Amniotic fluid index at 20 weeks. Associated symptoms of pathological abnormalities in the volume of amniotic fluid

Amniotic fluid (amniotic fluid) is a biologically active liquid medium that surrounds the fetus during pregnancy. It consists of water and contains small amounts of mineral salts, fetal cells, fragments of sebaceous glands and epidermal scales. Education amniotic fluid begins in the third week of pregnancy and reaches 1-1.5 liters by the time of birth.

Amniotic fluid not only allows the baby to move freely in the womb, but also maintains a constant body temperature and protects it from infection and mechanical influences from the external environment. Towards the end of pregnancy, the kidneys and lungs of the unborn child begin to take part in the production of amniotic fluid.

Amniotic fluid analysis

Diagnosis of amniotic fluid is divided into invasive and non-invasive. The second group includes one method - ultrasound. During ultrasound examination The doctor can determine the amount and index of amniotic fluid (AFI).

Invasive diagnostics of amniotic fluid includes:

Amnioscopy. During amnioscopy, a tube with a flashlight (amnioscope) is inserted into the cervix. When illuminated amniotic fluid you can examine their color and consistency, as well as the presence of blood or feces in them. Amnioscopy is performed after 37 full weeks pregnancy.

Amniocentesis. Amniocentesis is the collection of fetal fluid by puncture of the amniotic membranes. The puncture is carried out through abdominal cavity, either through the vaginal wall or cervix. With amniocentesis, it is possible to determine the composition of amniotic fluid and thereby identify pathology in the unborn child. Performed according to indications after 16 weeks. After taking amniotic fluid, bacteriological, histological, cytogenetic, and biochemical analyzes are performed.

Amniotic fluid index and its norm

Amniotic fluid index (AFI)- This is an indicator of the amount of amniotic fluid at a specific stage of pregnancy. The study helps to establish a decrease and increase in the amount of amniotic fluid.

The change in IAF has a certain pattern. From the beginning of pregnancy to the 27th week of gestation, the amniotic index gradually increases and averages 156 mm, then it declines. The amniotic fluid index is reduced by approximately 10 mm compared to week 27.

The amniotic fluid index at 37 weeks, which is very close to childbirth, decreases by another 10 mm. Immediately before the birth of the child (38-40 weeks of gestation), a final decrease in the amniotic fluid index is observed to an average value of 125 mm.

Attention! Routine ultrasound and determination of AFI help to timely diagnose abnormalities in the amount of amniotic fluid and prescribe effective treatment to prevent various pathologies in the unborn child.

The amniotic index is determined using ultrasound in two ways: subjective and objective. The first method is based on the fact that during an ultrasound examination, the doctor scans the uterus in all planes and visually notes the volume of amniotic fluid. If there is a large accumulation of amniotic fluid between the fetus and the abdominal wall, a diagnosis of “polyhydramnios” is assumed, and if there is a small accumulation – “oligohydramnios”.

Objectively, the amniotic fluid index is determined by dividing the uterus into 4 squares, the vertical axis of the marking passes through the center of the abdomen, the horizontal through the navel. In each quarter, the maximum pocket is determined - the space where amniotic fluid is located without a child. Next, these indicators are summed up and the amniotic index is displayed - the result of adding the obtained values.

Norms of amniotic fluid index by week in table form

Oligohydramnios during pregnancy

Oligohydramnios is a pathology in which the AFI value is less than the lower normal value. The reasons may be:

renal pathologies of the fetus;
somatic diseases in a pregnant woman (chronic heart failure, chronic obstructive pulmonary disease, etc.);
urogenital infections;
smoking and alcoholism;
placental diseases;
bearing twins;
aging of the placenta during postmaturity.

Oligohydramnios is divided into 2 types: moderate and severe. In the first option, if fetal CTG is normal, treatment is not carried out, however expectant mother should monitor your diet, amount of fluid consumed and sleep patterns.

When fetal oligohydramnios is severe or there are abnormalities on CTG, symptomatic therapy is used:

Vitamins.
Drugs that improve blood supply to the placenta (Curantil, Actovegin).
Antibiotics.

If conservative therapy is ineffective, the issue of premature delivery is resolved.

Polyhydramnios during pregnancy

Polyhydramnios is a pathology in which the AFI value is greater than the upper normal value. The reasons may be:

somatic diseases of the expectant mother (diabetes mellitus);
infection during pregnancy;
Rhesus conflict;
congenital anomalies;
increase in the weight of the unborn child.

