1/3 of the opening is closed.

Causes of anomalies

The main cause of anomalies of placental attachment are changes in the inner wall of the uterus, as a result of which the process of attaching a fertilized egg is disrupted.

These changes are most often caused by an inflammatory process of the uterus that occurs against the background of curettage of the uterine cavity, abortion, or associated with sexually transmitted infections. In addition, deformity of the uterine cavity predisposes to the development of such a pathology of the placenta, due either to congenital anomalies in the development of this organ, or to acquired causes - uterine fibroids (benign tumor of the uterus).

Placenta previa can also occur in women suffering from serious diseases of the heart, liver and kidneys, as a result of congestion in the pelvic organs, including in the uterus. That is, as a result of these diseases, areas with worse blood supply conditions than other areas appear in the wall of the uterus.

Placenta previa in multiparous women occurs almost three times more often than in women carrying their first child. This can be explained by the "baggage of diseases", including gynecological ones, which a woman acquires by the age of the second birth.

There is an opinion that this pathology of the location of the placenta may be associated with a violation of some functions of the fetal egg itself, as a result of which it cannot attach itself to the most favorable part of the uterus for development and begins to develop in its lower segment.

Quite often, placenta previa can be combined with its dense attachment, as a result of which the independent separation of the placenta after childbirth is difficult.

It should be noted that the diagnosis of placenta previa, with the exception of its central variant, will be quite correct only closer to childbirth, because. the position of the placenta may change. This is all due to the same phenomenon of “migration” of the placenta, due to which, when the lower segment of the uterus is stretched at the end of pregnancy and during childbirth, the placenta can move away from the area of ​​\u200b\u200bthe internal os and not interfere with normal childbirth.

Beware of bleeding!

Bleeding with placenta previa has its own characteristics. It is always external, i.e. blood flows out through the cervical canal, and does not accumulate between the wall of the uterus and the placenta in the form of a hematoma.

Such bleeding always begins suddenly, as a rule, without any apparent external cause, and is not accompanied by any pain. This distinguishes them from bleeding associated with premature termination of pregnancy, when, along with spotting, there are always cramping pains.

Often bleeding begins at rest, at night (woke up "in a pool of blood"). Once having arisen, bleeding always repeats, with greater or lesser frequency. Moreover, it is never possible to foresee in advance what the next bleeding will be in terms of strength and duration.

After 26-28 weeks of pregnancy, such bleeding can be triggered by physical activity, sexual intercourse, any increase in intra-abdominal pressure (even coughing, straining, and sometimes a gynecologist's examination). In this regard, examination on the chair of a woman with placenta previa should be carried out with all precautions in a hospital, where emergency assistance can be provided in case of bleeding. The bleeding itself is dangerous for the life of mother and baby.

Symptoms and possible complications

The main complications and the only manifestations of placenta previa are spotting. Depending on the type of presentation, bleeding may occur for the first time during various periods of pregnancy or in childbirth. So, with central (complete) placenta previa, bleeding often begins early - in the second trimester of pregnancy; with lateral and marginal options - in the third trimester or directly in childbirth. The amount of bleeding also depends on the type of presentation. With a complete presentation, bleeding is usually more abundant than with an incomplete version.

Most often, bleeding occurs at a gestational age of 28-32 weeks, when the preparatory activity of the lower uterine segment is most pronounced. But every fifth pregnant woman with a diagnosis of placenta previa notes the appearance of bleeding in the early stages (16-28 weeks of pregnancy).

What causes bleeding in placenta previa? During pregnancy, the size of the uterus constantly increases. Before pregnancy, they are comparable to the size of a matchbox, and by the end of pregnancy, the weight of the uterus reaches 1000 g, and its dimensions correspond to the size of the fetus along with the placenta, amniotic fluid and membranes. Such an increase is achieved, mainly due to an increase in the volume of each fiber that forms the wall of the uterus. But the maximum change in size occurs in the lower segment of the uterus, which stretches the more, the closer the term of delivery. Therefore, if the placenta is located in this area, then the process of "migration" is very fast, the low-elastic tissue of the placenta does not have time to adapt to the rapidly changing size of the underlying uterine wall, and placental abruption occurs over a greater or lesser extent. In the place of detachment, damage to the vessels occurs and, accordingly, bleeding.

