What does 2nd trimester screening show? What influences the result? Planned ultrasound - video

For about 19 women, the doctor suggests a 2nd screening and ultrasound. These dates were not chosen by chance: at this time it is most convenient to study hormones. The first, as we remember, was in the middle of the 1st trimester of pregnancy. He usually shows that everything is fine. Indeed, at that moment it is possible to determine with accuracy only the fetus is developing correctly or not. Understanding what deviations from the norm mean at such a time is not easy. But on the 20th week, the results of screening can tell a lot. So, why is it worth doing second trimester screening, and is it worth the money spent on it?

Let's start with the fact that not all diseases are the result of external influence. Simply put, you can not protect the child from everything. There are diseases that begin as early as the first week of the intrauterine life of the fetus. For example, Down syndrome, which is formed at the time of crossing chromosomes, that is, even at conception. They are detected, for example, by screening or ultrasound. But nothing will help to avoid their appearance: here everything is in the hands of fate.

At the same time, it is not easy to raise a patient: not every family has the means and the desire to care for a baby with such deviations, because this is not just a cold. It's not even a disability. These are completely different children who grow up as completely different people who will not find it easy to settle down in this world. And they will only have you, the parents. Accepting that your child is “wrong” and accepting him as such is very difficult.

The results of the second screening and ultrasound performed during pregnancy give expectant parents a choice: if the child is sick, you can not give birth to him. It's not too late to have an abortion. True, the reliability of such a study is not too high and it often turns out that the child was actually healthy.

But back to the topic of screening. Let's figure out what screening is, what is its essence, what are the types of screening.

Screening is from the English "sifting". That is, the definition of a risk group in which the appearance of children with certain diseases is possible. Probabilities can be calculated according to different principles. The most famous screening program is PRISCA (Prenatal RISk Assessment) - perinatal risk assessment.

Basic analyzes

The standard timing for the 2nd screening is from 15 to 20 weeks of pregnancy. The later all the examinations are carried out, the more accurate the results will be. But it is also more dangerous to have an abortion. That's why optimal time for screening - 17-19 weeks of pregnancy. Your doctor will refer you to:

Biochemical screening of the 2nd trimester. It's a triple test. Here, blood will be taken from a vein and three components (AFP, hCG, estriol) of the blood will be checked for the presence of special markers. So it will be clear what the risk of diseases such as Down syndrome or Edwards syndrome is. This type of screening is completely safe as there is no effect on the mother's body. It's just blood.

Screening ultrasound. It's over accurate ultrasound than usual. It can be used to identify disorders such as heart disease, cleft upper lip or palate, diaphragmatic hernia, shortened bones, clubfoot, crossed fingers, and so on. These can be as minor deviations that can be cured with time, medicines or surgical intervention, and serious defects that will remain with the child for life.

Cordocentesis. It is not a mandatory part of the screening. But if any abnormalities were detected during ultrasound or examination, this procedure is desirable. Here, with the help of a special needle from the umbilical cord, the blood of the fetus will be taken in order to conduct more detailed examinations and obtain more accurate results. This method is not completely secure. In 2% of cases, a woman miscarries during pregnancy after this procedure. Often there are various hematomas and bleeding after the injection, but they pass quite quickly. In 1 case out of 100, an infection is introduced into the blood.

PRISCA often includes examinations such as cervical translucency calculation (calculated via ultrasound), measurement coccygeal-parietal size and many others.

Possible diseases

More often perinatal screening The 2nd trimester is spent to find out if the baby has some rare but equally frustrating medical conditions during pregnancy.

Down syndrome

As mentioned earlier, this disease appears even at the moment of chromosome crossing immediately after conception. Otherwise, Down syndrome is called trisomy 21, that is, the 21st pair of chromosomes is not a pair, but a trio. This is due to the fact that in the sperm or in the egg at the time of conception there was one extra 21st chromosome. The probability of this is approximately 1-1.5%.

The problem is that it is impossible to predict the appearance of this disease in a child in advance. It practically does not depend on the woman and the father of the child. The age of the mother only slightly affects the likelihood of the syndrome.

neural tube defect

The neural tube is formed in the embryo around the 20th day of pregnancy in the form of a plate. After a few more days, it should curl up into a tube. These terms are not very long, so the process goes almost unnoticed. The problem is that it can not close completely or turn around in the future, which can cause spinal defects. Unfortunately, it is difficult to immediately determine this violation at the beginning of pregnancy. By the middle of the 2nd trimester, that is, by the time of the 2nd screening, this defect can already be detected by ultrasound.

