Oligohydramnios in later stages. What is oligohydramnios during pregnancy, its causes, and what is dangerous for the fetus and mother. Leakage of amniotic fluid

This is a decrease in the amount of amniotic fluid to 500 ml or less.

Causes of oligohydramnios during pregnancy

The reasons for this violation are not well understood. It is believed that oligohydramnios is associated with insufficient formation of amniotic fluid by the membranes or with their increased absorption by the placenta or membranes. Often, oligohydramnios is associated with malformations of the fetal kidneys, a form of their complete absence, and narrowing of the ureters.

Also of some importance is the disruption of blood flow in the placenta-fetus system.

Oligohydramnios negatively affects the course of pregnancy and fetal development. A small amount of water restricts the movements of the fetus, the forced position bends the spine, torticollis or clubfoot and other skeletal deformities are formed. With a small amount of water, the fetal skin touches the fetal membranes, which can form threads (cords) of fusion of areas of the fetal body with the fetal membranes. Such cords, during fetal movements, can lead to entanglement in the umbilical cord, squeeze fingers and limbs, sometimes even to the point of amputation, and cause circulatory disturbances in the fetus when the umbilical cord vessels are compressed.

The diagnosis is made by ultrasound, in dynamics. A pregnant woman with oligohydramnios is hospitalized in the maternity hospital, where treatment is carried out aimed at improving blood flow in the placenta and improving its nutritional function. Often, oligohydramnios is complicated by premature birth and placental abruption.

If oligohydramnios is diagnosed in combination with fetal malformations, then the pregnancy is terminated for medical reasons. If fetal growth is delayed, the outcome of pregnancy becomes problematic. In the third trimester, pregnancy is prolonged to 37 weeks and early delivery is carried out with careful monitoring of the fetal condition.

Severe oligohydramnios is characterized by a decrease in their quantity to 100 ml or less (in severe cases there may even be several milliliters of fluid in the amniotic space).

The reasons for the development of oligohydramnios are diverse, although, as with polyhydramnios, reliable causes have not been precisely established and have been little studied. Most often, this pathology is formed due to insufficient development of the amniotic epithelium (inner vesical membrane) or a decrease in its secretory (excretory) function. It is believed that a certain role in the occurrence belongs to the increased ability of the amnion (fetal bladder) to resorption (reabsorption) of amniotic fluid (scientific literature describes cases of complete disappearance of amniotic fluid, the amount of which was normal at the beginning of pregnancy). In itself, a decrease in water volume does not have pronounced detrimental consequences in the case when it does not last long and then is gradually restored to the proper level. However, along with a reduced amount of water, fetal growth retardation syndrome is more common. This is due to the fact that in a hypotrophic (low-weight) fetus, the normal functioning of the kidneys is naturally disrupted, and a decrease in hourly diuresis gradually leads to a decrease in the volume of amniotic fluid. Oligohydramnios is quite common in cases of development of identical twins, which is explained by the uneven distribution of blood circulating in the common placental apparatus between the two twins. These reasons are put forward as the most often assumed, however, along with them, the cause of oligohydramnios can be associated with various kinds of extragenital (outside the reproductive system) pathology of the mother (cardiovascular failure, disorders of the kidneys and liver).

When this kind of pathology appears, in most cases complications of pregnancy and labor occur, which ends in spontaneous miscarriage and premature birth.

The presence of oligohydramnios during pregnancy adversely affects the growth and development of the fetus, therefore this condition is classified as a painful condition and requires a full examination and treatment. Developmental disorders are a consequence of limited motor activity of the fetus due to insufficiency of amniotic fluid. Against this background, congenital clubfoot most often occurs, in some cases curvature of the spine and deformation of other skeletal bones. Often, with oligohydramnios, adhesions form between the child’s skin and the amnion. As the fetus further increases in size, they become elongated, and after delivery they take on the appearance of cords and threads. However, the possibility of the development of such strands against the background of an anomaly in the development of the ectoderm cannot be excluded. These formations sometimes cover the child’s torso and limbs, the umbilical cord, which causes disfigurement or even amputation of various parts of the body. Fetal death is possible as a result of compression of the umbilical cord. Fetal developmental defects are possible with oligohydramnios.

Primary oligohydramnios has a relatively favorable course, as it is not associated with a violation of the integrity of the amniotic membranes. Traumatic or secondary, a much less common form of this pathology, is characterized by damage to the membranes and gradual leakage of amniotic fluid during pregnancy. The discharge of amniotic fluid occurs through the gap formed between the membranes and the inner surface of the uterus. The size of the damage may vary, but, as a rule, its size is small and water leaks in small portions over a long period of time into the abdominal cavity (amnionic hydrorhea). The process of expiration of amniotic fluid can be either constant or periodic. In the case when the amniotic epithelium has the ability to synthesize, such an outflow of water is compensated for some time. Persistent cases of progression of oligohydramnios end in early termination of pregnancy.

A pregnant woman, with a decrease in the amount of water, may notice the appearance of pain in the uterine area. The pain is constant, aching, intensifying with fetal movements and with changes in body position of the pregnant woman herself. Initially, when the disease develops, its signs are slightly expressed; they become noticeable for a woman with the development of severe oligohydramnios and with the addition of fetal malformations (such children are inactive, the heartbeat is slow).

