Severe heartburn than to treat at home. How to treat heartburn: why it appears and what is recommended to take as an emergency

If the pregnancy proceeds without complications, the mother feels well, then for the first time she will be able to look at her baby during the first screening at about 12 weeks of pregnancy. We will talk about what a screening study is at this time in this article.

What it is?

There are three screenings for pregnancy. The very first Ministry of Health is recommended to be carried out for a period of 11-13 weeks, the 12th week is considered optimal. Then the screening study takes place in the second and third trimesters (at 16-24 weeks and at 30-36 weeks).

An examination that is carried out at the very beginning of the process of bearing a baby includes ultrasound, as well as biochemical blood test for the content of the hCG hormone and PAPP-A protein. According to a number of characteristic markers that are found in the ultrasound diagnostic room, as well as the concentration of hormones and proteins in the analyzes of a pregnant woman, a preliminary calculation of the risks of a baby with incurable and fatal genetic pathologies in this woman is made.

This stage of prenatal diagnosis allows you to identify women who are most likely to have a baby with Down syndrome, Turner and Cornelia de Lange syndromes, Patau syndrome, Edwards syndrome, gross neural tube defects, as well as other developmental anomalies that do not leave the slightest chance for a cure. and normal life.

Previously, screening was done only for those pregnant women who are at risk - women who are already 35 years old and older, who became pregnant from a blood relative, those who have previously had children with genetic problems, or women who have relatives with hereditary diseases on your own or your husband's side. If the expectant mother took medications that are prohibited during early childbearing, she was also prescribed a screening study.

Now this diagnosis is prescribed to all, without exception, the fair sex in an “interesting position”. Of course, a woman may, for personal reasons, refuse screening, but it is not entirely reasonable to do this, because the examination itself does not oblige anyone to anything.

It should be noted that based on the results of screening during pregnancy at 12 weeks, no one will make any diagnoses. This is outside the scope of the screening study. A woman will only calculate the individual risks of giving birth to a sick baby, and whether they are healthy can be established by other methods that will be recommended by an obstetrician and geneticist if the risks are high.

The first screening is considered the most important and informative. It is carried out free of charge in a consultation at the place of residence, referrals for a blood test and a ticket to the ultrasound room are issued by the doctor to whom the woman was registered for pregnancy.

Procedure and preparation

When undergoing a perinatal examination in the first trimester, it is very important to follow a strict procedure. Ultrasound diagnostics and blood donation from a vein are planned for one day so that the time interval between these two actions is minimal.

Usually, they first undergo an examination in the ultrasound room, and then, with the completed form, they go to the treatment room to donate blood. However, in some consultations the order is reversed. In any case, both examinations are carried out strictly on the same day.

So that the test results are not affected by negative factors, which include biochemical changes in the blood, the accumulation of gases in the intestines, a woman is recommended carefully prepare for the diagnosis. For two days, you should go on a short diet - do not eat fatty and very sweet foods, fried and smoked, six hours before the blood test you should not eat at all. A blood test is taken on an empty stomach.

Before an ultrasound scan, you should take Smecta or Espumizan for a couple of hours to get rid of intestinal gases, which are faithful companions of pregnancy, since they can put pressure on the pelvic organs and the ultrasound results may be inaccurate.

Ultrasound at 12 weeks is performed with a transvaginal probe; the second method is on the stomach, until it gives a clear picture and idea of ​​\u200b\u200bwhat is happening inside the uterus.

On the appointed day, the woman comes to the office of her obstetrician-gynecologist, is weighed, her height is measured and a detailed questionnaire is filled out. The more data it contains, the more accurately the risks will be calculated. The questionnaire includes data on previous pregnancies, miscarriages, abortions, the age and weight of the woman, data on her bad habits (smoking, alcohol), information about her husband and the health status of close relatives.

Then there will be an ultrasound, and then blood donation. The general results will be entered into a single form, a special program will “compare” the genetic portrait of the pregnant woman, along with her analyzes, with the “portraits” of women at high risk of giving birth to a sick baby. As a result, an individual calculation will be issued.

Ultrasound procedure

In the ultrasound room, the doctor will examine the baby, determine if everything is fine with him, in which place of the uterine cavity he is fixed, and also check the baby for markers that show a high probability of having a child with genetic syndromes. At week 12, the expectant mother will be able to see her baby, listen to how his little heart beats, and also see the movements of the fetus, which she does not yet physically feel.

The doctor in the protocol of the screening study of the first trimester must indicate how many fetuses are visualized in the uterine cavity, Do they show signs of life? and also describe the main dimensions that will allow you to clarify the timing of the "interesting situation" and find out how the development of the crumbs proceeds.

The indicators of the norm of development at 12 weeks are as follows:

Fetal head circumference (OG) - 58-84 mm, most often - 71 mm.

The coccyx-parietal size (KTR) is 51-59 mm, most often 55 mm.

The biparental head size (BDP) is 18-24 mm, most often 21 mm.

Heart rate (HR) - 140-170 beats per minute.

Motor activity is present.

In addition, the doctor determines the two most important markers for diagnosing genetic pathologies - the thickness of the collar space and the presence of nasal bones in the baby. The fact is that in children with gross malformations, the cervical fold is enlarged due to subcutaneous fluid (swelling), and the nose is flattened. He will be able to examine the rest of the facial bones only after one and a half to two calendar months.

TVP (nuchal thickness) at 12 weeks in the absence of pathologies does not go beyond the range of 0.7-2.5 mm. If the baby has this parameter slightly exceeded, the expectant mother may be advised to undergo an ultrasound scan again in a week. If TVP significantly exceeds the upper limits of the norm, an additional examination will be required, the risks of giving birth to a sick baby increase. We are talking about an excess of 3.0 mm and above.

Nasal ossicles can be much more difficult to see, they are not always visualized at 12 weeks, the fetus can settle down to the doctor’s sensor with its back and stubbornly refuse to turn around and let your nose be measured. If it was possible to do this, the normal values ​​of the length of the bones of the nose at this time are those that do not go beyond the limits of the range of 2.0-4.2 mm.