The result of this violation can be a cleft in the spine, a hernia and other neurological defects. 2nd biochemical screening allows you to notice these defects.

Edwards syndrome

The causes of this disease are the same as Down's syndrome. This is where trisomy 18 occurs. Such children are born late, but outwardly similar to premature babies. They are small, light, painful and weak. Numerous defects internal organs and parts of the body that can be seen on ultrasound. Such a child will not live long: a rare baby survives to his first birthday.

Fortunately, this syndrome is extremely rare: in 1 case out of 5000. But there is still a chance.

Screening results

The screening examination should take place on the same day. Then a few weeks will be checked and counted, and only then the results will be ready. Those are the deadlines. Biochemical screening of the 2nd trimester of pregnancy will show the level of three elements. What is the interpretation of the results?

This is a protein that the fetus itself produces, and not the mother's body during pregnancy. During the screening of the 2nd trimester, its percentage is accurately calculated. It enters the woman's blood in certain quantities. Any deviation from the norm means some kind of deviation in the development of the fetus.

According to PRISCA at 15-19 weeks of pregnancy, the level should be approximately 15-95 units / ml. The doctor will tell you more.

If a biochemical screening or ultrasound shows that your results are higher than normal, a spinal cord developmental disorder or defect is likely neural tube.

If the ACE level is much below normal, Down syndrome or Edwards syndrome, Meckel syndrome, occipital hernia, liver necrosis, spina bifida are possible. In this case, the 2nd screening is highly inaccurate. But it is not easy to notice these deviations on ultrasound.

The second screening for pregnant women is a comprehensive diagnosis necessary to identify possible pathologies and abnormalities in the development of the embryo. The procedure also helps confirm the results of the 1st screening. In this article we will talk about the timing, features of the preparation and the results obtained.

Screening translated from in English means "sifting", that is, the identification of women who are in " interesting position who are at risk. After completing this examination, if necessary, a woman can be sent for additional tests confirming or refuting the results of screening diagnostics.

The screening procedure is performed at specific stages of pregnancy. It includes:

Conducting an ultrasound examination performed on an expert-class apparatus is not by an ordinary doctor, but by a professional who is specifically involved in identifying any fetal malformations.
Testing to determine the amount of different hormones. At the 1st screening, as a rule, 2 hormones are determined, and in the case of the 2nd screening, the doctor must decide this issue based on each specific case.

When is the 2nd screening performed?

This diagnosis can be carried out for a period from 16 to 20 weeks of pregnancy. This time period is extremely important, especially for biochemical blood tests, since hormone levels do not remain stable, but constantly change. First, ultrasound diagnostics are performed, and then they are sent for blood donation.

Please note that many doctors believe that the most accurate results of the 2nd pregnancy screening can be obtained at 17 weeks.

The indications for the procedure remain the same as in the 1st trimester. Required in without fail carry out this examination in the following cases:

if the future parents are relatives;
a woman suffered an acute bacterial or viral pathology while pregnant;
the expectant mother has genetic disease capable of being transmitted to the baby;
one or both future parents suffer from a genetic (chromosomal) pathology;
earlier, a woman had miscarriages, childbirth took place before the due date;
the family already has a child with developmental anomalies;
one or more of the woman's pregnancies ended in the death of the fetus;

In addition, doctors will definitely refer you for the 2nd screening if:

on the first ultrasound examination(performed at 14 weeks and later), the presence of any developmental disorders of the embryo was revealed (if this happened for more than early dates, the woman will be sent for 1st trimester screening);
in the time interval from 14 to 20 weeks, the woman suffered an acute infectious pathology;
education was found various etiologies later than the fourteenth week.

In the last two situations, a pregnant woman will need to get advice from a geneticist, who will conclude how important full screening is in this situation. In some cases, doctors are limited to only repeated ultrasound diagnostics without a blood test.

What will this survey show?

Let us consider in more detail what exactly the specialist will determine during the second screening.