Diagnosis of oligohydramnios during pregnancy

The main diagnostic criterion for pathology is the determination of the discrepancy between the size of the uterus and the true gestational age. For diagnostic purposes, an ultrasound examination can be performed to help determine the exact amount of water, determine the gestational age based on the size of the fetus, identify the presence or absence of fetal malformations, determine its position in the uterus, and also perform a medical genetic examination by chorionic biopsy. This study involves taking material (blood from the umbilical cord or other vessels) under ultrasound control to determine the presence or predisposition to the development of genetic developmental abnormalities.

The course of oligohydramnios during pregnancy

The course of pregnancy with the development of oligohydramnios is characterized by frequent miscarriages - miscarriages in the early stages or premature births in later stages.

Childbirth in the presence of oligohydramnios also occurs with various kinds of complications. Prolonged labor is the most common. The opening of the uterine pharynx occurs extremely slowly. This situation is explained by the lack of proper functioning of the fetal bladder, which normally leads to adequate smoothing of the cervix and opening of the uterine pharynx. Contractions of the uterus are very painful and do not cause the desired reaction from the advancement of the fetus and, accordingly, the opening of the birth canal.

Consequences of oligohydramnios during pregnancy

One of the common complications of childbirth with oligohydramnios is premature abruption of a normally located placenta. This situation is dangerous for the development of bleeding, up to the death of the mother and fetus. A vaginal (transvaginal) examination during childbirth reveals the absence of tension in the membranes during contractions (flat membranes), while the membranes fit tightly to the presenting part of the fetus and only interfere with the normal course of the dilation period. Spontaneous rupture or artificial dilution of the membranes helps to accelerate the opening of the uterine pharynx and reduce the overall duration of labor. After opening the membranes, a small amount of turbid amniotic fluid is released (often mixed with meconium - fetal feces).

Oligohydramnios leads to adverse pregnancy outcomes, but the severity of the result depends on the stage of pregnancy at which AF pathology began. On the other hand, if oligohydramnios is the only finding in the third trimester, the outcome for the fetus is usually good. Because accurate ultrasound assessment of AFV has its limitations, care should be taken not to overuse the diagnosis of decreased amniotic fluid so that it does not lead to the inappropriate use of invasive interventions during pregnancy, such as early induction of labor. Despite this controversy, it is prudent to evaluate ultrasonographic evidence of decreased amniotic fluid to ensure that this is truly the only finding.

Fetal abnormalities/aneuploidy

Congenital anomalies and fetal aneuploidy are usually associated with oligohydramnios noticed in the second trimester. Most of the fetal anomalies occur in the genitourinary system; defects in the skeleton, central nervous system and cardiovascular system are also associated with oligohydramnios. It is important to remember that secondary oligohydramnios as a result of renal anomalies is not detected until 18 weeks of pregnancy, since maternal contribution to the formation of amniotic fluid remains high until 14-18 weeks. A comprehensive ultrasound assessment of the structure of the internal organs of the fetus, especially the kidneys and bladder, is necessary. Typically, transabdominal ultrasound can accurately diagnose renal agenesis, impaired outflow from the bladder, polycystic kidney dysplasia, and infantile polycystic kidney disease. In the absence of both kidneys and fluid in the fetal bladder, renal agenesis is diagnosed. For further examination of the fetus with renal agenesis, color Doppler sonography is used to determine the location of the renal arteries and identify the “lying” adrenal glands. Ultrasound picture of multicystic dysplastic kidneys and infantile polycystic kidney disease - enlarged hyperechoic or cystic kidneys. With obstruction of the bladder outlet associated with posterior urethral valve syndrome, an enlarged keyhole-shaped bladder and significantly dilated renal pelvis are identified. Due to severe oligohydramnios, accurate antenatal diagnosis of these fetal conditions using transabdominal ultrasound is sometimes difficult.

When visualization of fetal anatomy is poor at the beginning of the second trimester, transvaginal ultrasound is useful. Amnioinfusion has been proposed to improve ultrasound resolution, and the advent of MRI has made non-invasive confirmation of early ultrasound findings possible in most cases. In cases of severe oligohydramnios, it is difficult to perform amniocentesis to assess the fetal karyotype. The method of choice in this case is placental biopsy. With the exception of posterior urethral valve syndrome, where in some cases intrauterine surgery may improve outcome, the fetus is not viable due to pulmonary hypoplasia that develops in these conditions.

Rupture of membranes

Rupture of membranes is easily determined based on history and examination. During vaginal examination, sterile speculum is used to confirm the accumulation of amniotic fluid, determine the alkaline pH with nitrizine and identify the typical phenomenon of arborization. If the anamnesis and examination data are questionable, other methods are used for diagnosis. If, after amnioinfusion of indigo-carmine in Ringer's solution (100-150 ml), the vaginal tampon is stained, this indicates premature rupture of the membranes.

The use of methylene blue should be avoided as it may cause jejunal atresia in the fetus. After 22 weeks of pregnancy, fetal fibronectin is determined in the contents of the posterior fornix, although in uncomplicated pregnancy this test is not very informative. Its determination was used as a non-invasive method for confirming premature rupture of membranes with questionable results of anamnesis and clinical examination. The earlier the premature rupture of the membranes occurred, the more cautious the prognosis. A rupture with the onset of severe oligohydramnios before 24 weeks of pregnancy carries an additional risk of pulmonary hypoplasia, although not as pronounced as with fetal kidney anomalies. If amniotic fluid leaks after amniocentesis in the second trimester, the prognosis is quite good, survival rate is more than 90%.

