What does amniotic index mean. Water essential for life: amniotic fluid

Amniotic fluid is involved in the metabolism of the child and protects him from injury, and their study helps to identify deviations from the norm.

40 days after fertilization, a fetal bladder is formed around the embryo, consisting of two membranes - chorion (external) and amnion (internal). The amnion produces fluid that accumulates and renews itself, which is why it is called amniotic. Partially, amniotic fluid is produced by the body of the mother and fetus, depending on the duration of pregnancy, they contain albumin (the main protein in blood plasma), fats, organic and inorganic salts, hormones, enzymes and vitamins, epithelial cells.

Water, like the fetal bladder, protects against mechanical damage, infections, temperature fluctuations and other adverse irritants, in addition, they are involved in the metabolism between mother and child. Thanks to the amniotic fluid, the work of the urinary tract and lungs of the baby is getting better. Update occurs every three hours with the help of amnion cells, part is absorbed by the mother's body through the umbilical cord, so the fidget always swims in a clean "pool".

Amniotic fluid rates by week

The amount changes with the duration of pregnancy - by the end of the first trimester, about 100 ml, in the third trimester up to 1.5 liters, problems such as polyhydramnios or oligohydramnios are equally dangerous for the fetus. The disadvantage speaks of problems with the kidneys of the mother or baby; on the part of the woman, this problem is often provoked by preeclampsia or diseases of the blood vessels. Children with oligohydramnios are born with low body weight, are at risk of hypoxia during childbirth, and there may be a problem with breathing after birth.

Excess indicates poor functioning of the gastrointestinal tract and kidneys in the fetus. In case of a serious violation of the norm, appropriate treatment is carried out (, amnioreduction,).

Amniotic fluid index - weekly norm

The volume, composition and type of amniotic fluid is of great diagnostic importance. The volume is measured using ultrasound at 20-22 weeks of gestation, the sum of the measurements is indicated in centimeters as "AFI". The correct value is in the range 5-20, a value less than 5 indicates oligohydramnios, more than 20 indicates polyhydramnios. An accurate diagnosis is made only by a doctor, slight fluctuations from the average are possible. A visual assessment of the waters is carried out with the help of an amnioscope inserted into the cervical canal of a woman, which allows to assess the color and volume.

Amniocentesis is performed in extreme situations. Through a puncture of the abdominal wall and uterus, a sample of amniotic fluid (15-20 ml) is taken with a thin needle, after which it is subjected to various tests. The study shows the absence or presence of fetal infections, genetic diseases of the fetus, the degree of lung maturity is assessed.

Dangerous symptoms

The norm of amniotic fluid for weeks is disturbed by leakage, this symptom requires special attention and an immediate visit to the doctor's office. How to distinguish water from vaginal discharge or urine? Amniotic fluid has a weak specific smell or none at all, at the beginning of pregnancy they are transparent, and closer to childbirth they are cloudy. A change in color to brown, greenish or yellow indicates an emergency when urgent hospitalization is required.

Green indicates severe hypoxia, brown indicates the death of the baby. Yellowish color is the norm for the last trimester. Pinkish water after 38 weeks of pregnancy is a harbinger of childbirth, before 38 weeks - placental abruption or other problems that cause internal bleeding in the mother or baby.

Leakage leads to infection of the fetus, urgent medical attention is needed!

The official medical name for amniotic fluid is amniotic fluid. It is a liquid biologically active medium that is located in the fetal membranes and covers the embryo.

Functions of amniotic fluid

Amniotic fluid is one of the factors in ensuring the life of the child in the womb. This biological environment is characterized by several functions at once:

• Feeding the fetus. This liquid is made up of many nutrients. In the first period after fertilization, they are absorbed through the skin of the child, and a little later, the baby independently swallows a certain amount of them.
• Maintaining the appropriate pressure and temperature regime within 37 ° C.
• Providing a developing child with protection from external mechanical influences. significantly reduce the pressure and shocks that come from the external environment.
• Support of sterility, which is to protect the child from a variety of infections. The amniotic fluid contains a lot of immunoglobulins. In addition, the absolute tightness of the fetal bladder plays an important role. Sterility is ensured by the constant renewal of amniotic fluid, which ends only after the birth of the child.
• Ensuring the free movement of the baby in the uterus.
• Muting strong external noise.