With placenta previa, the threat of abortion is often noted: increased uterine tone, pain in the lower abdomen and in the lumbar region. Often, with this location of the placenta, pregnant women suffer from hypotension - stably reduced pressure. A decrease in pressure, in turn, reduces performance, causes weakness, feelings of weakness, increases the likelihood of fainting, the appearance of a headache.

In the presence of bleeding, anemia is often detected - a decrease in the level of hemoglobin in the blood. Anemia can exacerbate the symptoms of hypotension, in addition, oxygen deficiency caused by a decrease in hemoglobin levels adversely affects the development of the fetus. There may be growth retardation, fetal growth retardation syndrome (FGR). In addition, it has been proven that children born to mothers who suffered from anemia during pregnancy always have a reduced hemoglobin level in the first year of life. And this, in turn, reduces the defenses of the baby's body and leads to frequent infectious diseases.

Due to the fact that the placenta is located in the lower segment of the uterus, the fetus often takes the wrong position - transverse or oblique. Often there is also a breech presentation of the fetus, when its buttocks or legs are turned towards the exit from the uterus, and not the head, as usual. All this makes it difficult or even impossible to have a child naturally, without surgery.

Diagnostics

Diagnosis of this pathology is most often not difficult. It is usually established in the second trimester of pregnancy based on complaints of intermittent bleeding without pain.

The doctor on examination or during an ultrasound scan may reveal an incorrect position of the fetus in the uterus. In addition, due to the low location of the placenta, the underlying part of the child cannot descend into the lower part of the uterus, therefore, a high standing of the presenting part of the child above the entrance to the small pelvis is also a characteristic feature. Of course, modern doctors are in a much more advantageous position compared to their counterparts 20-30 years ago. At that time, obstetrician-gynecologists had to navigate only by these signs. After the introduction of ultrasound diagnostics into wide practice, the task has become much simpler. This method is objective and safe; Ultrasound allows you to get an idea of ​​the location and movement of the placenta with a high degree of accuracy. For these purposes, it is advisable to triple ultrasound control at 16, 24-26 and 34-36 weeks. If, according to the ultrasound examination, no pathology of the location of the placenta is detected, the doctor may, during examination, identify other causes of spotting. They can be various pathological processes in the vagina and cervix.

Observation and treatment

An expectant mother who has been diagnosed with placenta previa needs careful medical supervision. Of particular importance is the timely conduct of clinical trials. If even a slightly reduced level of hemoglobin or disorders in the blood coagulation system are detected, the woman is prescribed iron supplements, because. in this case, there is always a risk of rapid development of anemia and bleeding. If any, even minor, deviations in the state of health are detected, consultations of the relevant specialists are necessary.

Placenta previa is a formidable pathology, one of the main causes of serious obstetric bleeding. Therefore, in the event of bleeding, all a woman’s health problems, even small ones, can aggravate her condition and lead to adverse consequences.

In the presence of bloody discharge, observation and treatment of pregnant women with placenta previa at gestational ages over 24 weeks is carried out only in obstetric hospitals that have conditions for providing emergency care in an intensive care unit. Even if the bleeding has stopped, the pregnant woman remains under the supervision of the hospital doctors until the due date.

In this case, treatment is carried out depending on the strength and duration of bleeding, the duration of pregnancy, the general condition of the woman and the fetus. If the bleeding is insignificant, the pregnancy is premature and the woman feels well, conservative treatment is performed. Strict bed rest, drugs to reduce the tone of the uterus, improve blood circulation are prescribed. In the presence of anemia, a woman takes drugs that increase the level of hemoglobin, general strengthening drugs. Calming agents are used to reduce emotional stress.

regime plus diet

If there is no bleeding, especially with a partial variant of placenta previa, a woman can be observed on an outpatient basis.

In the diet, there must be foods rich in iron: buckwheat, beef, apples, etc. Be sure to have a sufficient protein content, because. without it, even with a large intake of iron, hemoglobin will remain low: in the absence of protein, iron is poorly absorbed. It is useful to regularly eat vegetables and fruits rich in fiber, because. stool retention can provoke the appearance of spotting. Laxatives for placenta previa are contraindicated. Like all pregnant women, patients with placenta previa are prescribed special multivitamin preparations. If all these conditions are met, the manifestations of all the symptoms described above, which in most cases accompany placenta previa, are reduced, which means that conditions are provided for the normal growth and development of the child. In addition, in the event of bleeding, the adaptive capabilities of the woman's body increase, and blood loss is more easily tolerated.

childbirth

With complete placenta previa, even in the absence of bleeding, a caesarean section is performed at 38 weeks of gestation, because. spontaneous childbirth in this case is impossible. The placenta is located on the way the baby leaves the uterus, and if you try to give birth on your own, it will completely detach with the development of very severe bleeding, which threatens the death of both the fetus and the mother.