If the doctor indicated that at 12 weeks these bones are not visualized or their size is less than 2 mm, the risk-calculating program will increase the individual probabilities of having a baby with Down, Turner, Patau syndrome.

In fact, the baby may just have a small miniature nose, which is still difficult to capture in a numerical value, especially on an old ultrasound scanner with poor image clarity.

Theoretically, at 12 weeks, you can already try to determine the sex of the child, because the external genitalia are formed, and if the baby is conveniently located and open to the eyes of the diagnostician, they may well be noticed. However, you should not expect guarantees from the doctor that it is a boy or a girl who will be born. Sex at this time can only be named presumably (the probability of an accurate hit is approximately 75-80%). More precisely, the doctor will assess the baby's sexual characteristics at the next ultrasound, after 16-17 weeks of pregnancy.

Additionally, ultrasound at the end of the first trimester evaluates the likely threats of interruption of gestation - thickened uterine walls may indicate the presence of hypertonicity, as well as the condition of the cervix, fallopian tubes, and cervical canal.

Blood chemistry

In the analysis of the venous blood of a pregnant woman, the laboratory assistant detects the amount of the hCG hormone and plasma protein PAPP-A contained in it. Because only two blood components are evaluated, the first screening test is called a "double test". The results of this study, in contrast to the ultrasound data that a woman is given immediately after passing, will have to wait from several days to several weeks - it depends on how long the queue lined up for the study in an accredited medical genetic laboratory.

What the numbers will be as a result of the analyzes, one can only guess, since individual laboratories use their own norms in the calculations. To simplify the decoding, it is customary to talk about the norm of PAPP-A and hCG in MoM - a value that is a multiple of the median. In a healthy pregnancy, when both the child and the mother are doing well, both values ​​“fit” within the range from 0.5 to 2.0 MoM.

Fluctuations from this range up or down give rise to a lot of experiences in pregnant women and many possible reasons:

Increasing hCG."Busting" on this indicator can be a sign of Down's syndrome in a baby, as well as a sign that a woman is carrying more than one child. 2 fruits together give a practical double increase in the rate of the hormone. Elevated hCG may be in a woman who is overweight, edema, toxicosis, diabetes and hypertension.

Decrease in hCG. An insufficient level of this hormone, which is inherent only in pregnant women, is characteristic of the development of Edwards syndrome, and can also indicate the likelihood of a miscarriage or a delay in the development of the baby.

Every pregnant woman at a certain stage of bearing a baby is faced with such a concept as screening. What it is? Screening is a comprehensive examination that gives an idea of ​​the health and development of the fetus, and also allows you to determine the likelihood of a child being born with congenital malformations. Such examinations are carried out every trimester, respectively, three trimesters of pregnancy involve the passage of three screenings.

The first screening during pregnancy makes it possible to identify among expectant mothers those who are at risk of having a child with chromosomal abnormalities and hereditary diseases. Every pregnant woman should read the information: what is included in the screening of the 1st trimester, for how long it is usually carried out, what are the standards for screening of the 1st trimester and what to do if the examinations show poor results.

Timing and indications for the first screening

First trimester screening can be considered reliable if performed between weeks 11 and 14. It will be optimal to do screening at 12 weeks of pregnancy. It is for this reason that it is very important to register for pregnancy before this date. The best time to perform a 1st trimester screening should be determined by the gynecologist who manages the woman's pregnancy. It is still not too late to do screening at 13 weeks of gestation, but its results will still be less reliable. It is also worth noting that perinatal screening performed in the first trimester of pregnancy will be more informative than screening in the second trimester.

1 pregnancy screening is not mandatory, but medical professionals advise not to neglect this examination if a woman wants to be well aware of the health status of her unborn child. Among pregnant women, there are certain risk groups. If a woman belongs to one of these groups, then the doctor will strongly recommend that she undergo 1st trimester screening:

• the pregnant woman had two or more spontaneous abortions (preterm birth);
• the woman experienced a missed pregnancy or stillbirth;
• during pregnancy, the expectant mother suffered a viral or bacterial disease;
• among family members there are people with genetic pathologies;
• the woman already has a child with chromosomal abnormalities or severe genetic diseases;
• the woman was treated with drugs that are prohibited for pregnant women;
• the age of the woman is more than 35 years;
• the child's father is a blood relative of the pregnant woman.

The first pregnancy screening is quite informative in terms of identifying the following pathologies:

• anomalies of the neural tube (rudiment of the central nervous system);
• Smith-Opitz syndrome;
• Cornelia de Lange syndrome;
• omphalocele (umbilical hernia, manifested by the fact that some of the internal organs of the fetus are not in the abdominal cavity, but in a hernial sac that emerges on top of the skin).

Each pregnancy is individual, which means that screening for different women can take place in different ways. It will be enough for someone to pass the necessary tests once and no longer worry throughout the pregnancy. Others are prescribed the same examinations several times. It is worth noting that negative results are not yet a reason for panic. You need to take them as a signal that more careful monitoring of the course of pregnancy is required.

How is first trimester screening done? This examination includes an ultrasound examination (ultrasound) of the fetus and a biochemical analysis of the mother's blood.

first trimester ultrasound

Ultrasound has long been a universal method by which all pregnant women are examined. The technique is simple to perform, informative and does not pose a threat to the health of the mother and fetus. For a long time using the procedure, experts have not found any harm from the effects of ultrasound on the development of the fetus. In obstetrics, two types of ultrasound are used for the 12th week of pregnancy:

• Transvaginal (a specialist inserts an ultrasound probe into the vagina);
• Abdominal (to obtain an image, the sensor is driven along the mother's stomach).