For the treatment of polyhydramnios, vitamin therapy, diuretics (Furosemide), antibiotics, and drugs to improve blood circulation in the placenta (Curantil, Actovegin) are used.

During treatment, constant monitoring of the fetal condition using CTG is necessary, since with this pathology there is a possibility that unborn child gets tangled in the umbilical cord. If conservative therapy is ineffective, amniocentesis is used - taking a small amount amniotic fluid, or premature delivery.

Violation of the formation and absorption of amniotic fluid threatens oligohydramnios. Let's take a closer look at this concept.

What is oligohydramnios?

In obstetrics and gynecology, insufficient amniotic fluid 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 included in the water), from mechanical influences from the outside (for example, from blows 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 mommy is healthy and her body temperature does not exceed 37.8 ºС);
exchange function– the child absorbs amniotic fluid, enriched with nutrients, and releases it back.
In addition to all this, fetal fluid ensures free movement of the baby inside the womb. Therefore, with a normal amount of amniotic fluid, the baby is cozy and comfortable, he is protected and provided with everything he needs.

What does amniotic fluid contain?

As pregnancy progresses, the composition of the amniotic fluid changes and becomes more varied and rich, making the waters slightly cloudy in appearance. Amniotic fluid is secreted by cells of the aqueous 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 liquid is supplemented by dead skin cells (as a result of the natural process of replacing the old layer of skin with a new one), fetal fluff (hairs), vernix cheese-like lubricant of the fetal body and waste products (sterile urine).

The fetal waters are renewed every 3 hours.
Drinking water has no effect on the amount of amniotic fluid. Excessive fluid intake will only cause swelling in a pregnant woman.

Normal amount of amniotic fluid

If the amount of amniotic fluid deviates from the norm, doctors diagnose oligohydramnios or polyhydramnios. The amount of fluid is determined by a diagnostician during an ultrasound scan, starting from the second trimester of pregnancy.

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

Table - Norm of amniotic fluid index by week

The standards 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 fluid is characterized by another indicator - the vertical size of the largest (free) water pocket (WC). 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 low water - 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.

You can often find an inscription in an ultrasound report: “a tendency towards moderate oligohydramnios.” This means that the expectant mother may have health problems and needs more careful monitoring.

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

Moderate lack of water is not a critical situation, because the amount of water is not constant and can change several times a day. Perhaps there was an error in establishing the diagnosis and the fault was with the doctor who made a not very accurate calculation during the ultrasound, because determining the amniotic fluid index is a subjective and approximate matter. Therefore, there is no need to panic; in 8 out of 10 cases, pregnancy ends in the 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 monitoring 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 fetal urinary system (kidneys, for example);
leakage of amniotic fluid (if the integrity of the membranes is violated);
pathology in the development of membranes;
bacterial infections suffered during pregnancy or shortly before its onset;
diabetes;
late gestosis.

Most often, oligohydramnios occurs due to metabolic disorders in a pregnant woman, as well as after viral diseases (acute respiratory infections, acute respiratory viral infections, etc.) and with fetoplacental insufficiency.

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

The only thing is that childbirth with oligohydramnios (even slight) can occur with some complications (poor opening of the cervix, painful contractions and prolonged labor due to pelvic 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 post-term pregnancy is considered a common occurrence, since the placenta has grown old and can no longer fully perform its functions, so it exfoliates. Then doctors prescribe induction of labor or carry out planned C-section.

How dangerous is oligohydramnios for the fetus?

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

For example, when the integrity of the membranes is lost - this is when amniotic fluid leaks - the child becomes vulnerable to infections entering the membranes.

A woman’s reproductive tract is not sterile, pathogenic microorganisms constantly live in the vagina, “plus” the immune system is weakened due to pregnancy. All this can lead to the proliferation of harmful bacteria, which can penetrate inside the uterine cavity and infect the membranes, causing inflammation, called chorioamnionitis in gynecology. Without timely treatment, the fetus itself becomes infected.

This applies to oligohydramnios caused by a violation of the integrity of the membranes.

With severe oligohydramnios, regardless of the reasons for its occurrence, the baby suffers from hypoxia (lack of oxygen), because of this he lags behind in intrauterine development. In addition to all this, it is uncomfortable for the baby to be in such a “nest”; his neck is often curved, and the bones of the face and head are susceptible to deformation due to compression 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 gaining body weight (so-called malnutrition is observed), his muscle tone is reduced (possible development of torticollis, clubfoot), and mild fetal hypoxia occurs.