The main indicators of amniotic fluid

Throughout the entire period of pregnancy, the composition and number of amniotic fluid are very important. There are many cases when abnormal indicators indicate the formation and development of various pathologies. Thus, it is possible to diagnose and eliminate them in time, or to properly prepare for the necessary measures after the birth of the baby.

The amniotic fluid index (AFI) is a number that indicates its volume in the amniotic sac.

When conducting a diagnosis, a specialist takes into account the following indicators:

• Hue and transparency. The usual color of the liquid is light, transparent, with a small amount of impurities.
• Volume. The amount of fluid is affected. Therefore, the rate of amniotic fluid depends on the trimester of pregnancy. For example, the amniotic fluid index at 21 weeks (normal) is 88-143-233 ml, where the first indicator is the lower norm, and the second number is the average, the third is the upper limit. The daily increase in the amount of fluid by 40-45 ml continues until After the amniotic fluid index at 32 weeks (the average norm is 144 ml) has reached its peak, the amount of water gradually decreases. On the eve of childbirth, it is only 500-1500 ml.
• hormonal content.
• Biochemical and cytological compositions.

Amniotic fluid indicators

The most informative criterion for oligohydramnios in our time is ultrasound. When conducting this study, the doctor determines the AFI and the multiplicity of the vertical pocket. If these indicators do not reach the normal limits for a given gestational age, then oligohydramnios is indicated in the conclusion.

Vertical pocket is the name of the longest section of free amniotic fluid that is located between the fetus and the anterior abdominal wall. In addition, the location of the free fluid of the umbilical cord or the limbs of the child is not allowed in this area. The norm of the length of the vertical pocket is 5-8 cm, a little earlier, using ultrasound, only this indicator was established.

Amniotic fluid index norms

Now the amount of amniotic fluid is assessed using IAF. To do this, the doctor mentally divides the abdomen into 4 parts using 2 perpendicular lines intersecting at the navel. After that, in each of these zones, the measurement of the maximum vertical pocket is carried out. In order to get the final value of the amniotic fluid index, it is necessary to add up all the obtained indicators.

The norms of the amniotic fluid index are calculated by weeks of pregnancy, starting from the 16th week. Their value is gradually increasing. The highest at 32 weeks is the norm from 77 to 169 ml. This is followed by a decrease in IAI.

IAI norm table

The norms of the amniotic fluid index by week are presented in the table.

If these indicators do not correspond to specific lines of pregnancy, polyhydramnios or oligohydramnios occur.

oligohydramnios during pregnancy

Oligohydramnios is a rather unpleasant and very common phenomenon during pregnancy. If the deviation of the amount of amniotic fluid from the norm of the amniotic fluid index for weeks is insignificant, a diagnosis of "moderate oligohydramnios" is made. In order to correct it, you can use a diet, proper nutrition and a healthy lifestyle. After a while, the amount of water returns to normal and in no way affects the child's condition.

The diagnosis of "pronounced oligohydramnios" is made in the case when the deviation from the norm of the amniotic fluid index by weeks down is large. With such a diagnosis, urgent hospitalization and inpatient treatment are necessary. This is due to the high likelihood of dire consequences for the child.

If the amniotic fluid index at 20 weeks (normal) is in the range of 86-230 ml, and the ultrasound results indicate a much lower real volume of amniotic fluid, if left untreated, this can provoke the underdevelopment of vital organs, skeletal bone deformity, and the development of various fetal pathologies. Therefore, it is very important to start the treatment of severe oligohydramnios in time.

When a low index of amniotic fluid was determined at 34 weeks (the norm is an average of 142 ml), in addition, there are already well-defined deviations in the development of the child - the question often arises of terminating a pregnancy, since treatment in this case is meaningless and will not bring any results.

Reasons for the development of oligohydramnios

There are many reasons for the formation of oligohydramnios. The main ones are:

• underdevelopment of fetal membranes or reduced secretion of water;
• abnormal development of the fetus (its kidneys, skeleton);
• high blood pressure in the expectant mother, especially with significant deviations from the norm;
• bacterial infections that penetrate not only through the genital tract, but also directly into the amniotic fluid;

• multiple pregnancy, with uneven development of the placenta, giving a different blood flow to each fetus;
• overwearing;
• impaired metabolism in the body of a woman, especially in the presence of excess weight.