How to prepare for an ultrasound? Special preparation for an ultrasound examination at 12 weeks of gestation is not required. It would be desirable for a pregnant woman to drink about 500-1000 ml of non-carbonated water, since the amount of amniotic fluid during this period of pregnancy is still insignificant, namely, amniotic fluid makes it possible to examine the fetus as well as possible. Also, a day or two before the examination, it is better to exclude foods that can increase the formation of gases in the intestines. Excess gases can distort diagnostic results.

Up to 10 - 11 weeks of pregnancy, a fertilized egg has an extremely small size - from 2 to 4 mm. The maximum that an ultrasound specialist can detect in the early stages:

• the location of the embryo;
• the umbilical cord of the fetus;
• to fix the presence of the rudiments of the upper and lower extremities;
• determine the presence of the makings of the auricles;
• determine the condition of the woman's uterus.

After 10-11 weeks, the fetus reaches the size necessary for a more detailed diagnosis of intrauterine development. This stage of the formation of the internal organs and systems of the embryo allows specialists to detect certain malformations in development. Some of these pathologies may even be incompatible with life, therefore, avoiding ultrasound at this time would be quite imprudent.

The main goals that ultrasound of the first trimester sets for itself:

• determination of the number of fetuses in the uterus;
• detection of the placenta attachment;
• detection of abnormal conditions of the fetus;
• definition of non-developing pregnancy;
• identification of the threat of spontaneous miscarriage;
• establishing an ectopic pregnancy;
• detection of pathologies in the reproductive organs of a pregnant woman;
• assess the quantity and quality of amniotic fluid;
• determine the occurrence of tumors and cysts.

Diagnosis of a number of diseases during the first ultrasound screening gives doctors the opportunity to provide timely assistance to the expectant mother and child in order to avoid complications during pregnancy.

What do specialists first of all pay attention to when they do an ultrasound - screening of the 1st trimester?

First, the doctor will measure the coccyx-parietal size of the fetus (CTE). This indicator refers to the size of the fetus from the coccyx to the crown of the head, not taking into account the length of the legs. The value of the CTE should correspond to the gestational age. A situation in which the fetus is larger than the norm indicates that the baby is developing rapidly and, most likely, the expectant mother will have to bear and give birth to a large child.

The small size of the CTE may indicate either an incorrectly set deadline, or the following deviations in development:

• genetic abnormalities in the fetus;
• developmental delay due to hormonal deficiency, infections or other diseases of the pregnant woman;

If the doctor fails to listen to the heartbeats of the embryo, then intrauterine death of the fetus is ascertained. Usually it is accompanied by the loss of symptoms of toxicosis. As a result, some expectant mothers worry and wonder why they don’t have toxicosis in the first trimester? However, the absence of nausea and a cheerful state of health at the beginning of pregnancy is a phenomenon, although infrequent, but absolutely normal. The first ultrasound will help such women calm down and understand that everything is in order with the baby.

On ultrasound, the doctor will definitely evaluate the size of the collar space of the fetus. The thickness of the collar space (NTP) during normal development of the embryo should not exceed 3 mm. Too much accumulation of fluid in this zone leads to an increase in TP and may be evidence of the presence of chromosomal abnormalities in the fetus, primarily Down syndrome. It is necessary to measure TVP precisely in the period from 10 to 14 weeks, since then it will be ineffective to study this marker of chromosomal abnormalities. As a rule, doctors are guided by the following norms for the size of TVP, which differ in terms of gestational age:

It should be remembered that the development of each child is an individual process and the deviation of the thickness of the collar zone from the norm is not yet a sentence and does not give grounds to establish any final diagnosis.

Another important indicator for ultrasound is the biparietal size (BDP) of the fetal head. It is measured from temple to temple. This value also changes upwards with each new week of pregnancy. Too large BDP can be due to the following reasons:

• a woman is carrying a large fetus (other sizes will also be above the norm);
• spasmodic growth of the embryo (in a couple of weeks the parameters will even out);
• the fetus has a brain tumor or cerebral hernia (these deviations are incompatible with life);
• hydrocephalus (dropsy) of the brain, which was the result of an infection suffered by the mother (with successful antibiotic treatment, pregnancy can be saved).

Small BDP may indicate underdevelopment of the brain.

On ultrasound of the first trimester, the specialist also notes the presence or absence of the nasal bone in the fetus. The absence of this indicator should alert the doctor, since it is in the presence of chromosomal abnormalities that fetal ossification occurs later.

Ultrasound examination enables obstetrician-gynecologists to identify a risk group among women who are expecting a baby. First of all, this applies to those whose fetal parameters and ultrasound norms do not match. Pregnant women at risk are referred for more thorough examinations to confirm or exclude the possibility of having a child with a hereditary pathology.

Ultrasound - screening at week 12 (as, indeed, during the entire first trimester) rarely allows you to accurately determine the sex of the child. In some medical centers, future parents are offered to record a memorable video with the baby.

Biochemical screening

The second important step that is included in genetic screening during pregnancy is the hormonal (biochemical) assessment. To pass this diagnosis of a pregnant woman, it is enough just to donate blood from a vein. This must be done in the coming days after the ultrasound procedure. Special preparation for the analysis is not needed, but it is advisable to exclude fatty foods from the diet a day before blood sampling, do not smoke 30 minutes before the study and exclude physical and mental overstrain. Pregnant women often ask the question - is it possible to eat before screening? It is best to refrain from eating before blood sampling, as even a light breakfast can distort the results of the analysis.

A general blood test in the first trimester is prescribed for absolutely all pregnant women. What does this analysis show? Firstly, it allows you to identify the presence of diseases, including sexually transmitted ones, which can cause severe fetal pathologies: rubella, viral hepatitis B, chlamydia, etc. The following indicators are also mandatory to be studied:

• Blood glucose level

  This parameter helps to prevent and timely notice the onset of gestational diabetes. Timely prescribed treatment and diet will help to avoid complications during pregnancy and the occurrence of pathologies in the fetus.

• Blood protein level

An increased level of protein in the blood may indicate pathologies of the urinary system and kidneys of the mother, and possibly the development of preeclampsia.