Intrauterine growth restriction

Uteroplacental insufficiency leads to a redistribution of blood flow in the fetus in favor of vital organs. The patient's history and examination indicate risk factors for intrauterine growth restriction syndrome (IUGR) - drug addiction, chronic hypertension, previous obstetric history, birth weight of children and preeclampsia. Fetal biometry shows fetal weight below the 10th percentile. FGR, detected at the end of the second and third trimester, is characterized by asymmetry of the biometric parameters of the fetus (discrepancy between the head circumference and the abdominal circumference), while with severe FGR in the second trimester, symmetrical growth retardation is observed.

Ultrasound reveals premature maturation of the placenta (early placental calcification). Additional clues are provided by a Doppler study measuring blood flow velocity in the mother and fetus. Abnormal results of Doppler examination of the uterine artery at 18-24 weeks suggest placentation disorders and have some value in predicting adverse pregnancy outcomes. Doppler examination of the umbilical artery reveals an increase in placental resistance, noted with uteroplacental insufficiency. In the early stages of development of FGR, Doppler examination of the fetal middle cerebral artery reveals “brain steal syndrome” associated with redistribution of blood flow. It is expressed in an increase in diastolic blood flow velocity and a decrease in pulse index. Although there is no separate antenatal study to confirm FGR, pathological dynamic ultrasound results in combination with anamnesis allow one to calculate the prognosis and choose a rational treatment regimen.

Perinatal morbidity and mortality are inversely related to gestational age at diagnosis. In case of early onset severe FGR, the patient must be examined in detail in order to exclude fetal malformations.

Itrogenic causes

Many iatrogenic causes lead to oligohydramnios. These include fetal procedures - chorionic villus sampling or amniocentesis and taking various medications. A careful history can rule out these causes. NSAIDs and angiotensin-converting enzyme inhibitors reduce renal perfusion and lead to oligohydramnios. Fortunately, in most cases, oligohydramnios is reversible when you stop taking these medications.

Postmaturity

A decrease in the volume of amniotic fluid during post-term pregnancy is a reflection of uteroplacental insufficiency, which occurs in late pregnancy. In post-term pregnancy, it is recommended to monitor the volume of amniotic fluid and, if signs of oligohydramnios appear, induce labor. However, it is unclear whether these interventions lead to improved fetal outcomes.

Amniotic fluid is necessary to ensure normal intrauterine development of the fetus. For the future baby, it is a comfortable physiological environment, an additional source of nutrition and oxygen, and also a protective barrier that protects him from numerous external threats. In addition, amniotic fluid plays an important role in the process of childbirth, forcing the dilation of the cervix, as it is capable of exerting a mechanical effect on it.

Therefore, a relative lack of water can lead to various developmental disorders of the fetus and interfere with the normal course of pregnancy. Why is oligohydramnios dangerous? What are the different degrees of this condition, and what therapeutic method is most effective in this situation?

What is “moderate oligohydramnios”

Indicators of normal amniotic fluid volume vary depending on the specific stage of pregnancy. During the first 8 weeks this is approximately 5 ml. Next, the amount of fluid begins to increase, and by the end of pregnancy its total volume reaches an average of 1-1.5 liters. Immediately before birth, the water becomes smaller (their volume is approximately 600-700 ml).

The composition of amniotic fluid (from the word “amnion” - fetal sac) includes amino acids, vitamins, hormones, trace elements, some types of salts, enzymes, etc.

Amniotic fluid is formed due to the functioning of the epithelial layer of cells in the aqueous membrane of the amnion. They are constantly updated. At the extreme stages of pregnancy, this happens at least every 3 hours.

On average, per day the fetus has the ability to swallow 4 ml of amniotic fluid, and through the pores of the fetal sac, waste products enter the maternal excretory system. With a non-critical “shift” from normal levels of amniotic fluid volume (closer to the lower limit of normal), a pregnant woman is diagnosed with moderate oligohydramnios.

Causes

It happens that this condition is registered already in the initial stages of pregnancy. A similar diagnosis is made based on calculating the oligohydramnios index. In this case, the woman needs constant medical supervision and the use of certain methods of drug therapy.

The reasons for the formation of such a violation may be:

persistent hypertension (increased total blood pressure);
the presence in the body of a pregnant woman of any inflammatory process of an infectious nature;
fetoplacental insufficiency;
hypoxia (oxygen “starvation”) of the fetus;

diseases of a pregnant woman associated with metabolic disorders;
the presence of any pathologies in the fetus (underdevelopment of the excretory system will lead to a sharp decrease in the level of primary urine production, which leads to a reduction in the volume of amniotic fluid);
post-term pregnancy - the placenta can be reversed and therefore no longer has the ability to provide the fetus with all the necessary substances, including producing a sufficient volume of amniotic fluid;
multiple pregnancy - here there may be a disruption in the distribution of placental blood, which can also lead to water deficiency;
violation of secretion in epithelial cells of the aqueous membrane of the amnion.