The operation is also resorted to at any stage of pregnancy in the presence of the following conditions:

Placenta previa, accompanied by significant bleeding, life-threatening;

Recurrent bleeding with anemia and severe hypotension, which are not eliminated by the appointment of special drugs and are combined with a violation of the fetus.

In a planned manner, a caesarean section is performed at a period of 38 weeks with a combination of partial placenta previa with another pathology, even in the absence of bleeding.

If a pregnant woman with partial placenta previa carried the pregnancy to term, in the absence of significant bleeding, it is possible that childbirth will occur naturally. With the opening of the cervix by 5-6 cm, the doctor will finally determine the variant of placenta previa. With a small partial presentation and slight bleeding, an opening of the fetal bladder is performed. After this manipulation, the fetal head descends and compresses the bleeding vessels. The bleeding stops. In this case, the completion of childbirth in a natural way is possible. With the ineffectiveness of the measures taken, childbirth is completed promptly.

Unfortunately, after the birth of a child, the risk of bleeding remains. This is due to a decrease in the contractility of the tissues of the lower segment of the uterus, where the placenta was located, as well as the presence of hypotension and anemia, which have already been mentioned above. In addition, it has already been said about the frequent combination of presentation and dense attachment of the placenta. In this case, the placenta after childbirth cannot completely separate from the walls of the uterus on its own and it is necessary to conduct a manual examination of the uterus and separation of the placenta (the manipulation is performed under general anesthesia). Therefore, after childbirth, women who had placenta previa remain under the close supervision of hospital doctors and must carefully follow all their recommendations.

Infrequently, but still there are cases when, despite all the efforts of doctors and a caesarean section, the bleeding does not stop. In this case, it is necessary to resort to the removal of the uterus. Sometimes this is the only way to save a woman's life.

Precautionary measures

It should also be noted that with placenta previa, one should always keep in mind the possibility of developing severe bleeding. Therefore, it is necessary to discuss with the doctor in advance what to do in this case, which hospital to go to. Staying at home, even if the bleeding is light, is dangerous. If there is no prior agreement, you need to go to the nearest maternity hospital. In addition, with placenta previa, you often have to resort to blood transfusions, so if you have been diagnosed with such a diagnosis, find out in advance which of your relatives has the same blood type as you and get their consent to donate blood for you if necessary (the relative must pre-test for HIV, syphilis, hepatitis).

You can arrange in a hospital where you will be observed so that your relatives donate blood for you in advance. At the same time, it is necessary to enlist a guarantee that the blood is used specifically for you - and only if you do not need it, it will be transferred to a general blood bank. It would be ideal for you to donate blood for yourself, but this is only possible if your condition does not cause concern, all indicators are normal and there is no spotting. You can donate blood for storage multiple times during your pregnancy, but you also need to ensure that your blood is not used without your knowledge.

Although placenta previa is a serious diagnosis, modern medicine allows you to endure and give birth to a healthy child, but only if this complication is diagnosed in a timely manner and all doctor's prescriptions are strictly observed.

When everything is over and you and your baby are at home, try to organize your life properly. Try to rest more, eat right, be sure to walk with the baby. Do not forget about multivitamins and drugs for the treatment of anemia. If possible, do not refuse breastfeeding. This will not only lay the foundation for the health of the baby, but also speed up the recovery of your body, because. stimulation of the nipple by sucking causes the uterus to contract, reducing the risk of postpartum hemorrhage and uterine inflammation. It is desirable that at first someone helps you in caring for the child and household chores, because your body has suffered a difficult pregnancy, and it needs to recover.

The slightest changes in well-being during pregnancy cause concern. As a rule, a visit to the doctor immediately follows with the hope of hearing that there is no reason to worry and this is a false alarm and the suspiciousness inherent in all pregnant women is to blame. And suddenly it turns out that the fears were not in vain, and the diagnosis “marginal placenta previa” sounds. Instead of starting to panic and drive yourself crazy, you need to calm down, pull yourself together and figure out what it is and how dangerous it is.