As part of prenatal screening, the concentration of certain hormones, the level of which increases in a woman during pregnancy, is assessed. In the first trimester, the following indicators are evaluated during screening: free b-hCG and plasma protein-A (PAPP-A). What it is?

Human chorionic gonadotropin (hCG) is a hormone that is produced by the placenta during pregnancy and is one of the most important indicators of a favorable pregnancy. Each week of pregnancy corresponds to its own norm of the concentration of hCG in the mother's blood:

If the pregnancy is not multiple, then an increased level of hCG may indicate the following:

• there is a high probability that the fetus has Down syndrome;
• may have a hydatidiform mole or choriocarcinoma (a rare malignancy).

A reduced concentration of b-hCG in the first trimester may indicate the following dangerous conditions:

• Edwards syndrome or Patau syndrome in the fetus;
• ectopic pregnancy;
• placental insufficiency
• the threat of spontaneous abortion;

PAPP-A (pregnancy-associated protein A). This protein is produced by the fetal trophoblast, and its concentration in maternal blood in the early stages increases every week of pregnancy. Clinical studies have long confirmed that PAPP-A levels are an excellent marker for detecting a high risk of chromosomal abnormalities in the fetus, which helps to detect severe diseases already in the early stages of pregnancy. Each week of pregnancy corresponds to its normal level of PAPP-A:

The most dangerous condition is precisely the decrease in PAPP-A relative to the norm. This may indicate the presence of the following deviations:

• the development of one of the chromosomal abnormalities: Down syndrome, Edwards syndrome or Cornelia de Lange syndrome;
• spontaneous miscarriage or intrauterine fetal death.

What does an elevated PAPP-A level show? In general, with normal other indicators, such a deviation should not cause much concern. Pregnant women with elevated PAPP-A levels have not been shown to have a higher risk of fetal malformations and complications during pregnancy than women with normal PAPP-A levels. An increase in the concentration of this hormone can be justified by the following reasons:

• a woman bears several fetuses (twins / triplets);
• the fetus is large, and the mass of the placenta is increased;
• low placenta.

After the 14th week of pregnancy, it is not worth taking an analysis for PAPP-A, as it will be considered non-informative.

When screening for the first trimester, experts consider both indicators (b-hCG and PAPP-A) in combination. In the case when PAPP-A is reduced and b-hCG is simultaneously elevated, the doctor is likely to suspect the presence of Down syndrome in the fetus. A decrease in both markers may indicate the presence of Edwards syndrome or Patau syndrome.

There is a possibility that a blood test may give false values. Reasons for skewed results may include:

• obesity, due to which hormonal levels become unstable;
• fertilization with IVF. PAPP-A will be lower by 10-15%, hCG is increased, and ultrasound will show an increase in the fronto-occipital size of the fetus.
• multiple pregnancy.
• stressful condition of a woman.
• diabetes.

After undergoing an ultrasound procedure and donating blood for biochemical markers, the risk of chromosomal abnormalities in the fetus will be calculated for the expectant mother. The results of the screening of the 1st trimester (ultrasound, the level of biochemical markers in the blood) and the mother's personal data will be entered into a special program. The following is indicated as personal data:

• the age of the pregnant woman;
• date of blood sampling, date of ultrasound and gestational age;
• the number of fruits;
• the mother has type 1 diabetes).
• body weight of the female patient;
• ethnicity of the patient;
• does the woman smoke during pregnancy;
• pregnancy occurred naturally or through the use of assisted reproductive technologies (IVF).

After processing the data, the program gives the risk of gene anomalies in numerical form, for example, 1:1900. This would mean that for every 1900 women with the same screening characteristics, there may be one case of the birth of a sick child. A 1:100 screening result in Russia would be considered a high risk threshold. The complex of all screening studies makes it possible to detect Down syndrome with a certainty of 85%.

Identified high risk of Down syndrome on the first screening is not such a rare occurrence. However, it should be understood that deciphering the results of screening is not a final diagnosis and not a sentence, but only an estimated risk of pathology! If it happens that the screening of the 1st trimester shows disappointing results, then the woman will need to seek professional advice from a geneticist, who will most likely prescribe a more thorough examination for the pregnant woman. It consists, as a rule, in the use of invasive diagnostic methods: chorionic villus biopsy (at 10-13 weeks of gestation) or amniocentesis (16-17 weeks of gestation).

Both of these procedures involve surgery and are performed in a hospital. Under the supervision of an ultrasound machine, a specialist punctures the anterior abdominal wall of the mother and collects material containing fetal DNA. In the case of chorionbiopsy, these are pieces of placental tissue, with amniocentesis - amniotic fluid (amniotic fluid). The study of the obtained biomaterials makes it possible to establish with high accuracy (about 99%) the presence or absence of chromosomal abnormalities and congenital diseases in the fetus.

However, these methods have their own significant drawbacks - they are quite unpleasant and stressful for a woman. In addition, there is a risk of spontaneous miscarriage (in about 1.5% of cases) provoked by these procedures. Occasionally, invasive diagnostics lead to a complication of the course of pregnancy, which is expressed in the leakage of amniotic fluid, bleeding, trauma to the fetus, etc.

Modern medicine also offers alternative, safe methods of high-precision prenatal diagnosis. One of these methods is a non-invasive prenatal DNA test based on modern molecular technologies. The test has long been successfully used in medical centers abroad and is becoming increasingly popular among Russian doctors. The test process is as follows:

• a pregnant woman donates blood from a vein;
• fetal DNA is isolated from the obtained material using the sequencing method;
• the genetic material of the fetus is analyzed for the presence of chromosomal pathologies and some hereditary diseases;
• future parents are provided with a detailed transcript of the results of the analysis.