On ultrasound examination:

the length of the body of the fetus is determined, as well as the length of the bones;
head circumferences, chest and belly;
measure the nasolabial triangle;
it is possible to assess how symmetrically the facial structures develop;
the state of the structures of the skull and spine is determined;
diagnose the condition of the internal organs of the fetus, as well as maternal organs.

On biochemical screening, it is proposed to evaluate the performance of three or four hormones. So, the level of content in the blood of a pregnant woman of chorionic gonadotropin, inhibin A, unconjugated form of estriol and alpha-fetoprotein is detected. So, what should be the indicators of these hormones in the normal state:

1	Chorionic gonadotropin	Its normal amount in the blood at this time varies from 10 to 35 thousand mU / ml. At the same time, it is important not only to identify its amount, but also to compare its ratio with the amount of other studied hormones, namely, estriol and alpha-fetoprotein. It will also help identify possible pathologies.
2	Alpha fetoprotein	Most of this hormone is produced in the fetal liver. Alpha-fetoprotein has protective properties for the fetus, prevents the immune system of the pregnant woman from accepting the fetus as a foreign body
3	Estriol	The initial production of this hormone occurs in the placenta, and then estriol begins to be produced in the fetal liver with the participation of the adrenal glands. Estriol is important for preparing the uterus and mammary glands for the birth of a baby and the subsequent breastfeeding. The amount of the hormone gradually increases throughout pregnancy.
4	Inhibin A	This substance is necessary in order to prevent the maturation of new eggs during pregnancy. Hormone level in normal conditions should gradually decrease. Indicates Down's pathology increased amount inhibin A in the blood of a pregnant woman

So, for example, in the presence of Edwards syndrome, hCG levels are significantly lower than normal, and the level of fetoprotein also remains low. When improper development nervous system, chorionic gonadotropin will be normal at elevated level fetoprotein.

With a reduced amount of the hormone Alpha-fetoprotein, we can talk about the prerequisites for the development of Down syndrome, Edwards syndrome or intrauterine fetal death. An increased amount of alpha-fetoprotein indicates possible violations in the development of the neural tube, as well as on some organ pathologies gastrointestinal tract. The hormone should be assessed in conjunction with other data.

A significant increase in estriol may indicate multiple pregnancy or large fruit. The concentration of estriol may decrease due to various chromosomal pathologies.

Of course, the data obtained from a biochemical blood test are only an assumption of the presence of a particular disorder. There is no need to panic ahead of time or tune in to the bad, because for sure only a born child can be diagnosed, and everything else remains just a guess.

Features of preparation

As mentioned earlier, the 2nd screening includes two examinations: ultrasound diagnostics and a blood test for hormones.

There is no need for any special preparation for ultrasound examination. At this time, the intestines are pushed back due to the pressure of the enlarged uterus, and the bladder, which until then served as a window for ultrasound, is now replaced by amniotic fluid.

Unlike the first trimester, when ultrasound could be performed in two ways: by inserting a probe into the vagina or by applying it to the skin of the abdomen, only the last diagnostic option remains available in the second trimester.

Preparation is necessary for biochemical research. The day before donating blood, you should completely exclude the consumption of the following products:

chocolate (this includes all cocoa products);
citrus;
seafood;
overly fatty and fried foods.

On the day of the study, you need to refuse to eat at all for 4-6 hours. It is only allowed to drink ordinary water, which does not contain gas, but even then no more than 150 milliliters.

Video - second trimester screening

results

Some women face such an unpleasant situation that the 2nd screening shows poor results. Of course, this is very unpleasant and exciting, but still try not to panic. The results of the study indicate only a greater likelihood of occurrence various pathologies, but are by no means a 100% guarantee of this.

Be that as it may, if at least one deviation from the norm was established at the second screening, the pregnant woman will be sent for additional research without fail.

In addition, the test results may not be normal due to the influence of certain factors:

if the woman is pregnant naturally, but thanks to in vitro fertilization;
in the presence of overweight in a pregnant woman;
if there are different chronic pathologies(For example, diabetes and others);
If future mother does not give up addictions and continues to smoke, drink alcohol and so on.

You can add here one more thing that in the case of multiple pregnancy there is no point in carrying out biochemical research blood. Absolutely all indicators will be increased during the analysis, and doctors will not be able to calculate the risk of possible pathologies and developmental disorders. Ultrasound diagnostics carried out as usual.