Features of the treatment of oligohydramnios

Even moderate oligohydramnios cannot be treated on its own. Only on the basis of previously made analyzes, the doctor can assess the cause of the anomaly, the severity of the disease, the condition of the fetus and prescribe a course of treatment.

If there is obesity, impaired metabolism, it will be necessary to follow a diet, eat right, take vitamins and drugs that improve the blood supply to the placenta. Therapy can be done on an outpatient basis. A pronounced stage is treated only in a hospital. Regardless of the form of the disease, there is a need to limit motor activity and the amount of physical activity, adherence to bed rest.

During treatment, it will be necessary to do ultrasound and dopplerography more often than usual to timely determine changes in the bodies of the pregnant woman and the baby.

If the ultrasound results showed a low amniotic fluid index at 33 weeks (the norm is an average of 143 ml) or later, when the baby is ready to be born, the doctor may prescribe an early delivery.

When you discover this fact, do not get depressed. Still can be corrected - moderate stages are treatable. In the presence of oligohydramnios during previous pregnancies, it is necessary to inform the doctor about this. In this case, he will be able to detect and fix this problem in a timely manner.

Amniotic fluid, which in medicine is called amniotic fluid, is a liquid biologically active medium located inside the membranes and surrounding the fetus.

amniotic fluid functions

Amniotic fluid plays a significant role in ensuring the life of the child in the womb.

This biological environment performs several functions at once:

• Fetal nutrition. This liquid contains many nutrients. In the first weeks of pregnancy, they are absorbed through the skin of the baby, and in later weeks, the child himself swallows a small amount of them;
• Support for optimal temperature conditions - about 37 ° C, as well as pressure;
• Protection of the developing baby from mechanical influences from the outside. Amniotic fluid reduces pressure and the force of shocks coming from the external environment;
• Protection of the fetus from infections. The amniotic fluid contains a fairly large number of immunoglobulins. In addition, the fetal bladder is completely sealed;
• They provide the baby with free movement in the uterus;
• Protect your baby from loud noise. Amniotic fluid muffles the sounds of the external environment.

Amniotic fluid is similar in characteristics to blood plasma, but its composition is constantly changing and mostly depends on the gestational age. It includes: proteins, carbohydrates, fats; minerals and vitamins; enzymes and hormones; carbon dioxide and oxygen; immunoglobulins; the baby's vellus hair and particles of lubricant covering his body.

amniotic fluid readings

The composition and amount of amniotic fluid is important at all stages of pregnancy. In some cases, a deviation from the norm may indicate the presence of pathologies, which makes it possible to identify and eliminate them or prepare for appropriate activities after the birth of the baby.

For diagnostic purposes, the specialist takes into account the following indicators:

• Color and transparency. In the normal state, the liquid should be light, transparent, with a small amount of impurities (single in the field of view);
• Quantity. The volume of fluid depends on the gestational age, so the norm is determined in accordance with the trimester of pregnancy. For example, up to 32 weeks of pregnancy, the amount of water increases daily by 40-45 ml, but upon reaching this period, it begins to decrease. Before the birth itself, the amount of fluid can range from 500 to 1500 ml;
• The content of hormones;
• Biochemical and cytological composition.

weekly amniotic fluid index

Below is a table in which the first number indicates the gestational age, the second - the lower limit of the norm, the third - the average number, the fourth - the upper limit of the norm:

• Second trimester from 16 to 25 weeks, respectively: 73 - 121 - 201; 77 - 127 - 211; 80 - 133 - 220; 83 - 137 - 225; 86 - 141 - 230; 88 - 143 - 233; 89 - 145 - 235; 90 - 146 - 237; 90 - 147 - 238; 89 - 147 - 240;
• Third trimester from 26 to 42 weeks, respectively: 89 - 147 - 242; 85 - 156 - 245; 86 - 146 - 249; 84 - 145 - 254; 82 - 145 - 258; 79 - 144 - 263; 77 - 144 - 269;74 - 143 - 274;72 - 142 - 278;70 - 140 - 279;68 - 138 - 279;66 - 135 - 275;65 - 132 - 269;64 - 127 - 255;63 - 123 - 240; 63 - 116 - 216; 63 - 110 - 192.