The placenta is a unique and complex formation that appears in a woman's body at the moment when a fertilized egg attaches to the wall of the uterus. Like any living organism, it goes through all stages of life: appearance, maturation and aging. The life of a small creature that settled inside the mother's tummy depends on it. Through it, the baby breathes and receives nutrition. No wonder it is also called the "children's place." It serves as a kind of filter that supplies oxygen to the fetus, and removes carbon dioxide and metabolic products back. Through it, antibodies from the mother to the baby come, which perform immune protection. Without it, the same mother's antibodies would have recognized the child as a foreign body and provoked rejection.

The active development of the placenta begins from the 9-10th week. On the 12th child completely switches to placental nutrition and receives the official name "fetus". And by the 15-16th week, it is already, as a rule, a fully formed organ that will grow with the baby throughout the pregnancy. During planned ultrasounds, they monitor not only the development of the fetus, but also the condition, location and maturity of this vital “cake”.

In the normal course of pregnancy, the placenta is located on the back or front wall of the uterus at a distance from the uterine os. The most optimal and most common is the posterior attachment. With it, blood circulation is best, and the place itself is less prone to various injuries. But sometimes it is closer to the exit than it should be, or completely blocks it. This is called presentation, which, respectively, is complete (central) or incomplete.

The most dangerous is a complete presentation. With it, the birth canal is completely blocked, as a result of which the child can be born exclusively by caesarean section.

With incomplete presentation, the placenta is in the lower segment and partially blocks the exit from the uterus to the cervix. There are two types: lateral presentation, in which the pharynx overlaps by two-thirds, and marginal, when the lower part of the placenta hangs over the exit and obscures it by no more than a third.

Marginal placenta previa, in turn, occurs along the posterior and anterior walls, and has different prognosis depending on the location:

• On the front wall, on the one hand, is the most dangerous. With it, placental abruption occurs more often. The reason for this is that the placental tissue is not able to stretch as quickly as the uterine tissue. Simply put, it does not have time to grow behind it, and the risk of detachment of the hanging edge increases. In addition, this is aggravated by the active movements of the child, the physical activity of the mother. But, on the other hand, with such a marginal presentation, there is a high chance that with the growth of the uterus, the placenta will rise to a safe distance.
• Along the back wall occurs more frequently and poses less of a threat than in the previous case. This is due to the fact that this part has less load. With him, there is every chance to calmly endure the pregnancy and give birth on her own.

In fact, in the world from this pathology, 3-25% of pregnancies end tragically, or the baby is born with some deviations. Therefore, you need to take the regional and other types seriously, regularly monitor the dynamics and follow all the doctor's recommendations.

Causes of marginal placenta previa

One of the factors of such a pathology is the peculiarity of the fetal egg. After fertilization, the egg descends into the uterus and with its villi is attached to its wall in the upper part. Due to the hormonal background or the structure of the villi, this does not happen. The egg is unable to reach the bottom of the uterus and clings to the exit.

The main reason for the marginal attachment of the placenta is the female body, or rather the state of the mucous surface or endometrium of the main reproductive organ.

Factors that violate the integrity of the endometrium and cause presentation, including marginal, are:

• inflammation, ;
• underdevelopment of the uterus;
• repeated pregnancy;
• endometriosis, endocervicitis;
• genital infections;
• age over 35;
• scars after an abortion or curettage;
• operations on the uterus;
• and other benign tumors;
• congenital pathologies;
• diseases of the cardiovascular system;
• diseases of the pelvic organs.

In re-children, this anomaly is observed in 55% of cases, that is, almost every second. But in general, according to observations, the diagnosis of the marginal location is heard by a third of expectant mothers.

As a rule, they appear at the end of the second or third trimesters from 28 to 32 weeks. At this time, there is an active growth of the uterus. The placental tissue does not have time to stretch and marginal detachment occurs, which is accompanied by bleeding. The larger the detached area, the more intense they are. This can happen at an earlier date with or multiple pregnancies.

Any stress can cause detachment. This can happen with intra-abdominal pressure, which is often found in pregnant women, during passionate intercourse, and even with a banal raising of hands. An active baby with his movements can also contribute to this. Often a woman herself serves as a provocateur when she lifts weights or during overly active physical exertion. Bloody discharge can also appear during a visit to the sauna or taking a hot bath.