If screening and urine/blood/smear tests are normal, the cardiotocogram (CTG) is normal and the fetus is developing well, and the pregnant woman has no complaints about her health, then the diagnosis of oligohydramnios is conditional. Obstetricians will simply prepare to induce labor, since there is a high probability of a post-term pregnancy, or for a cesarean section if the fetus is not in a standard position at the due date.

Diagnosis of oligohydramnios

During 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 assume low or high hydramnios at the next measurement of the abdominal circumference and the height of the uterine fundus, but a more accurate diagnosis can only be made with the help of an ultrasound.

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

The test can be carried out at home by observing the discharge for some time, or by purchasing a special test for leakage of amniotic fluid at the pharmacy and using it.

The “free” test is carried out like this: empty bladder, take a shower (without douching and possible water getting inside the vagina), wipe yourself dry with a towel and lie down on a dry diaper. Lie motionless for 15 minutes, and then get up and see if a wet spot appears on the diaper. Normal discharge is not capable of forming and flowing out so quickly; most likely, it is amniotic fluid leaking. You can find out more accurately by contacting the LCD with a complaint about unusual discharge. There they will conduct a special test and say it is water or normal vaginal discharge.

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

Coloring also occurs with bacterial/viral discharge, so if you notice blue-green spots on the surface of the pad, contact your gynecologist.

Any test for leakage of amniotic fluid is recommended to be carried out 12 hours after the last sexual intercourse, douching or use of vaginal suppositories.

Treatment of oligohydramnios

It is impossible to artificially increase the amount of amniotic fluid, so treatment of oligohydramnios comes down to determining the causes of its occurrence. Next, the root causes of oligohydramnios are treated.

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

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

Moreover, Curantil is often prescribed as a measure to prevent fetoplacental insufficiency.

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

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

Childbirth with oligohydramnios

In case of severe oligohydramnios, a planned caesarean section is prescribed. With a small volume of amniotic fluid, the fetal bladder becomes flat view. Because of this, contractions will be irregular and weak, and labor may be long and difficult.

Moderate oligohydramnios is not a contraindication for natural birth. Even with pelvic or breech fetus caused by oligohydramnios, the birth proceeds safely for both the mother and her child.

An insufficient amount of amniotic fluid does not allow the baby to move freely inside the womb. Therefore, the child often takes a transverse or buttock position and can no longer roll over correctly.

There are various exercises that can help turn the baby into the desired position, but their effectiveness has not been confirmed from a medical point of view. Exercise can lead to umbilical cord entanglement, so you need to weigh the pros and cons before doing it.

A very important role in normal course During pregnancy, the composition of the waters around the fetus and their sufficient quantity play a role. There are several ways to determine these parameters. The most reliable is the establishment of the amniotic fluid index in cm.

In order for the ultrasound doctor to be able to provide the most accurate information regarding the study of amniotic fluid, modern ultrasound machines are equipped with special programs that contain tables of amniotic fluid norms and automatically calculate the required index. The results of such an analysis show such pregnancy pathologies as polyhydramnios or.

Determination of amniotic fluid norm

Objective definition. The uterus is scanned in all sections and the ultrasound machine automatically calculates the indicator.
Subjective definition. Ultrasound is also used, but during the study the readings of the maximum upper quadrants of the uterus are summed up, which will equal the amniotic fluid index.

The numbers obtained as a result of ultrasound examination are compared with the table of amniotic fluid. It is worth noting that each device is equipped with its own version of the table, the components of which may differ significantly, however, there is a more or less average version. Index values become the basis for establishing diagnoses such as polyhydramnios or oligohydramnios. However, they are not a guide to decisive action, since the doctor will determine many more related factors.

Amniotic fluid index by week

During the entire period of gestation, amniotic fluid constantly changes its quantitative and qualitative composition in direct proportion to the duration of pregnancy and the growth of the baby. With each week, the volume of fluid steadily increases by an average of 40-50 ml and can reach 1-1.5 liters before delivery itself and may decrease slightly. However, a one-time estimate of the amount of water cannot be reliable, since the fetus is constantly changing position.

An approximate table of amniotic fluid contains data on the normal volume of amniotic fluid for each week of gestation and maximum permissible deviations from generally accepted indicators.