When these indicators do not correspond to specific weeks of pregnancy, polyhydramnios and oligohydramnios occur.

Diagnostic method for evaluating amniotic fluid

An ultrasound examination allows the specialist to assess the transparency and amount of amniotic fluid. If the ultrasound results show a large number of suspensions and flakes, a pathology is suspected - oxygen deficiency in a child (hypoxia). In this case, immediate identification of the cause of the pathological condition and its elimination is required.

The amniotic fluid index, which changes week by week, is also determined by ultrasound. Doctors conditionally divide the uterine cavity into four parts, the largest free area between the fetus and the uterine wall (vertical pocket) is to be measured

Amnioscopy is a visual method for examining fetal fluids using a special device - an amnioscope. The indication for the procedure is the overbearing of the child and the chronic form of fetal hypoxia. You can not do it in case of placenta previa, with pelvic presentation of the fetus, as well as women with inflammatory diseases of the cervix and vagina.

The amnioscopy procedure does not require the administration of painkillers. It is carried out with a whole fetal bladder and a mature, smoothed cervix. The woman sits on the gynecological chair, and the doctor gently inserts the tube of the amnioscope into the cervical canal, and then directs the light. The size of the tube depends on the width of the cervical canal of the cervix. Amnoscopy allows you to examine the color of the amniotic fluid, see if there are impurities in them: flakes of the natural lubricant of the fetal body, blood, meconium.

Amniocentesis is a procedure that involves puncturing the amniotic membranes to obtain a sample of amniotic fluid. The obtained material is necessary for hormonal, biochemical and cytological analysis. Since the procedure is invasive, it is performed according to strict indications - with a serious suspicion of fetal chromosomal diseases. It is impossible to carry out such an event in the presence of acute and chronic inflammatory pathologies, regardless of their localization.

Amniocentesis is performed using an ultrasound machine. Under the control of the latter, a puncture (puncture) site is selected. As a rule, the puncture is done in the place of the greatest accumulation of amniotic fluid, free from umbilical cord loops. For research, take no more than 25 ml of liquid.

Why is the amniotic fluid index important?

In order for the pregnancy to proceed successfully, the child develops well, the amniotic fluid must have a certain composition and be present in a certain amount. Any deviations from the norm indicate the presence of pathology - polyhydramnios or oligohydramnios.

The diagnosis of polyhydramnios is made when the amount of fluid exceeds the norm. This pathological condition can occur in acute and chronic form. In the first case, the amount of liquid increases suddenly, in the second - gradually. Polyhydramnios is a rather dangerous condition, as it often leads to complications during pregnancy and during delivery. With a large amount of amniotic fluid, a woman in position should be in a hospital.

Violation of the formation and absorption of amniotic fluid threatens with oligohydramnios. Let's consider this concept in more detail.

What is low water?

An insufficient amount of amniotic fluid in obstetrics and gynecology is called oligohydramnios.

Amniotic fluid (or amniotic fluid)- the liquid environment in which the fetus is located during pregnancy.

This biological fluid performs several important functions. These include:

• protective function- the water shell protects the child from the penetration of infections (due to the tightness of the shells and the immunoglobulins that make up the water), from mechanical influences from the outside (for example, from shocks and shocks), loud sounds (water muffles them), external fluctuations in pressure and temperature (maintaining optimal pressure and a constant temperature of 37 ºС, of course, if the mother is healthy and her body temperature does not exceed 37.8 ºС);
• exchange function- the child absorbs the amniotic fluid, enriched with nutrients, and releases it back.
  To all this, the fetal waters provide free movement of the crumbs inside the womb. Therefore, with a normal amount of amniotic fluid, the baby is cozy and comfortable, he is protected and provided with everything necessary.

What is in the amniotic fluid?

With increasing gestational age, the composition of the amniotic fluid changes, and becomes more diverse and saturated, which makes the waters slightly cloudy in appearance. The amniotic fluid is secreted by cells of the aquatic membrane.