This non-invasive technique has an accuracy of over 99%, which is significantly higher than the accuracy of the combined analysis of screening tests (ultrasound and biochemical blood test). As a result, some modern mothers prefer this test to traditional screening, although it is somewhat more expensive. The advantage of the method is that already at the ninth week of pregnancy it allows to detect a wide range of gene anomalies and hereditary diseases in the fetus. For many expectant mothers, this test allowed them to avoid unsafe invasive diagnostics, and simply helped to gain confidence in the health of their unborn child. In addition, thanks to this method, you can find out the sex of the fetus.

Favorable results of a non-invasive DNA test give an almost 100% guarantee that the fetus does not have the chromosomal abnormalities for which its DNA was tested. If the result indicates a high risk, the woman will still have to undergo an invasive examination, since only the conclusion of an invasive diagnosis can be the basis for an abortion for medical reasons.

In cases of poor results from invasive tests, doctors are likely to recommend that the woman have an abortion for medical reasons. In some cases, such a measure will indeed be justified and reasonable action. However, no one has the right to force a pregnant woman to take such actions; in any case, the decision must be made by the woman herself and her family. It should be understood that any decision in this case must be balanced and well thought out. Many underestimate all the hardships and trials that will have to endure, agreeing to give birth to a baby with severe defects.

Where to do 1st trimester screening?

questions about screening that concern expectant mothers: how is screening done at 12 weeks, where to do screening for the 1st trimester in Moscow, how much does the first ultrasound cost, what is the price in Moscow for biochemical screening, etc. etc.

Naturally, the price for screening of the 1st trimester will differ significantly depending on the city in which the expectant mother lives and how prestigious the medical center she chooses for this examination. It is advisable to contact institutions that specialize in genetic research.

Is 1st trimester screening worth it?

Alas, even the most healthy parents are not immune from the birth of a child with severe defects. The well-known Down syndrome, for example, can occur due to an accidental error during the division of maternal or paternal cells. It is not possible to influence it during pregnancy, since the mechanism for the development of an anomaly starts already at the moment of conception. Many people are also carriers of genetic abnormalities, completely unaware of it. This is revealed only when a sick child is born in the family. Based on at least these two factors, a pregnant woman should not avoid first trimester screening.

Of course, it is worth knowing that many patients are dissatisfied with the quality of screening calculations. Often, in cases of established high screening risk, healthy babies were born, and poor screening results forced the woman (if she refused invasive diagnostics) to be stressed during pregnancy.

There are quite a lot of families that are ready to accept and raise a child, even with severe disabilities. In this case, you can refuse to undergo screening, but first you should soberly weigh your moral and material capabilities, as well as find out as much information as possible about congenital malformations and genetic abnormalities.

If a married couple realizes that it is extremely important for them that the baby is healthy and can lead a full life, then 1st trimester screening should be included in the list of prenatal examinations for a woman. The identified high risk of pathologies will be a reason for more careful monitoring by a gynecologist and a geneticist, and a low risk will allow you to enjoy pregnancy without unnecessary worries.

Screening of the 1st trimester, what is it and when should it be carried out? Is it mandatory and how accurately are the results interpreted? This examination is a combination of two - ultrasound and blood tests, which must take place on the same day.

Prenatal screening in the 1st trimester is considered reliable if 2 conditions are met.
1. It was performed by an experienced specialist in terms of 11 to 13.6 weeks. In this case, the CTE of the fetus should not be less than 45 mm, otherwise the measurement of TVP (collar space) cannot be considered reliable for calculating the risk of having a child with chromosomal pathologies.

2. Risks should be considered, not relying only on ultrasound data, and not looking only at biochemical screening of the 1st trimester. This work must be performed by a special program. And it will give a result on the risks for various genetic and chromosomal diseases. The risks will be registered as average (where only age is taken into account) and individual. So the screening of the 1st trimester is bad if the individual risks are higher than the base (age). In this case, the doctor may refer you for a consultation with a geneticist. And already he, perhaps, will prescribe as soon as possible to repeat ultrasound, only an expert class and (or) invasive diagnostics (cordocentesis, chorionic villus biopsy or amniocentesis). Recommendations will largely be based on ultrasound data. Sometimes at this time, the doctor of ultrasound diagnostics sees very severe malformations in the fetus that are incompatible with life. In this case, a second ultrasound is prescribed and interruption is recommended. Invasive diagnosis is usually not necessary.

If the ultrasound screening of the 1st trimester is generally normal, but the individual risk of having a sick child is high, then the doctor may recommend waiting for the second screening or conducting an invasive diagnosis, the result of which will tell you exactly whether the child is genetically healthy.

In the early stages, a chorionic villus biopsy is performed - this is a rather risky procedure, in terms of a high risk of miscarriage after it. For genetic analysis, the doctor takes cells from the placenta, this procedure is also called a placental biopsy.

After 16 weeks, amniocentesis is done. Amniotic fluid is taken for analysis. This analysis is considered very informative and safer than chorionic villus biopsy and cordocentesis. Women usually agree to the first one in order to avoid prolonged bearing of a non-viable fetus. After all, after 12-13 weeks, you need to wait for the period when doctors can induce artificial labor. And that's about 18 weeks.

But if you didn’t fall into the norms of screening for the 1st trimester by ultrasound, and you don’t want to wait for the second screening, and even more so for invasive diagnostics, there is an opportunity to do a non-invasive test. While in Russia it is not widespread. And very expensive. An analysis costs about 30,000 rubles. But its reliability is about the same as amniocentesis. There is no risk of spontaneous abortion.

1st trimester screening involves looking at the levels of two hormones in the blood of the expectant mother - hCG and PAPP-A. High hCG may indicate a high risk of Down syndrome in a child, and low hCG may indicate Edwards syndrome. At the same time, PAPP-A is also low. But the final interpretation of the results of screening of the 1st trimester is performed only together with ultrasound.

The result of blood tests can be affected by a situation where a woman has a clear threat of miscarriage if she takes progesterone preparations. But with the threat flow very many pregnancies. In addition, a woman carries one or several fetuses, whether she has excess or underweight, whether the conception was natural or in vitro fertilization. Therefore, it is completely wrong to try to interpret and worry about separate blood tests.