Thanks to the second pregnancy screening, the woman and her doctor have the opportunity to receive information about the condition of the fetus, its development, as well as the course of pregnancy. It is mandatory to conduct a screening study in the first and second trimesters, and in the 3rd trimester this procedure is resorted to only if there are special indications.

Do not be afraid of this study - it will not cause any harm to either your health or the health of the little man.

Tip: Perform all screenings in the same laboratory, this will greatly simplify the process of deciphering the results for the doctor.

D to eat or not?

An unequivocal answer to this question, certainly does not exist. On the one hand, it is much better to detect serious developmental anomalies when the embryo is on initial terms and there is a possibility of termination of pregnancy. On the other hand, today the methodology is not sufficiently informative to make such a serious decision.

Therefore, everything is individual, the decision in any case is made by the parents, the doctor can only express his opinion on this matter. Another question is that you should not blindly believe the results obtained and you should always tune in only for the good.

Be that as it may, follow all the recommendations of your doctor and do not neglect routine examinations. They will help you avoid unpleasant situations so that the pregnancy ends with the birth of a healthy baby.

The second screening during pregnancy is carried out in order to identify birth defects and chromosomal pathologies that could not be detected at the 1st stage of the examination in the previous trimester. The range of studies includes ultrasound and biochemical analysis blood future mother. How many weeks are 2nd trimester screenings? How to prepare for it, how to take it and what does it show?

Features of the second screening

During pregnancy, 3 screenings are performed - one in each trimester. If the blood counts in the initial trimester of pregnancy were normal, stage 2 usually consists only of a planned ultrasound. However, if a woman is at risk, she needs to undergo a second full screening. A pregnant woman is included in this category if:

had problems bearing a child in previous pregnancies;
had a severe infection during the current pregnancy;
future parents are related by blood;
first screening revealed high risk congenital pathologies;
age over 35;
there is a long-term threat of miscarriage;
used medications prohibited during gestation;
the future mother and father, their older children have congenital diseases or malformations;
neoplasms were found.

What is the duration?

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The timing of the examination may vary from 16 to 24 weeks of pregnancy. There are some features here. The results of a blood test are considered the most accurate if the biomaterial was taken from 16 to 18 weeks. The timing of the passage of ultrasound according to the order of the Ministry of Health is from 18 to 21 weeks. Most often, in practice, the timing of the second screening is from 18 to 20 weeks. The exact date research is determined by the doctor leading the pregnancy.

What are they watching?

With the help of ultrasound of the 2nd trimester, which is more often done at a period of 20 weeks, the anatomical structure of the fetus is assessed for developmental anomalies and signs of hereditary diseases. The state and volume are determined amniotic fluid, fetal heartbeat, its mobility. They look at the parameters of the baby's body: the length of the bones of the upper and lower extremities, height, the size of the head and abdomen.

On ultrasound, the formation and location of the placenta, the number of vessels in it are determined. The doctor also evaluates the condition of the uterus, cervix and ovaries, the tone of the uterine walls.

The specialist checks the number of fingers, size, structure and maturity of the baby's organs. The structure of his facial bones, nose and hard palate is assessed.

Prescribed screening measures blood parameters such as alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG). AFP is a protein produced by the fetus. It transfers the necessary compounds to all organs and tissues of the baby, protects it from maternal immune system neutralizes estrogen. HCG is produced by the membranes of the fetus. It stimulates the synthesis of other hormones glucocorticoids and progesterone, supports the functioning of the placenta.

How is the research done?

Ultrasound examination of the second trimester does not require special preparation, however, the day before the procedure, it is recommended to refrain from fried and fatty foods, chocolate, citrus, cocoa. Blood is taken on an empty stomach, so it is better to prescribe an analysis on morning time. A couple of hours before the examination, it is recommended to refuse water. If the pregnant woman takes any medications, at the discretion of the doctor, their intake may be delayed.

For an ultrasound, the expectant mother lies on the couch and exposes her stomach. The procedure in the 2nd trimester is done transabdominally. On skin a special gel is applied, acting as a conductor between the device and the body. The transducer sends out sound waves that bounce off the tissues and return back. The signals are converted and displayed on the monitor screen, where the image is rendered. The specialist moves the sensor along the abdomen, takes the necessary measurements and records the information received. The procedure takes from 15 to 25 minutes, the result is issued immediately.