At the beginning of pregnancy, amniotic fluid is almost the same in composition as blood plasma. They contain nutrients (proteins and fats), vitamins and minerals, hormones, enzymes, and more.

From the second trimester, the composition of this biologically active fluid is supplemented by dead skin cells (as a result of the natural process of changing the old skin layer to a new one), the fluff (hairs) of the fetus, the original cheese-like lubricant of the fetal body and its waste products (sterile urine).

Fertile waters are updated every 3 hours.
Drinking water does not affect the amount of amniotic fluid. From excessive fluid intake in a pregnant woman, only edema will appear.

The norm of the amount of amniotic fluid

When the amount of amniotic fluid deviates from the norm, doctors diagnose oligohydramnios or polyhydramnios. The doctor-diagnostician determines the amount of fluid during an ultrasound scan, starting from the second trimester of pregnancy.

The volume of amniotic fluid in medicine is commonly referred to as the amniotic fluid index (AFI).

Table - The norm of the amniotic fluid index by week

The norms may differ slightly from those given above, depending on the type of ultrasound machine. And also the value can be written not in millimeters, but in centimeters (1 cm = 10 mm).

Also, the amount of fetal water characterizes another indicator - the vertical size of the largest (free) water pocket (VC). This size should normally be in the range from 2 to 8 cm (or from 20 to 80 mm), with a borderline amount of water - from 2 to 1 cm (from 20 to 10 mm), and with oligohydramnios - less than 1 cm (or 10 mm).

What are the causes of oligohydramnios?

Depending on the severity of the pathology, moderate and severe oligohydramnios are distinguished.

Often you can find in the ultrasound protocol the inscription - "tendency to moderate oligohydramnios." This means that it is possible that the expectant mother has health problems and needs more careful monitoring.

Moderate oligohydramnios- this is a slight deviation in the amount of fetal water from the norm. This type of deviation may be caused by the individual characteristics of the body of a pregnant woman or, in the worst case, may be a prerequisite for the occurrence of a more severe form of this pathology. In any case, doctors recommend prophylaxis of fetoplacental insufficiency (FPI).

Moderate oligohydramnios is not a critical situation, because the amount of water is a variable number, and can change several times a day. Perhaps there was an error in establishing the diagnosis and the doctor was to blame for this, who made a not very accurate calculation during the ultrasound, because the determination of the amniotic fluid index is a subjective and approximate matter. Therefore, you should not panic, in 8 out of 10 cases, pregnancy ends with a successful birth of a healthy baby.

Severe oligohydramnios poses a danger to the health of the fetus, so you must follow all the instructions of the doctor observing the pregnancy.

The causes of oligohydramnios, regardless of the degree of its severity:

• fetoplacental insufficiency;
• problems with the cardiovascular system in a pregnant woman (hypertension and others);
• diseases of the urinary system of the fetus (kidneys, for example);
• leakage of amniotic fluid (in violation of the integrity of the membranes);
• pathology in the development of fetal membranes;
• transferred bacterial infections during pregnancy or shortly before its onset;
• diabetes;
• late gestosis.

Most often, oligohydramnios occurs due to a metabolic disorder in a pregnant woman, as well as after viral diseases (ARI, SARS, and others) and with fetoplacental insufficiency.

Personal practice shows that ultrasound doctors often exaggerate the magnitude of the problem, and a slight deviation from the norm is already a disaster for them. Such pseudo-low water causes unnecessary stress for the expectant mother, but in fact, babies are born relatively healthy.

The only thing is that childbirth with oligohydramnios (even slight ones) can take place with some complications (poor opening of the cervix, painful contractions and prolonged labor due to breech or breech presentation of the fetus, which arose due to oligohydramnios). Although complicated childbirth can occur in any woman in labor, regardless of the amount of water.

obstetrician-gynecologist A. Berezhnaya

The occurrence of oligohydramnios during a post-term pregnancy is considered a common occurrence, since the placenta has grown old and can no longer fully perform its functions, therefore it exfoliates. Then doctors prescribe labor induction or conduct a planned caesarean section.

Why is oligohydramnios dangerous for the fetus?