When it is better to do screening of the first trimester - the gynecologist can and should calculate directly. That is why it is important to register for pregnancy before 12 weeks. It is advisable to come to the doctor for the first time no later than 8-9 weeks, since there is a shortage of coupons for free screening in many Russian regions. You may need to wait a bit to get a coupon. You just have to wait for this extra time.

But the timing of the screening of the 1st trimester has been determined. It remains only to donate blood and do an ultrasound on the specified day. Many women believe that for greater reliability of the result, some measures need to be taken. Should there be preparation for the first screening during pregnancy and what kind? As such, no preparation is needed. Some experts recommend following a diet a few days before the examination, but this is not very necessary. There is no need for a future mother to limit herself in nutrition. And one more important question - how is the first trimester screening done on an empty stomach or not, what is the best way? In general, it is advisable to take all blood tests on an empty stomach. Including this one. But sometimes it happens that the analysis is scheduled for the second half of the day. Then, of course, you should not starve from the evening of the previous day.

An ultrasound is performed. And sometimes the doctor needs not only abdominal access, but also vaginal. Indicators that are of particular interest to the doctor are the thickness of the collar space, the visualization and size of the nasal bone, and the speed of venous blood flow. In addition, the doctor looks at all the organs and systems of the fetus, the size of the limbs, the head. Measures the cervix of a woman in order to diagnose isthmic-cervical insufficiency at an early stage, if any.

The results of the 1st trimester biochemical screening are usually ready within a few days. And all this time, the expectant mother is in suspense. Especially if you read or personally know the bad stories associated with this survey. Usually a woman visits a doctor once every 2-3 weeks, and if a high-risk screening result arrives before she is due to attend an antenatal clinic, the doctor or midwife calls her and invites her to come. If there is a good screening of the first trimester, you don’t have to worry and additionally don’t take anything and don’t visit genetics. It should be noted that young women have a much lower risk of chromosomal abnormalities.

Prenatal screening examination of the first trimester consists of two procedures: ultrasound diagnostics and a blood test for the possibility of genetic pathologies of the fetus. There is nothing wrong with these events. The data obtained through the ultrasound procedure and blood tests are compared with the norm for this period, which allows you to confirm the good or bad condition of the fetus and determine the quality of the gestation process.

For the expectant mother, the main task is to maintain a good psycho-emotional and physical condition. It is also important to follow the instructions of the obstetrician-gynecologist leading the pregnancy.

Standards for ultrasound diagnostics I screening

In the process of conducting the first prenatal screening in the 1st trimester, the ultrasound diagnostician pays special attention to the anatomical structures of the fetus, specifies the gestation (gestation) period based on fetometric indicators, comparing with the norm. The most carefully evaluated criterion is the thickness of the collar space (TVP), since. this is one of the main diagnostically significant parameters, which makes it possible to identify genetic diseases of the fetus during the first ultrasound procedure. With chromosomal abnormalities, the collar space is usually expanded. Weekly TVP norms are shown in the table:

When conducting ultrasound screening of the first trimester, the doctor pays special attention to the structure of the facial structures of the fetal skull, the presence and parameters of the nasal bone. At 10 weeks, it is already quite clearly defined. At 12 weeks - its size in 98% of healthy fetuses is from 2 to 3 mm. The baby's maxillary bone size is evaluated and compared with the norm, because a noticeable decrease in jaw parameters in relation to the norm indicates trisomy.

On ultrasound 1 screening, the fetal heart rate (heart rate) is recorded and also compared with the norm. The indicator depends on the gestational age. Weekly heart rate rates are shown in the table:

The main fetometric indicators at this stage during the ultrasound procedure are the coccyx-parietal (KTR) and biparietal (BPR) sizes. Their norms are given in the table:

The first screening involves an ultrasound assessment of blood flow in the venous (Arancius) duct, since in 80% of cases of its violation, a child is diagnosed with Down syndrome. And only 5% of genetically normal fetuses show such changes.

Starting from the 11th week, it becomes possible to visually recognize the bladder during ultrasound. At the 12th week, during the first ultrasound screening, its volume is assessed, since an increase in the size of the bladder is another evidence of the threat of developing trisomy (Down) syndrome.

It is best to donate blood for biochemistry on the same day that ultrasound screening is performed. Although this is not a requirement. Blood sampling is carried out on an empty stomach. The analysis of biochemical parameters, which is carried out in the first trimester, is aimed at identifying the degree of threat of genetic diseases in the fetus. For this, the following hormones and proteins are determined:

• pregnancy-associated plasma protein-A (PAPP-A);
• free hCG (component beta).

These figures depend on the week of pregnancy. The range of possible values ​​is quite wide and correlates with the ethnic content of the region. In relation to the average-normal value for this region, the level of indicators fluctuates within the following limits: 0.5-2.2 MoM. When calculating the threat and deciphering the data, not just the average value is taken for analysis, all possible amendments to the anamnestic data of the expectant mother are taken into account. Such an adjusted MoM allows you to more fully determine the threat of developing a genetic pathology of the fetus.

HCG: assessment of risk values

In terms of information content, free hCG (beta component) is superior to total hCG as a marker of the risk of a genetic abnormality of the fetus. The norms of beta-hCG with a favorable course of gestation are shown in the table:

This biochemical indicator is one of the most informative. This applies to both the detection of genetic pathology and the marking of the course of the gestation process and the changes taking place in the body of a pregnant woman.

Pregnancy-Associated Plasma Protein-A Guidelines

This is a specific protein that the placenta produces throughout the entire gestational period. Its growth corresponds to the period of development of pregnancy, has its own standards for each period. If there is a decrease in the level of PAPP-A in relation to the norm, this is a reason to suspect the threat of developing a chromosomal abnormality in the fetus (Down and Edwards disease). The norms of PAPP-A indicators for normal gestation are indicated in the table:

However, the level of pregnancy-associated protein loses its information content after the 14th week (as a marker for the development of Down's disease), since after this period its level in the blood of a pregnant woman carrying a fetus with a chromosomal abnormality corresponds to a normal indicator - as in the blood of a woman who has healthy pregnancy.