Bleeding begins suddenly, without pain syndromes, and also suddenly stops. At the same time, it is impossible to predict when this will happen next time and how plentiful they will be.

This pathology is sometimes noticed already at the first planned ultrasound at the 12-13th week or in the second trimester. As a rule, nothing bothers a woman, and such a diagnosis sounds very unexpected for her. But most often, a pregnant woman herself comes to the doctor with complaints of blood discharge or bleeding. After a thorough examination, a conclusion is made about the marginal or complete presentation, and the type of abnormal location and the degree of its danger to the fetus and expectant mother are determined. Given the complexity and risk of complications, in most cases a woman is recommended to go to a hospital to monitor her condition and complete examination.

What complications can occur with marginal placenta previa?

Due to the fact that when the placenta is detached during the marginal location, the vessels are damaged, the child does not receive the necessary nutrition and oxygen. This is called fetal hypoxia. It threatens with a developmental delay and such consequences for the mother and child as:

• incorrect location of the fetus;
• — low level of hemoglobin — from lack of iron in the body;
• hypotension and, as a result, weakness, and fainting;
• profuse bleeding during childbirth.
• risk of miscarriage;

First of all, it is complete physical and psychological rest. Not all mothers manage to achieve this at home. Not everyone can afford not to go to work. And that is where the greatest emotional stress occurs. When there is a strong recommendation to lie down for preservation, the majority immediately panics with thoughts about who will work instead of me, as well as wash and clean. Trust me, the world won't stop without you. Your main task at the moment is not to submit an accounting report or walk your beloved dog, but to endure and give birth to a healthy, long-awaited baby.

Mom is assigned strict bed rest, an iron-rich diet and, if necessary, drugs that improve blood circulation, reduce uterine tone and "increase hemoglobin". Up to 24 weeks, if there is no bleeding and the general condition does not bother, then it is allowed to be treated on an outpatient basis, while strictly following the recommendations and protecting yourself from household duties as much as possible. In difficult situations and at a later date, the mother can be in the clinic until the very birth, and sometimes mostly in the supine position.

The placenta begins to migrate from the end of the second trimester along with the growing tummy. Therefore, after the 26th week, there is a high chance that the marginal presentation will return to normal on its own.

With all the complexity of the diagnosis, in some cases a woman is still allowed to give birth on her own, but only with a slight presentation. The main conditions for this are a good labor activity, a mature cervix and the head location of the fetus. When the neck is opened by more than 4 cm or a finger, the degree of location of the organ is determined and the amniotic sac is opened and further childbirth proceeds naturally. If after opening the bleeding does not stop, then an emergency caesarean section is performed. Most often, doctors prefer not to take risks and, with a marginal location of any stage, they perform surgical delivery. As planned, this happens at 38-39 weeks, when the baby is fully formed and ready to be born.

With a strong or complete presentation

During natural childbirth, there is a high risk of placental abruption, which is fraught with profuse blood loss and other consequences for both the mother and the fetus, up to death. Therefore, it is better not to take risks and entrust your life and the life of the crumbs to experienced professionals.

What precautions should be taken by pregnant women with marginal placenta previa

Such a diagnosis is not a sentence, and with it it is quite possible to endure pregnancy and become a happy mother of a newborn miracle. For this you need:

• do not miss scheduled clinic visits;
• seek help at the slightest deterioration in the condition or the appearance of new symptoms, such as a sharp pain in the abdomen, and so on;
• immediately call an ambulance in case of bleeding;
• just in case, find in advance for yourself several people of your blood type who can become donors for you;
• forget about sex for a while;
• more rest and walk, if this is not prohibited by the doctor;
• sleep for 8 hours;
• follow a diet and do not consume soda and foods that provoke gas formation;
• protect yourself from negative emotions and stressful situations;
• follow all the recommendations of the attending physician;
• exclude all physical activity: fitness, weight lifting and even cleaning the house or apartment;

And the most important thing is to enjoy your “interesting position” and believe that everything will be fine!

Video

Watch the video from which you will learn what presentation is, what other types there are other than marginal, and how it affects the course of pregnancy.

Often, a diagnosis voiced by a doctor serves as an incentive to take a closer look at your health. Especially when you are responsible not only for your life, but also for a small miracle that grows inside you.