Types of oligohydramnios

Based on the duration of the course, there are two types of oligohydramnios: acute and chronic.

Chronic oligohydramnios has several levels of development. This condition requires long-term therapy. If qualified assistance is not provided on time, the disease will worsen., which will lead to serious consequences for both the expectant mother and the child.

Chronic deficiency of amniotic fluid can occur if a pregnant woman suffers from a systemic disease, such as diabetes.

In order to minimize all possible risks and apply appropriate therapy in a timely manner, in case of oligohydramnios, a woman needs to register with the antenatal clinic as early as possible and regularly undergo all the necessary examinations.

The most common cause of acute oligohydramnios is an infectious disease. This form of pathology leaves fewer negative consequences for the baby’s health and does not require special treatment, since the situation usually stabilizes with the successful elimination of the disease that caused it.

In addition, oligohydramnios is classified depending on the functional activity of the cells of the aqueous membrane. Based on this principle, primary and secondary forms are distinguished. Primary oligohydramnios is characterized by the absence of any functional disorders in the membranes. With secondary oligohydramnios, damage to the structure of the amnion is observed, causing water to leak out.

Symptoms

Quite often, the clinical picture of moderate oligohydramnios does not have pronounced manifestations (therefore, this condition in some cases can be regarded as borderline with the norm). However, a pregnant woman should pay attention to some signs characteristic of this condition, if they occur. Among these symptoms:

lower abdominal pain;
painful tremors;
weak and infrequent tremors;
the size of the uterus does not correspond to the duration of pregnancy (detected by an obstetrician-gynecologist).

If any of these symptoms appear, even if they seem minor, you should immediately report them to your doctor so that he can prescribe a series of examinations that can help identify oligohydramnios.

Possible complications

Insufficient volume of amniotic fluid can become an impetus for the development of a number of complications, among which:

Impaired blood flow in the umbilical cord. Because of this, the baby does not get enough oxygen and food. Persistent hypoxia can provoke the development of irreversible disorders in a child and even lead to his death.
“Failure” in the process of circulation of amniotic fluid. This condition can lead to infection, and also greatly increases the likelihood of a traumatic birth.
Flat amnion. This complication can provoke a weakening of labor in the first stage of labor.
Placental abruption. Small fragments of the placenta are retained in the uterus, which increases the risk of bleeding.
Fetal underdevelopment. If during the process of intrauterine development a child regularly did not receive the amount of nutrients and microelements he needed, then his body weight at birth will be less than normal.

Diagnostic methods

The main instrumental diagnostic methods used by the doctor to determine the volume of amniotic fluid are ultrasound and Doppler sonography. With their help, you can evaluate umbilical blood flow, how much the child is lagging behind in development, as well as the condition of the blood vessels of the expectant mother and fetus.

In addition, an obstetrician-gynecologist may additionally prescribe cardiotocography to study the functional capacity of the baby’s cardiovascular system. With established moderate oligohydramnios in the third trimester This study is carried out at 30, 34 and 36 weeks of pregnancy.

When registering, a woman must undergo screening for sexually transmitted infections.

Therapy

Correction of this condition should be carried out in several directions:

prescribing medications that normalize metabolic processes in the placenta;
drug therapy for the underlying disease.

If a pregnant woman suffers from any disease associated with metabolic disorders or is overweight, then most likely the specialist monitoring the pregnancy will recommend adhering to a special diet.

Moderate oligohydramnios usually does not require constant monitoring in a hospital setting, the future condition can be normalized on an outpatient basis.

In addition to drug therapy, with moderate oligohydramnios, the expectant mother must observe some restrictions regarding her physical activity. She should also make sure that her daily diet includes foods rich in vitamins and microelements.

The duration of pregnancy plays a largely determining role in drawing up a treatment plan. This pathology requires the most careful monitoring in the 2nd trimester. If oligohydramnios is diagnosed at 37 weeks, this may be an indication for a cesarean section.

Prevention

Currently, no effective methods have been developed to prevent the risk of developing oligohydramnios. But there are a number of recommendations, the exact implementation of which will help a pregnant woman reduce the risk of this pathology.

Plays an important role diet of the expectant mother. It must be rich in all the elements (vitamins, proteins, microelements and other valuable substances) necessary for the normal development of the fetus and ensuring the satisfactory condition of the pregnant woman.

It is very useful for the expectant mother and the health of her baby to follow a balanced regime of physiological stress and rest. Work should be moderate, since excessive overwork can have a detrimental effect on the health of the woman and her baby.

However, you should not go to extremes and completely deprive yourself of even minimal exercise, as this can lead to rapid weight gain, which can complicate the course of pregnancy.

One of the main factors determining the nature of pregnancy and the success of delivery is emotional background of a woman. The presence of stress and regular mental overload sharply increases the risk of developing any associated complications, including oligohydramnios. A pregnant woman needs to undergo all examinations prescribed by a doctor on time.

It is necessary to use any supplements or medications only with the approval of a specialist, and not based on incompetent reviews.

Conclusion

Moderate oligohydramnios occurs against the background of certain pathologies of intrauterine development of a child or diseases of a pregnant woman. Its distinguishing feature is the absence of pronounced symptoms. At timely therapy this deviation does not pose a great threat to the normal development of the fetus and the health of the expectant mother. The period at which moderate oligohydramnios was diagnosed is important, since at different periods of pregnancy such a disorder can have its consequences.