Description of 1st trimester screening results

To evaluate the results of I screening, each laboratory uses a specialized computer product - certified programs that are configured for each laboratory separately. They produce a basic and individual calculation of threat indicators for the birth of a baby with a chromosomal abnormality. Based on this information, it becomes clear that it is better to take all tests in one laboratory.

The most reliable prognostic data are obtained during the first prenatal screening in the first trimester in full (biochemistry and ultrasound). When deciphering the data, both indicators of biochemical analysis are considered in combination:

low values ​​of protein-A (PAPP-A) and increased beta-hCG - the threat of developing Down's disease in a child;
low levels of protein-A and low beta-hCG - the threat of Edwards disease in a baby.
There is a fairly accurate procedure to confirm a genetic abnormality. However, this is an invasive test that can be dangerous for both the mother and the baby. To clarify the need to use this technique, the data of ultrasound diagnostics are analyzed. If there are echo signs of a genetic anomaly on an ultrasound scan, an invasive diagnosis is recommended for a woman. In the absence of ultrasound data indicating the presence of chromosomal pathology, the expectant mother is recommended to repeat biochemistry (if the period has not reached 14 weeks), or wait for the indications of the 2nd screening study in the next trimester.

Risk assessment

The information received is processed by a program specially created to solve this problem, which calculates the risks and gives a fairly accurate forecast regarding the threat of developing fetal chromosomal abnormalities (low, threshold, high). It is important to remember that the resulting transcript of the results is only a forecast, and not the final verdict.

In each country, the quantitative expressions of the levels vary. We consider a high level to be less than 1:100. This ratio means that for every 100 births (with similar test results), 1 child is born with a genetic pathology. This degree of threat is considered an absolute indication for invasive diagnostics. In our country, the threshold level is the threat of the birth of a baby with malformations in the range from 1:350 to 1:100.

Threat threshold means that a child can be born sick with a risk of 1:350 to 1:100. At a threshold level of threat, a woman is sent to an appointment with a geneticist, who gives a comprehensive assessment of the data obtained. The doctor, having studied the parameters and anamnesis of the pregnant woman, defines her as a risk group (with a high degree or a low one). Most often, the doctor recommends waiting until the screening study of the second trimester, and then, having received a new calculation of threats, come back to the appointment to clarify the need for invasive procedures.

The information described above should not scare expectant mothers, nor should you refuse to undergo first trimester screening. Since most pregnant women have a low risk of carrying a sick baby, they do not need additional invasive diagnostics. Even if the examination showed a poor condition of the fetus, it is better to find out about it in a timely manner and take appropriate measures.

If adverse results are obtained, what should be done?

If it so happened that the analysis of the indicators of the screening examination of the first trimester revealed a high degree of threat of the birth of a child with a genetic anomaly, first of all, you need to pull yourself together, since emotions negatively affect the bearing of the fetus. Then start planning your next steps.

First of all, it is hardly worth spending the time and money to get re-screened in another lab. If the risk analysis shows a ratio of 1:100, you can not hesitate. You should immediately contact a geneticist for advice. The less time wasted, the better. With such indicators, most likely, a traumatic method of confirming the data will be prescribed. At 13 weeks, this will be an analysis of the chorionic villus biopsy. After 13 weeks, it may be recommended to perform cordo- or amniocentesis. Analysis of the chorionic villus biopsy yields the most accurate results. The waiting time for results is about 3 weeks.

If the development of fetal chromosomal abnormalities is confirmed, the woman will be recommended artificial termination of pregnancy. The decision is definitely up to her. But if a decision is made to terminate the pregnancy, then the procedure is best done at 14-16 weeks.

- a mass examination of women, which is done at a period of 11-13 weeks of pregnancy. The first screening allows you to identify congenital anomalies in the development of the fetus, as well as the risk of its birth with severe genetic disorders.

Screening in the first trimester includes an ultrasound examination and a biochemical blood test for specific indicators (β-hCG and PAPP-A). Screening is subject to all pregnant women without exception. At the same time, a woman has the right to refuse such an examination. But, it should be remembered that failure to screening can lead to adverse pregnancy outcomes.

When is screening mandatory?

There are risk groups for pregnant women who must undergo prenatal diagnosis without fail.

The first screening is carried out in such cases:

• All women over the age of 35.
• If in the past there were miscarriages or non-developing (frozen) pregnancies.
• In the presence of harmful professional factors.
• Risk of miscarriage.
• If the family already has a child with congenital pathologies or chromosomal disorders. Or such abnormalities were diagnosed in previous pregnancies.
• Women who have had infectious diseases in the first trimester.
• Women who suffer from alcoholism, smoking or drug addiction.
• If there are hereditary diseases in the family of one of the parents.
• The presence of a family relationship between the parents of the unborn child.
• Women who have taken pharmaceuticals that are contraindicated for use during gestation.

Procedure for the first screening

To pass a reliable first screening, the 1st trimester has certain limits for this. The first prenatal diagnosis is carried out from the 10th week of pregnancy until the 14th week. The most reliable indicators will be those obtained at 11-12 weeks. It is very important that the deadline is set correctly. This will be done by a gynecologist and will determine when it is better to undergo the first screening.

In order to undergo a perinatal examination, it is necessary to properly prepare for examinations. If ultrasound is performed with a vaginal probe, then special preparation is not required. If ultrasound is done through the abdomen, the following rules must be observed:

• The bladder must be full.
• Do not urinate 4 hours before the ultrasound.

If a non-developing pregnancy is detected on ultrasound, the examination is terminated.