Oligohydramnios (or oligohydramnios) is a complication of pregnancy, sometimes even dangerous for the fetus, because it is at risk of infection, as a result of which even its death can occur.

For example, with the loss of the integrity of the membranes - this is when there is leakage of amniotic fluid - the child becomes vulnerable to infections entering the membranes.

The genital tract of a woman is not sterile, pathogenic microorganisms constantly live in the vagina, “plus” immunity is weakened due to pregnancy. All this can lead to the multiplication of harmful bacteria that can penetrate the uterine cavity and infect the fetal membranes, causing their inflammation, called chorioamnionitis in gynecology. Without timely treatment, infection of the fetus itself occurs.

This is with regard to oligohydramnios, caused by a violation of the integrity of the membranes.

With severe oligohydramnios, regardless of the causes of its occurrence, the baby suffers from hypoxia (lack of oxygen), because of this, it lags behind in fetal development. In addition to all this, the baby is uncomfortable to be in such a “nest”, his neck is often twisted, and the bones of the face and head are susceptible to deformation due to squeezing them by the walls of the uterus.

Moderate oligohydramnios does not have such a critical effect on the health of the fetus: the baby is weak and lags behind in weight gain (so-called malnutrition is observed), his muscle tone is reduced (torticollis, clubfoot may develop), and mild fetal hypoxia occurs.

If the screening and urine / blood / smear tests are normal, the cardiotocogram (CTG) is in order and the fetus is developing well, and the pregnant woman has no complaints about her well-being, then the diagnosis of oligohydramnios is conditional. It’s just that obstetricians will prepare for labor induction, since there is a high probability of a post-term pregnancy, or for a caesarean section with a non-standard position of the fetus at the time of birth.

Diagnosis of oligohydramnios

With an ultrasound examination, the doctor makes some measurements and calculations to determine the amount of amniotic fluid, after which he makes a conclusion about oligohydramnios, a normal amount of water, or polyhydramnios.

A gynecologist can also suggest little or polyhydramnios at the next measurement of the circumference of the abdomen and the height of the fundus of the uterus, but a more accurate diagnosis can only be made with the help of ultrasound.

At home, you can only test for leakage of amniotic fluid. If watery discharge is often observed on the underwear, and the baby’s kicks began to be painfully perceived by the pregnant woman, although such discomfort was not felt before, or the size of the abdomen is small, although the gestational age has already exceeded 20 weeks, then it is advisable to conduct a special test. Perhaps the reason for everything is lack of water, caused by leakage of water due to a violation of the integrity of the membranes.

The test can be done at home by monitoring the discharge for some time, or by buying a special amniotic fluid leak test at the pharmacy and using it.

The “free” test is carried out as follows: empty your bladder, take a shower (without douching and possible water getting inside the vagina), dry yourself with a towel and lie down on a dry diaper. Lie still for 15 minutes, and then get up and see if a wet spot has appeared on the diaper. Ordinary secretions are not able to form and flow out so quickly, most likely, amniotic fluid is leaking. You can find out more precisely by contacting the LCD with a complaint about unusual discharge. There they will conduct a special test and say it is water or ordinary vaginal discharge.

The pharmacy test looks like a gasket, the surface of which will change color to blue or green if amniotic fluid leaks.

Staining also occurs with bacterial / viral discharge, so if spots of a blue-green hue are noticed on the surface of the pad, contact your gynecologist.

Any test for amniotic fluid leakage is recommended after 12 hours since the last intercourse, douching or use of vaginal suppositories.

Treatment of oligohydramnios

It is impossible to artificially increase the amount of amniotic fluid, so the treatment of oligohydramnios comes down to determining the causes of its occurrence. Further, the treatment of the root causes of oligohydramnios is carried out.

To determine the causes of oligohydramnios, a pregnant woman is referred for doppler ultrasound or cardiotocography (CTG), in order, first of all, to refute or confirm a violation of blood flow in the placenta.

If the fetoplacental circulation is still disturbed, then the patient is prescribed drugs to normalize it - Curantil, Actovegin.

Moreover, Curantyl is often prescribed as a preventive measure for placental insufficiency.

Often, the treatment complex includes medications that help normalize metabolic processes in the body of a pregnant woman (for example, Magne + B6) and support the normal functioning of important internal organs of a woman (for example, Hofitol).