Under certain negative circumstances, pregnancy can be accompanied by a number of different kinds of problems and complications, among which oligohydramnios is reasonably considered one of the most dangerous. This pathological condition is characterized by a decrease in the volume of amniotic fluid, without which the developing fetus may simply die.

Amniotic fluid is a nutrient medium from which the developing fetus receives the substances it needs during its stay in the mother's womb. The composition of amniotic fluid includes many nutritional components, without which normal growth and development of the child is impossible. The main components of the environment are: oxygen, vitamins and microelements, salts, some hormones, as well as many additional useful substances.

In addition to providing the child with the necessary nutritional components, amniotic fluid protects the fetus from various types of infections and, in general, all kinds of negative influences. The amount of intrauterine fluid changes as the child grows and his needs increase.

Based on average statistical data obtained from numerous clinical studies, amniotic fluid indices were determined for each period of pregnancy. This index reflects the norm of amniotic fluid volume and permissible deviations that are not a cause for concern.

We talk about oligohydramnios in cases when the patient’s amniotic fluid index is not within the lower limit of the norm for her period. Information regarding the normal volume of intrauterine fluid for different weeks of pregnancy is given in the following table.

Table. Amniotic fluid index for different weeks of pregnancy (16-25)

Gestation period, weeks	Average normal value, mm	Probable fluctuations, mm
16	121	73-201
17	127	77-211
18	133	80-220
19	137	83-225
20	141	86-230
21	143	88-233
22	145	89-235
23	146	90-237
24	147	90-238
25	147	89-240

The determination of the mentioned indicators is carried out by a doctor during the next ultrasound examination.

The list of factors contributing to the development of oligohydramnios remains virtually unchanged for each stage of pregnancy. Among the most common reasons, the following points should be noted:

kidney pathologies in the fetus. In the presence of severe congenital diseases of this nature, oligohydramnios is usually observed from the initial stages of pregnancy;
illnesses of a chronic nature, usually affecting the genitourinary and cardiovascular systems of the mother;
infectious diseases affecting the mother’s genitourinary system;
bad habits in women;
previously suffered bacterial and viral diseases;
pathologies of the placenta;
multiple births (often a combination of oligohydramnios in one child and simultaneous polyhydramnios in the second).

How does oligohydramnios manifest itself?

The problem under consideration can be severe or moderate. Moderate oligohydramnios is characterized by an almost complete absence of subjective manifestations felt directly by the patient - the pregnant woman’s well-being practically does not deviate from the norm, and the lack of intrauterine fluid is determined only during an ultrasound examination.

For the expressed form of the disease in question, the following manifestations are characteristic:

reduction of the uterus. During the next medical examination, the specialist notes a decrease in the patient’s abdominal circumference. During a vaginal examination, it is discovered that the height of the uterine fundus does not correspond to the normal readings characteristic of the patient’s specific period of pregnancy;
pain when the child moves;
periodic discomfort of aching nature in the abdomen;
deterioration of the woman’s condition in general, accompanied by a feeling of dry mouth, as well as nausea and severe weakness.

Oligohydramnios, diagnosed in the second trimester (namely, this period of pregnancy includes the 20th week), is the most dangerous for both the developing fetus and the woman carrying it. The specialist’s task at this stage is to determine the feasibility of prolonging the pregnancy.

It was previously noted that oligohydramnios comes in two main varieties. The most dangerous, in this case, is the pronounced form of the disease, which can lead to the following problems:

disorders and pathologies of child development. Children born with oligohydramnios often experience deformities of the limbs and muscles, spinal abnormalities, a general slowdown in development, and pathologies in the formation of the brain and skull. The most severe complication of oligohydramnios is hypoxia, which develops against the background of oxygen starvation. The possibility of the child’s death cannot be ruled out;
problems during childbirth. Even if the pregnancy can be maintained, labor activity in the future will most likely be extremely weak. There is a high risk of severe blood loss after delivery;
termination of pregnancy.

In patients with moderate oligohydramnios, the likelihood and intensity of manifestation of the listed deviations is lower, however, the risks of the occurrence of the described problems are also present.

That is why the main task of a woman who has had to deal with oligohydramnios at the 20th week of pregnancy or any other period is to strictly follow medical recommendations.

Treatment of the problem under consideration is an extremely difficult and responsible task that requires a qualified approach. Currently, medicine does not have drugs or special techniques that can artificially increase or decrease the content of amniotic fluid.

If oligohydramnios is detected, the woman is hospitalized in a hospital and all necessary medical measures, the main task of which is to maintain the normal condition of the child and balance the uteroplacental circulation, are carried out under close medical supervision.

The course of treatment is determined by a specialist. As a rule, women are prescribed vitamins, medications to normalize placental function and improve uteroplacental blood flow, and antibiotics (if various types of infectious diseases have caused oligohydramnios).

During therapy, doctors constantly monitor the amount of amniotic fluid and monitor the condition of the developing child. Procedures such as fetal cardiotography, ultrasound, and Doppler measurements are regularly performed.

If the measures taken do not have a positive effect on the condition of the patient and the child, and oligohydramnios progresses, doctors in the vast majority of cases recommend early delivery, which at the 20th week of pregnancy is often equivalent to abortion.