For a biochemical blood test, the preparation should be as follows:

• Before you donate blood, you must definitely do an ultrasound of the fetus. This is the most important condition, since the indicators in the biochemical blood test directly depend on the gestational age.
• It is necessary to take a blood test from a vein strictly on an empty stomach. If necessary, you can take food with you and eat after taking a blood test.
• A couple of days before the biochemical examination, all potential allergens should be excluded from the diet. They can be seafood, nuts of any kind, chocolate. Also, do not eat spicy, fatty and smoked foods.

If the basic rules are not followed, the results of the first screening may be incorrect.

What pathologies can be detected at the first screening?

Screening of the 1st trimester reveals gross developmental disorders of the child and chromosomal pathologies. When screening, the following abnormalities can be detected or suspected:

• Down syndrome is the most common genetic anomaly.
• Lange syndrome. It is characterized by multiple malformations. If the baby survives, then he has a profound mental retardation.
• Patau syndrome. It is characterized by severe damage to the organs of the child. Such children die in the first months after birth.
• Edwards Syndrome. An ultrasound revealed an anomaly in the development of the umbilical vessels - 1 artery and 1 vein. Normally, the umbilical cord contains 3 vessels - 2 arteries and 1 vein.
• Malformations of the neural tube in the fetus.
• Omphalocele is a hernial protrusion in the region of the umbilical ring, which includes internal organs.
• Anencephaly is the absence of the brain.

All transcripts according to the results obtained are done by a gynecologist.

Deciphering the results of ultrasound during the first screening

At the first screening during ultrasound, the following indicators are evaluated:

• The distance from the crown to the coccyx (KTR), which normally ranges from 33 to 73 mm, depending on the gestational age. Below is a table that shows the KTR standards:

• fetal TVP (collar space thickness).

Normal TVP is from 1.5 to 2.7 mm. During screening, TVP is a very important marker of genetic disorders. The table below shows the norms of TVP:

If the result of TVP is more than 3 mm, then this can be regarded as a sign of Edwards or Down syndrome.

• The size of the nose bone.

This is a marker by which Down syndrome can be suspected. Determination of the nasal bone is necessarily included in the screening of the first trimester. According to ultrasound, the nasal bone is normally determined from 10 to 11 weeks. Bone size is assessed from 12 weeks. Normally, the nasal bone should be more than 3 mm. The absence of the nasal bone and an increase in TVP are a clear sign of Down syndrome.

• Biparietal size (BDP).

With ultrasound, this size is determined as the distance between the parietal tubercles. By the end of the first trimester, the result of BDP is normally more than 20 mm.

• Fetal heart rate.

The heart rate also differs depending on when screening is done in the first trimester. Normal heart rate is 150 to 180 beats per minute.

• The development of the internal organs of the fetus, umbilical vessels, placenta is assessed.

Deciphering the results of a biochemical blood test

After a successful ultrasound, it is necessary to take a blood test for the content of specific substances: β-hCG and PAPP-A. In addition, the MoM coefficient is calculated.

• Free β-hCG is a specific fetal hormone. Screening of the 1st trimester allows you to determine its maximum values. Determination of the level of β-hCG allows the most reliable calculation of the risk of Down's disease. Below is a table that shows the normal values ​​​​of the level of β-hCG:

It is important to remember that in different laboratories, the normal values ​​​​of the level of β-hCG may differ.

• PAPP-A is a protein substance produced by the placenta. During the period of gestation, the level of a specific protein is constantly growing. Deviations from the normal values ​​presented in the table may indicate the presence of deviations in the child.

Do not forget that the PAPP-A values ​​\u200b\u200bin each laboratory are also different.

• The MoM coefficient is calculated when determining β-hCG and PAPP-A. Can be used instead of standard units. His performance normally ranges from 0.5 to 2 from 9 to 13 weeks. If MoM is below 0.5, then this may indicate a risk for Edwards syndrome in a child. When MoM exceeds 2, this indicates a possible Down syndrome.

Calculation of perinatal risk

In order for the screening of the first trimester to be as reliable as possible, it is necessary to take tests and undergo ultrasound in the same institution. The risk of deviations is calculated based on the results of β-hCG, PAPP-A, the age of the pregnant woman, individual characteristics of the body, harmful factors, and comorbidities. The data obtained is entered into a computer, into a special program that calculates the risks. The program gives the final result in the form of a fraction. For example, the program issued a risk of 1:400. The decoding will be as follows: out of 400 pregnancies with the entered indicators, 1 baby with a pathology will be born. Depending on the value obtained, the conclusions can be as follows:

• Positive test. It means that during this pregnancy there is a high risk of having a child with a pathology. In this case, a genetic consultation is carried out. The issue of an additional examination to establish or refute the diagnosis is being decided. In this case, an amniocentesis or a biopsy of the chorionic villi is done.
• Negative test. This means that the risk of pathologies is low and there is no need to conduct an additional examination. In this case, the pregnant woman undergoes routine screening in the 2nd trimester.

First trimester and screening for Down syndrome

Down syndrome in the fetus can be assumed as early as 10-11 weeks. When conducting an ultrasound, the following characteristic signs of this syndrome are revealed:

• TVP thickening more than 3 mm. Deviation of TVP from the norm can also indicate other genetic disorders.
• No nasal bone in 70% of cases. It is important to know that in healthy children in the early stages, the nasal bone may not be determined.
• Violation of blood flow through the ductus arteriosus.
• Hypoplasia (reduction) in the size of the upper jaw.
• Bladder enlargement.
• Raised fetal heart rate.
• Pathology of the vessels of the umbilical cord: one artery and one vein.

Screening of the first trimester is an important stage of examination during gestation. With its help, it is possible to exclude or identify severe pathologies in a child, often incompatible with his life. In order for the indicators to be reliable, it is necessary to follow the recommendations of the doctor and undergo screening on time.

If the screening results reveal a high risk of pathologies, do not panic. It is necessary to contact a specialist who will prescribe an additional examination. It is important to remember that high risk is not a diagnosis, but only an assumption, which is often refuted after additional examinations.