Norms and interpretation of results

Table. The second planned ultrasound, norms:

Gestational age	Abdominal circumference	Head circumference	Fronto-occipital size, mm	Biparietal size (head width), mm	Forearm bone, mm	Femur, mm	Humerus, mm	Leg length, mm	nose bones	amniotic index
16	88–116	112–136	41–49	31–37	12–18	17–23	15–21	15–21	5,4–7,2	73–201
17	93–131	121–149	46–54	34–42	15–21	20–28	17–25	17–25	5,4–7,2	77–211
18	104–144	131–161	49–59	37–47	17–23	23–31	20–28	20–28	6,6–8,0	80–220
19	114–134	142–174	53–63	41–49	20–26	26–34	23–31	23–31	6,6–8,0	83–225
20	124-144	154–186	56–68	43–53	22–29	29–37	26–34	26–34	7,0–8,3	86–230
21	137–177	166–200	60–72	46–56	24–32	29–37	29–37	29–37	7,0–8,3	88–233

Table. second screening, normal performance blood test:

The second screening helps to identify abnormalities in blood counts that may indicate abnormalities in the course of pregnancy and fetal malformations. Decoding is carried out by a doctor, if suspicious results are detected, the test is repeated. If you wish, you can take a screening test 2 times in a row - it is absolutely safe.

Causes elevated hCG can be: excess weight expectant mother, gestational diabetes mellitus, artificial insemination, multiple pregnancy. On the part of the fetus, the deviation can be caused by defects and genetic abnormalities. The indicator is reduced if there is a threat of miscarriage and miscarriage, there is placental insufficiency or developmental delay.

An increase in alpha-fetoprotein indicates a multiple pregnancy or a malformation of the brain - anencephaly. Another pathology that causes such a deviation is genetic anomaly of the spinal column, in most cases accompanied by developmental disorders of the spinal cord, more often in the form of a spinal hernia. Low rate may indicate chromosomal pathologies - Edwards or Down syndrome.

Why is a triple test needed in the 2nd trimester and how is it carried out?

A triple test is a set of studies that includes 3 analyzes. They also help assess the health of the baby. Such a test is prescribed in addition to the mandatory second ultrasound. Apart from hCG indicators and AFP, evaluate the level free estriol- This is a hormone that is responsible for establishing the relationship between the mother and the fetus. It is produced by the placenta, and later by the baby's liver. He takes part in placental circulation, progesterone production, preparation mammary glands to lactation.

For biochemical screening of the 2nd trimester, the biomaterial is taken from a vein, more often an ulnar vein. A tourniquet is applied 10 cm above the elbow. After that, the pregnant woman is asked to squeeze and unclench her fist several times to increase blood flow. The health worker determines the puncture site, disinfects and makes a fence. After that, a sterile napkin is applied. In order to stop bleeding and prevent bruising, the arm should be kept bent at the elbow for about 10 minutes. The analysis is performed using a computer, the result is prepared up to 14 days.

Normal estriol results on the second screening ( triple test) are given in the table:

High rates of free estriol are observed in multiple pregnancies and an increased level of oxytocin in the body of the expectant mother. Low values may indicate complications: chromosomal pathologies, hypoxia, fetal fading, growth retardation, placental insufficiency. Possible reasons downward deviations: diabetes mellitus, liver disease and anemia.

Quadruple test - what is it and why is it carried out?

The quadruple test, which is also carried out as part of the second screening, includes the same blood tests as the triple one, but one more indicator is added to them - inhibin A. This is a sex hormone that is always present in the body, but its level increases during pregnancy .

It is a marker of chromosomal pathologies (Down and Edwards syndromes), so its value is used to assess the risk of such congenital anomalies. The upper threshold value is 2 MoM, exceeding indicates a deviation. Low level inhibin A occurs when habitual miscarriage or other disturbances in the course of pregnancy.

How much does screening cost?

2nd trimester screening costs vary depending on where the study is being done. IN public institutions Ultrasound can also be done for free, but a biochemical test under such conditions is available only to pregnant women who are at risk. Commercial clinics set prices based on the quality of service, equipment and location (in large cities, the cost is usually higher).

The price is affected by the range of services to be done. Double screening (blood test) will cost less than triple or quadruple.

Biochemical screening, depending on the number of parameters evaluated, costs 1,000–2,000 rubles in Moscow. (data as of September 2018).