In general, as practice shows, with timely diagnosis and proper treatment, the problem of oligohydramnios can be quite successfully solved. Many experts regard this disease as a symptom of another disease, so the main goal of prescribed therapy in most situations is to identify and eliminate the causes that led to the development of amniotic fluid deficiency.

In addition to medications, women are recommended to reconsider some aspects of their life activities. For example, experts often advise reducing physical activity.

Thus, although oligohydramnios is a rather dangerous disease, often threatening the death of the fetus, with a timely and competent approach, there is a high probability of normalization of the condition of the child and mother and the chances of having a healthy baby are significantly increased. The main thing is to strictly adhere to the recommendations of specialists, not to self-medicate and to approach the solution of the problem as responsibly as possible.

Be healthy!

Video - Oligohydramnios during pregnancy 20 weeks

According to statistics, about 4% of all pregnant women are diagnosed with “oligohydramnios” on ultrasound. The expectant mother begins to worry about how the lack of amniotic fluid will affect the child. And this is a completely normal reaction. After all, oligohydramnios during pregnancy can be a consequence of serious disorders in both the child and the mother. What to do in such a situation? For what reasons does this condition occur and what consequences does it have?

Purpose of amniotic fluid

Water, or amniotic fluid, surrounds the baby throughout the pregnancy. They are located in the amniotic sac - a kind of “sac” in which the fetus forms and develops. By the end of pregnancy, the amount of water is 800-1500 ml. They are constantly updated - approximately once every 3 days.

With each subsequent month, the amount of amniotic fluid increases. At first, the baby moves easily. However, in the last trimester, despite the increase in the amount of amniotic fluid, he becomes cramped.

Amniotic fluid plays an important role:

They help create the habitat necessary for the fetus.
Contains nutrients and vitamins.
Prevents fusion of the baby's skin and the amniotic sac.
Protects from injury.
Allows you to move. Movement is very important for fetal development.
Protect the umbilical cord and placenta from damage as a result of the baby's movements.
If there is a sufficient amount of amniotic fluid in the amniotic fluid, the baby will take the desired position at the time of birth.
Thanks to the waters, it is easier for the mother to tolerate the motor activity of the fetus.
The waters help open the cervix during childbirth.

Why is there not enough water?

Oligohydramnios is a decrease in the amount of amniotic fluid. Typically, this diagnosis is made in the last weeks of pregnancy if the amount of water decreases to 500 ml. In the classic version, oligohydramnios is a deviation from the norm just before childbirth. However, this phenomenon occurs at 20, 30, 33 and even 35 weeks. For what reasons does this condition develop?

Factors that cause oligohydramnios during pregnancy are divided into 5 groups.

Congenital malformations of the fetus

Improper formation and development of urethral valves.
Complete absence of the urethra or its narrowing.
Too narrow ureters.
Complete absence of the muscles of the anterior abdominal wall and malfunctions of the urinary system.
Lack of kidneys.
Polycystic disease (formation of cysts in both kidneys).

Fetal pathologies

Infection of the fetus with cytomegalovirus, chlamydia, etc.
Slow development.
Down syndrome and other chromosomal disorders.

Chronic diseases of the mother

Diseases of the heart and blood vessels, such as hypertension or venous insufficiency.
Preeclampsia (toxicosis of the second and third trimester).
Pyelonephritis, renal failure and other kidney diseases.
Lupus, arthritis, rheumatism and other diseases from the collagen group.
Overweight.
Diabetes.
Dehydration.
Smoking.

Problems with the placenta

Failure.
Placental infarctions.
Abnormal development, for example, amnion necrosis or atrophy.

Other factors

More than 42 weeks of pregnancy.
Injuries to the amniotic sac.
Water leakage.
Death of the fetus inside the womb.
Long-term use of drugs that allow you to maintain pregnancy and delay childbirth.

It turns out that most causes of oligohydramnios can be prevented. It is impossible to correct only congenital malformations.

However, they can be detected by ultrasound, which is performed at 12, 20 and 35-36 weeks.

Now the most common causes of oligohydramnios in pregnant women are considered to be gestosis, hypertension, diabetes mellitus, colds or ARVI, TORCH infections (toxoplasmosis, rubella, etc.), chronic oxygen starvation of the fetus.

TORCH infections, in addition to oligohydramnios, cause developmental defects in the child. To avoid problems, you need to get tested for these infections before conception.

If oligohydramnios is caused by an acute respiratory viral infection or a common cold, there is no reason to worry. The amount of water will be restored within a month.

Classification

The duration of oligohydramnios during pregnancy can be acute or chronic:

Acute occurs spontaneously and is called benign. Such oligohydramnios is usually associated with external circumstances, such as colds.
In the second case, oligohydramnios develops latently, and its causes are difficult to eliminate. A woman must undergo a thorough examination to prescribe therapy. Chronic oligohydramnios will not go away on its own; it can progress.

According to the time of development, oligohydramnios can be early or late:

Early oligohydramnios is considered the most dangerous. It usually appears between 16 and 20 weeks. During this period, the child develops most actively. Therefore, it is worth undergoing a detailed examination and starting treatment immediately.
Late oligohydramnios appears mainly in the third trimester. May be a consequence of abnormalities in fetal development.