In order to talk about actual polyhydramnios or amniotic fluid deficiency, it is necessary to determine the exact deviation from generally accepted norms, which do not fit into the extreme limits acceptable indicators. So, for example, if the amniotic fluid index of 11 cm occurs at the 32nd week of gestation, then there is no reason for concern. But the presence of such a volume of water at the 22nd or 26th week already indicates their excess.

Knowing the indicators of the amniotic fluid table depending on the gestation period will help the expectant mother independently understand the results of the study if she has not received objective explanations from her gynecologist. Neglecting the results of an ultrasound examination is fraught with complications in the process of getting rid of the burden, and exactly.

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Water is the first thing a child gets acquainted with. While still in the womb, it floats in a fluid called amniotic fluid. Find out what amniotic fluid looks like and what the norm is by week (table) of pregnancy from the article.

Why amniotic fluid is needed

Amniotic fluid is necessary for the normal development of the child in the mother's womb; it is needed for

protecting the child from loud sounds and impacts (water absorbs noise and acts as a shock absorber);
maintaining a comfortable temperature (amniotic fluid has a temperature of 37 degrees);
protection from external threats (the amniotic fluid bladder is sealed, which allows the child to be protected from external influences);
providing nutrition to the baby (water does not allow the bladder to shrink, preventing the umbilical cord from being compressed);
freedom of movement of the baby (in the 1st-2nd trimester the baby can move freely and swim in the amniotic fluid).

At birth, leaving his native environment, the child experiences stress, which water helps relieve. When the birth ligament is washed off from a newborn baby, he relaxes. This is very important for preparing for the new stage of his life.

Composition and norm of amniotic fluid

The fetal membranes begin to form after the fertilized egg attaches to the wall of the uterus. Then a complex process begins. A protective bladder with sterile fluid inside is formed from the membranes (amnion and chorion). As the fetus grows, the bubble enlarges.

Amniotic fluid is formed due to the “leakage” of maternal blood plasma. On later The child himself, his lungs, and kidneys also participate in the production and renewal of amniotic fluid.

Amniotic fluid consists of water (97%) with proteins and mineral salts (calcium, sodium, chlorine) dissolved in it. Skin cells, hair cells, and aromatic substances can also be found in it.

There is an opinion that the smell of amniotic fluid is similar to the smell of mother's milk, so a newborn baby can easily find his mother's breast, because he drank a liquid similar to milk in the womb.

Norm and pathologies

The normal amount of amniotic fluid at the end of pregnancy is 600-1500 ml. For a number of reasons, these figures may deviate more or less from the norm. Then doctors talk about polyhydramnios or oligohydramnios.

Oligohydramnios is diagnosed when the expectant mother has less than 500 ml of amniotic fluid. The reason for the decrease in the amount of water lies in the insufficient development of the endometrium (water membrane) or a decrease in its secretory ability. Among other reasons, causing pathology, called

abnormalities in the development of the child’s genitourinary system;
mother's hypertension;
inflammatory diseases women;
metabolic disorders, obesity;
fetoplacental insufficiency.

Oligohydramnios in one fetus when carrying twins is explained by the uneven distribution of blood in the placenta.

With oligohydramnios there are severe pain in a stomach, painful movements child, the uterus is reduced, the size of its fundus does not correspond to the period of pregnancy.

With polyhydramnios, the secretory function of the aqueous membrane is increased. Polyhydramnios can result from:

diabetes mellitus, infectious and viral diseases of the mother;
heart disease, kidney disease;
incompatibility of the Rh factor of the blood of mother and child;
multiple pregnancy(polyhydramnios in one fetus, oligohydramnios in another);
diseases of the placenta.

Signs of polyhydramnios are heaviness in the abdomen, swelling of the legs, breathing and blood circulation become difficult, and the child’s movements become too active.

Oligohydramnios and polyhydramnios are dangerous pathologies. To eliminate them, the help of a specialist is required. At the slightest suspicion, you should consult a doctor.

Deviations in the color of amniotic fluid

Normally, amniotic fluid is colorless and transparent. The consistency is similar to water and has no odor. Most often, expectant mothers are concerned about changes in the color of the amniotic fluid.

You can judge the color of amniotic fluid during its outpouring, which occurs during childbirth. In most cases, if the pregnancy is full-term, the waters are clear or cloudy yellow. This is their normal color and is not dangerous. The woman’s task after her water breaks is to get to the maternity hospital within 2-3 hours.