It is also necessary to exclude the presence of infections in a pregnant woman. For this purpose, urogenital smears for STIs and from the throat + nose for cocci are re-taken, a blood test for TORCH infection is performed. If an infection is present, antibiotic therapy is prescribed.

Childbirth with oligohydramnios

With severe oligohydramnios, a planned caesarean section is prescribed. With a small volume of amniotic fluid, the fetal bladder takes on a flat appearance. Because of this, contractions will be irregular and weak, and labor can be long and difficult.

Moderate oligohydramnios is not a contraindication for natural childbirth. Even with a breech or breech presentation of the fetus caused by oligohydramnios, childbirth takes place safely for both the mother and her child.

Insufficient amount of amniotic fluid does not give the baby the opportunity to move freely inside the womb. Therefore, often the child takes a transverse or gluteal position and he can no longer roll over correctly.

There are various exercises that can help turn the baby into the right position, but their effectiveness has not been medically confirmed. Exercise can lead to cord entanglement, so you need to weigh the pros and cons before doing them.

The child in the mother's womb is in the amniotic fluid - this is the amniotic fluid that surrounds the embryo and is necessary for the normal existence of the baby during the intrauterine period. Amniotic fluid performs protective and metabolic functions. Water absorbs noise and absorbs shocks, protects the fetus from infections, and maintains a comfortable temperature.

The metabolic function is to nourish the embryo: it swallows the amniotic fluid along with the nutrients it contains and then excretes it back. With a sufficient amount of amniotic fluid, the embryo is reliably protected and provided with optimal conditions for development.

What is the IAI indicator, why is it needed?

Where does amniotic fluid come from and what does it consist of? In terms of composition and properties, intrauterine fluids at the beginning of the gestational period are similar to plasma: they contain vitamins, hormones and enzymes. In the second trimester, dead skin cells, embryonic lubrication, baby hairs and waste products appear in the waters. The amniotic fluid is renewed every few hours. In this case, the amount of water should correspond to a certain norm, depending on the duration of pregnancy. With a small amount of water, there is a risk of infection and even death of the fetus.

To determine the rate of amniotic fluid, the IAI indicator is used - the amniotic fluid index. It allows you to control whether the amount of amniotic fluid in a woman in labor is normal or whether the embryo suffers from oligohydramnios or polyhydramnios. How much intrauterine fluid a pregnant woman has is determined by ultrasound.

Methods for diagnosing the amniotic fluid index

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This article talks about typical ways to solve your questions, but each case is unique! If you want to know how to solve your particular problem - ask your question. It's fast and free!

subjective way

The amniotic fluid index is determined using ultrasound. That is why it is important to pass all the required ultrasound examinations on time: a planned ultrasound allows you to diagnose the lack of amniotic fluid in time and take the necessary measures to prevent fetal pathologies. The specialist will examine the uterus in different planes and visually determine the volume of fluid, visually assess the thickness of the water layer between the embryo and the abdominal wall and draw a conclusion about oligohydramnios or polyhydramnios. This diagnostic method is not accurate, so you should not rely on it.

objective way

Determining the volume of amniotic fluid by an objective method using ultrasound is carried out by dividing the uterine cavity into 4 equal segments. The abdomen is divided into squares, the marking axis is drawn through the middle vertically and through the navel horizontally. In each square, a space free from the fetus is selected, and the maximum distance from the child to the wall is measured. The four indicators obtained (the depth of the “pocket” in each square) are summarized and the total value of the amniotic fluid index is found.

IAI norms depending on the week of pregnancy

Amniotic fluid index norms change throughout pregnancy. At what time is the IAI maximum? For the first 27 weeks, the index gradually increases, and then by 30-32 weeks of gestation it begins to decrease. The average at 36 weeks is 13.8 cm. By week 40, the indicator reaches its minimum value.

The IAI norms for each woman are different and may be slightly less or more than the average, which is acceptable. The amount of amniotic fluid (in centimeters) at different times is shown in the table below.