Based on injuries to the membranes, oligohydramnios can be primary or secondary:

Primary may appear in intact membranes.
Secondary appears when the membranes are damaged and water leaks.

How does it manifest?

It is very difficult to notice oligohydramnios on your own at any stage, be it 20, 33 or 35 weeks of pregnancy. For a woman to suspect something, there must be critically little water. With moderate oligohydramnios, the expectant mother does not experience any symptoms.

If oligohydramnios is severe, the baby becomes cramped in the uterus, and his every movement is reflected in pain in the pregnant woman’s body.

A gynecologist may suspect oligohydramnios if the size of the uterus does not correspond to the gestational age or parts of the baby’s body are easily palpable. At the slightest suspicion, a pregnant woman will be sent for an ultrasound, where a specialist will determine the amniotic fluid index (measured in millimeters).

What is the danger?

Does oligohydramnios always have a negative effect on the child and mother? What could be the consequences of this condition? It is difficult to give an unambiguous answer to these questions - it all depends on the timing and reasons.

If a lack of amniotic fluid occurs in the middle of pregnancy, between 17 and 27 weeks, the baby is squeezed from all sides by the walls of the uterus. There is no room left for him to move and grow.

As a result, some deviations in its development may appear:

clubfoot,
dislocated hips,
deformation of the skull.

If you consult a doctor in time, these defects can be eliminated.

What could be the consequences if oligohydramnios occurs in the later stages, from 35 weeks to the time of birth? Childbirth will involve some difficulties. With oligohydramnios, the amniotic sac becomes flat and does not in any way contribute to the opening of the cervix. As a result, the birth process is delayed. In most cases, doctors decide to perform a caesarean section.

Women who suffer from oligohydramnios have a much higher risk of bleeding in the postpartum period.

The most dangerous period

The critical period is considered to be 30-33 weeks. Oligohydramnios occurs more often at 30-33 weeks than at other periods and is a consequence of oxygen starvation of the fetus. In this condition, all the blood collects in the brain and heart. The lungs and kidneys are starving. The process of producing amniotic fluid, for which these organs are responsible, is disrupted.

At 30-33 weeks, the amniotic fluid index ranges from 74 to 274 mm.

Doctors call this period critical: oligohydramnios can lead to serious consequences and even provoke the death of a child.

How is it treated

Management of pregnancy and childbirth, as well as possible therapy, depend on the trimester in which oligohydramnios occurred and how severe it is. The most risky is the second trimester. In case of danger, doctors try to prolong the pregnancy for as long as possible so that the baby has time to develop and become viable. This process is called prolongation.

If oligohydramnios is detected in the third trimester, it will be difficult to prolong the pregnancy. In the absence of disturbances in the development of the child, delivery is indicated at a period of 37-38 weeks.

To alleviate the condition of a pregnant woman, doctors eliminate the cause of oligohydramnios. They also prescribe medications to improve blood flow in the placenta. It is important to constantly monitor the baby’s condition using ultrasound, CTG (cardiotocography) and Doppler.

If the fetal condition worsens sharply according to CTG data, a cesarean section is performed.

Reverse situation

Sometimes a woman develops a condition that is completely opposite to oligohydramnios - moderate polyhydramnios during pregnancy. This is an increased level of amniotic fluid.

As with oligohydramnios, the causes of polyhydramnios are chronic diseases and problems in fetal development. This condition can also be a consequence of pregnancy with twins, triplets, etc.

Even moderate polyhydramnios during pregnancy can seriously complicate childbirth and postpartum recovery. In addition, it is very dangerous for the child.

So, oligohydramnios and polyhydramnios during pregnancy occur due to diseases of the mother’s body or disorders in the development of the fetus. It doesn’t matter what stage of pregnancy you are: 20, 33, 35 or 40 weeks, in order to avoid serious consequences, you need to follow all doctor’s orders.

Sometimes, in order to preserve the pregnancy, a woman may be sent to the maternity hospital (or rather, to the pathology department) ahead of her due date. We will look at one of the reasons that may lead an expectant mother to an inpatient hospital for treatment.

After the next ultrasound, a woman may hear a diagnosis of “oligohydramnios”. After this, the pregnant woman rushes to her doctor to find out why oligohydramnios is dangerous during pregnancy, how a small amount of fluid can affect childbirth, the condition of the fetus, and what treatment is effective.

The value of amniotic fluid

Throughout pregnancy, the fetus is limited to the space of the uterus. In addition to the baby itself, the placenta and fetal membranes are necessarily present in the womb. These components are necessary only during pregnancy and are formed after conception, therefore, after the birth of the child, they are rejected from the mother’s body in the form of an afterbirth.

The water membrane (or amniotic sac) is a kind of “bag” in which the fetus develops, washed on all sides by amniotic fluid. In most cases, the amount of liquid by the end of the period is approximately 800-1500 ml. The waters are constantly renewed, the full renewal cycle is about 3 days.

The amount of fluid constantly increases as pregnancy progresses. In the first and second trimester, the child can still move relatively freely in the uterus, but by the third trimester the amount of water increases, and with it the child himself becomes larger, which leads to severe “crowding.”