Amniotic fluid may be a different color.

Red speckled. A slight admixture of blood in a fluid of normal (light or cloudy yellow) color is considered normal, since it indicates dilatation of the cervix.
Green color. The baby's original feces turn the water greenish or swampy. The child experiences oxygen starvation; swallowing such water is dangerous for the development of pneumonia in the baby.
Red. Dangerous color indicates internal bleeding in the mother or fetus. The best decision is to take a horizontal position and urgently call an ambulance.
Dark brown. This color indicates the death of the fetus; you should immediately consult a doctor.

If the color of the amniotic fluid changes, the mother and baby may be in danger. Therefore, it is better not to get to the maternity hospital on your own; you should call an ambulance and report the color of the water.

Water research methods

Today, there are several ways to obtain information about the state of the amniotic fluid before the onset of labor. All methods are divided into invasive (requiring direct sampling of material) and non-invasive (not requiring penetration into the uterine cavity).

The only non-invasive method is ultrasound. This study can provide information about the amount of amniotic fluid and allows you to diagnose oligohydramnios or polyhydramnios.

Other research methods (invasive) are associated with high risks, therefore they are carried out for serious indications.

Amnioscopy. Inspection of amniotic fluid using an amnioscope. This device is a tube with a lighting device at the end. The examination of the expectant mother is carried out on a gynecological chair by inserting the device into the cervix. The doctor pays attention to the color and consistency of the water. An examination is possible after 37 weeks if there is a suspicion of fetal hypoxia or Rhesus conflict.
Amniocentesis. Unlike amnioscopy, amniocentesis is performed after 16 weeks of pregnancy, when the fluid volume reaches 150 ml. A needle is inserted into the amniotic cavity under ultrasound guidance and a small amount of fluid is withdrawn. To perform amniocentesis, serious indications are needed: suspicion of genetic diseases or intrauterine infections, Rh conflict, insufficient oxygen supply, chronic diseases of the mother.

Invasive diagnostic methods are associated with risks of miscarriage, premature rupture of amniotic fluid, miscarriages, and placental abruption. Only a doctor can prescribe the procedure.

Amniotic fluid norms by week of pregnancy

As pregnancy progresses, the amount of amniotic fluid increases. Approximate calculations look like this:

30 ml at 10-11 weeks;
100 ml for 13-14;
400 ml at 17-20;
1200ml for 36-38;
600-800 a few days before birth.

The amount of amniotic fluid is individual for each expectant mother; the calculations given are approximate, so doctors do not measure the amount of amniotic fluid in milliliters using the definition of “amniotic fluid index.” It is measured using an ultrasound machine starting at 16 weeks. The norms look like this:

73-201 mm (average 121) at 16 weeks;
77-211 (127) at 17;
80-220 (133) by 18;
83-230 (137) at 19;
86-230 (143) by 20;
88-233 (143) at 21;
89-235 (145) at 22;
90-237 (146) at 23;
90-238 (147) by 24;
89-240 (147) at 25;
89-242 (147) at 26;
85-245 (156) at 27;
86-249 (146) at 28;
84-254 (145) at 29;
82-258 (145) at 30;
79-263 (144) at 31;
77-269 (144) at 32;
74-274 (143) at 33;
72-278 (142) at 34;
70-279 (140) at 35;
68-279 (138) at 36;
66-275 (135) at 37;
65-269 (132) at 38;
64-255 (127) at 39;
63-240 (123) by 40;
63-216 (116) at 41;
63-192 (110) at 42.

These figures can be seen in the medical card; the average figures for each stage of pregnancy are given in brackets. Only a doctor can correctly decipher the data, since the norms of the amniotic fluid index depend on individual characteristics body.

Leakage of amniotic fluid

You can determine the leakage of amniotic fluid at home. There is a special test pad for this. The method is quite popular, but such a gasket is quite expensive (400-600 rubles), and the result is not always reliable. So, not only leaking water, but also inflammatory diseases can show a positive result.

The exact result can be obtained in the maternity hospital after examining the discharge.

The most informative way to determine water leakage is amniocentesis. A safe dye is injected into the amniotic sac using a needle, and a tampon is placed in the pregnant woman's vagina. Dyeing the swab will show leakage of amniotic fluid. This method is used in special cases when the child's life is at risk.