Number of weeks	Average, cm	Possible fluctuation range, cm
16	12,2	7,20-20,2
18	13,4	8,1-22,1
20	14,2	8,7-23,1
22	14,5	9-24,1
24	14,8	9,1-24,3
27	15,6	9-24,5
30	14,5	8,3-25
32	14,5	8,0-26,8
33	14,4	7,4-27,5
34	14,3	7,3-27,4
35	14	6,9-27,2
36	13,8	6,8-27,1
40	12,1	6,4-24,5

Reasons for possible deviations

The volume of amniotic fluid may deviate in the direction of increase or decrease. Excessive accumulation of amniotic fluid (polyhydramnios) is not as common as oligohydramnios. An excess of fluid leads to breech presentation, contributes to premature birth, as well as fetal hypoxia and, accordingly, pathologies of its development. Causes of polyhydramnios: intrauterine infection, conflict between the Rh factors of a woman and a baby, diabetes mellitus, immune diseases, severe metabolic disorders in the mother's body.

Polyhydramnios during full-term pregnancy is considered a state when the volume of water exceeds 2000 ml. Polyhydramnios occurs in the second half of gestation and is clearly diagnosed at 34-35 weeks. In this case, the IAI indicator can exceed the average value by 2 times. The volume of water in some cases is more than four liters. It is necessary to carry out treatment aimed at regulating the placental-uterine circulation.

With a lack of amniotic fluid, oligohydramnios develops. Causes of a small amount of amniotic fluid in pregnant women:

• depressurization of the membrane of the fetal bladder and fluid leakage;
• defects of the fetal membrane;
• pathology of the kidneys in the baby and blockage of the ureters of the embryo;
• diseases of the kidneys or the cardiovascular system in a woman;
• late toxicosis (starting from 33 weeks);
• circulatory disorders in the placenta (fetoplacental insufficiency).

Oligohydramnios can be moderate and severe. A moderate degree implies a slight deviation in the volume of intrauterine fluid from acceptable values. This does not pose a great danger: the renewal of water occurs regularly, their number varies and depends on the individual characteristics of the woman. Severe oligohydramnios is observed, most often, at the end of pregnancy.

The amniotic fluid index can reach values ​​that are half the average. This degree of pathology poses a threat to the baby and can cause complications during childbirth.

Concomitant symptoms of pathological abnormalities in the volume of amniotic fluid

With polyhydramnios, a pregnant woman experiences shortness of breath and tachycardia attacks. Legs and face are very swollen. A woman puts on a lot of weight and may complain of pulling pains in her groin. The abdomen becomes very large and covered with stretch marks. General state of health - lethargic, weak; disturbed night sleep.

With severe oligohydramnios, the abdomen is small, the bottom of the uterus drops. Fetal movements are weak, hardly perceptible. The child suffers from oxygen starvation and underweight. In rare cases, drying of the skin of the baby and its fusion with the fetal membrane is possible. Most often, the fetus is in the breech presentation. If oligohydramnios is caused by leakage, a woman will notice a colorless discharge from the vagina.

When examining vaginal discharge (amniotest), placental protein is detected - a sure symptom of amniotic fluid leakage. Childbirth with a meager amount of water proceeds with complications: the cervix opens slowly, contractions are painful, labor is long. In case of full-term pregnancy and damage to the membranes, when there is leakage of water, the issue of inducing labor and artificial activation of labor is decided.

IAI does not correspond to the norm: what to do?

If a deviation of the IAI from the permissible values ​​is detected, a comprehensive examination of the expectant mother should be carried out in order to identify and eliminate the causes of the pathology. In cases where amniotic fluid is formed in excess quantities, it is important to normalize the proper nutrition of a woman and adjust her drinking regimen. A woman in labor will be prescribed a course of vitamins (C, E, B), preparations containing magnesium, and diuretics. In the presence of intrauterine infection, a course of antibiotic therapy is indicated.

Moderate oligohydramnios during gestation suggests a slight change in the volume of water. In this situation, it is enough for a woman in labor to adjust her diet and daily routine - in most cases, the AFI will increase to acceptable limits without harming the health of the fetus. A woman with severe oligohydramnios must be placed in a hospital to prevent complications in the baby. They carry out therapy for placental insufficiency and try to keep the fetus as long as possible so that it becomes ready for birth. When pregnancy is more than 33 weeks, a decision is made to stimulate labor.