The value of amniotic fluid for a child is invaluable:

They create a necessary and structurally unique habitat for the fetus.
Prevents the baby's skin from fusing with the amniotic sac.
Protect the baby from injury.
They help the child move actively, which is very necessary for the proper development of the fetus.
Protect the placenta and umbilical cord vessels from the baby’s movements.
The required amount of water allows the baby to take the correct position by the end of pregnancy.
They smooth out and make the baby’s movements less noticeable for the mother.
Together with the amniotic sac, they contribute to the dilatation of the cervix during childbirth.

Low level of AFI - oligohydramnios

In obstetrics, the case when the level of amniotic fluid does not reach normal levels is called oligohydramnios. The causes of this condition are varied, here are the most common:

Amnionic hydrorhea. When amniotic fluid begins to leak much earlier than the PDR (). This complication occurs due to rupture of the membranes. The causes of this condition have not yet been studied; experts believe that rupture may occur due to the thinness of the membranes, which occurs as a result of viral infection or their aging. A very small amount of water flows out through the gap that appears as a result of the rupture, but this happens constantly. In this case, the woman needs bed rest - in this case, the amniotic fluid has time to renew itself and the child is not in danger.
Anomalies in the development of membranes - there are quite a few of them. The cause of any of these disorders may be poor ecology, genetic factors, and others.
Infection of the membranes. This situation occurs most often. Infection of the fetal bladder with viruses (this can be measles, ARVI, chicken pox, influenza, and many others) occurs because the placental barrier is not able to protect the fetus from this type of infection. Sometimes infection occurs due to STDs (sexually transmitted diseases). Toxins that are produced as a result of the activity of viruses poison the fetal membranes and disrupt its functioning.
True post-term pregnancy. In this case, the fetal membranes and placenta no longer perform their full functions, and this leads to the fact that the child begins to lack nutrients and his general condition worsens. Blood circulation in the amniotic membranes worsens, resulting in a decrease in the production of amniotic fluid.

What is the danger?

This condition while expecting a child is fraught with various complications. If there is very little amniotic fluid, then the walls of the uterus begin to tightly adjoin the fetal sac, which leads to strong pressure on the child - he bends in an uncomfortable position. This can lead to the following consequences: curvature of the spine, clubfoot, accretion of the skin to the fetal membrane. The skin of the fetus becomes wrinkled and dry.

With prolonged and severe oligohydramnios, close contact of the amniotic sac with the baby’s skin can lead to the formation of Simonart’s ligaments. They wrap around the fetus, interfere with its activity, and in some cases can even lead to serious injury. When they wrap around the umbilical cord, this leads to disruption of blood flow in the vessels, as a result, the child may experience delayed physical development, and in especially dangerous cases, fetal death.

Severe polyhydramnios is physically felt even by a pregnant woman. This is constant pain in the lower abdomen in the second and third trimester. When the child moves, the mother experiences pain. This is especially felt at 36-42 weeks of pregnancy, when the fetus is already quite large.

If there is very little amniotic fluid, labor is often accompanied by slow dilatation of the cervix and weakness of labor develops. The contractions are painful, but their effectiveness is very small. Bleeding may occur after childbirth.

Treatment. Should moderate oligohydramnios be treated?

Quite often, a moderate (slight) reduction in the amount of water (400-700 ml) is the norm. In this case, a pregnant woman is recommended to reduce physical activity, eat nutritiously, take multivitamin complexes and be sure to see a gynecologist at the antenatal clinic. To exclude further reduction of water, additional unscheduled ultrasound may be required. If the symptoms of oligohydramnios become more and more pronounced, and the amount of fluid becomes less than 400 ml, mandatory treatment in the department of pathology of pregnant women is necessary.

As soon as the doctor determines that a woman has oligohydramnios, she is sent to the maternity hospital for additional tests. Additional studies are carried out in the hospital:

CTG (cardiotocography);
laboratory tests (blood and urine tests).

If the gynecologist suspects that a woman has amnionic hydrorrhea (amniotic fluid is leaking), then she needs to do a smear test.

When a woman is 38 weeks pregnant or more, the cervix is already preparing for childbirth and its canal can be missed by the amnioscope. In this case, the doctor can more accurately determine the amount and composition of amniotic fluid using amnioscopy. This procedure does not violate the integrity of the membranes and is not dangerous for the child.

The tactics that the doctor chooses for treatment largely depend on the cause that caused this complication.

If the cause is amnionic hydrorrhea, then the pregnant woman needs strict bed rest, vitamin complexes, and medications that help reduce the tone of the uterus and prevent infection of the child and membranes. Most likely, the woman will remain in hospital treatment until delivery in order to constantly monitor the condition of the fetus.
Is oligohydramnios caused by a viral infection? Then restorative and antiviral drugs are needed. In addition to them, vitamin therapy and drugs that improve blood microcirculation are needed. If the doctor sees positive dynamics, he may send the expectant mother home with mandatory monitoring of her condition in the housing complex.
Does the expectant mother have an abnormal development of the membranes? In this case, therapy aimed at maintaining pregnancy and preventing intrauterine infection is necessary. Treatment is carried out in the department of pathology of pregnant women. Constant diagnostics of the condition of the fetus and the woman herself is carried out.
If there is postmaturity, the bladder will be punctured - amniotomy. After this, labor begins.

If oligohydramnios is detected in time and treatment is started, the prognosis for this pregnancy is in most cases favorable.