Throughout pregnancy, a woman needs to monitor not only her state of health, but also the hearth in order to identify possible pathology and accept necessary measures. For this purpose, there is a screening, which is carried out once a trimester. Screening is a study that includes the delivery of laboratory tests and diagnostic ultrasound that help determine congenital pathologies and fetal abnormalities.

The second screening during pregnancy is carried out in the second trimester of gestational age. Its purpose is to examine the fetus for the development of anomalies in various organs. In addition, it helps to refute or confirm the risks found at the first screening.

Timing of the second screening

The timing of the second screening during pregnancy varies from the beginning of the 16th week to the end of the 20th week of gestation. At this stage, it is possible to determine the amount of blood hormones. perfect time for the second screening - the 17th week of pregnancy.

Preparation for the event

The second screening during pregnancy does not require specific preparation. On the day of blood donation, no food or drink should be consumed except clean water, because the products can distort the results of the survey. Also the day before laboratory research you should refuse the following food: citrus, chocolate, seafood, soy, fatty and fried.

The results of ultrasound examination are not affected by the fullness of the intestine and Bladder so no preparation is required. The main rule for a future mother undergoing ultrasound screening is the absence of excitement and bad mood.

Conducting a second screening

The 2nd screening during pregnancy is not a strictly mandatory examination, but it helps to identify abnormalities in the development of the fetus. It is highly recommended to conduct this analysis for expectant mothers who:

there are deviations from the norm at the 1st screening;
burdened hereditary history;
age over 35;
there is habitual miscarriage;
there was infection during pregnancy;
there is a risk of miscarriage.

The first step in the second screening is ultrasound. On it, the doctor evaluates the fetometric parameters of the fetus and functional state his organs. Ultrasound determines the size of all bones, including the facial skull, lungs, heart, intestines and kidneys.

In addition, ultrasound evaluates the placenta, amniotic fluid and the umbilical cord, which also affect normal development future child. If all indicators of this examination are normal, biochemical screening may not be carried out.

In the presence of bad results screening, you should not immediately fall into despair, since this study cannot make an accurate diagnosis, additional diagnostics are needed, during which there is a possibility that the child will be healthy.

At the second stage, venous blood is taken. It determines the amount of three hormones: AFP (α-fetoprotein), E3 (estriol) and hCG (human chorionic gonadotropin). When taking blood tests, the expectant mother fills out a questionnaire.

Norms and interpretation of results

Laboratory results of the second screening during pregnancy reflect the development of the fetus. The studied hormones are produced by the placenta, respectively, their decrease or increase indicates a violation prenatal development.

Laboratory norms for indicators of the second screening during pregnancy

The second screening during pregnancy is deciphered by translating the results into an average value (MoM), which takes into account the age, constitution of the pregnant woman, and her place of residence. MoM = 1 is considered an ideal indicator, which means the minimum chances of pathologies in the fetus. The lower limit of the average values of the analysis for hormones is 0.5, the upper limit is 2. If the MoM indicator goes beyond the permissible values, a genetics consultation is necessary for the expectant mother.

An increase in hCG or MoM can talk about and Klinefeltr, a decrease - about Edwards syndrome. If AFP or MoM is higher than normal, there is a risk of neural tube defects. With reduced levels of this hormone, the fetus may show Down and Edwards syndrome. Elevated estriol and MoM are indicators of liver disease, and reduced ones are indicators of fetoplacental insufficiency, the threat of miscarriage and the absence of a brain in the fetus.

With an ultrasound examination, the doctor evaluates the size of parts of the fetus. Norms of fetometry of the unborn child:

Ultrasound also examines the bones of the facial skeleton, the structure of the heart, the organs of the digestive, urinary and respiratory systems. In the absence of their visible pathology, it is considered that the fetus is healthy. In addition, an assessment is made of the structure of the placenta, the umbilical cord, in which there should be 3 vessels. Also, with ultrasound, the volume of amniotic fluid is calculated (according to):

The last step Ultrasound at the second screening is an assessment of the uterus and its cervix. The length of the cervix is normally 3.5-4.5 cm. At lower values, the diagnosis of CI is made.

At normal values fetometry and AFI and the absence of visible pathologies of the organs, the fetus is considered healthy. If any abnormalities are detected during ultrasound, an in-depth diagnosis is required using invasive and non-invasive methods.