Genetic analysis during pregnancy plays an important role. It helps to determine intrauterine anomalies of the fetus, to calculate diseases of hereditary etiology. Some deviations due to genetics can be determined at the stage of routine screening. If there is a probability of chromosomal abnormalities, highly informative diagnostics, consisting of invasive methods, is shown. You can get a forecast regarding offspring until the moment of conception. It is necessary to undergo a series of genetic tests even when planning a pregnancy.
It is important to plan for replenishment in the family. At this stage, you may need the help of a narrow-profile specialist - genetics. Why refer to genetics? So you can learn about the risks associated with the health of future offspring, even before the birth of a new life.
Only a specialist can give a forecast regarding the new generation of the family. Conducting genetic tests before the time of pregnancy allows you to determine possible hereditary diseases of the unborn child. This is especially important if cases of genetic diseases have been recorded in the family of the couple. At the planning stage of conception, chromosome sets of partners are informative for genetics. The risk assessment of the birth of a baby with deviations is carried out using a number of specific studies, after which the geneticist makes a prognosis.
If there are no serious reasons for consulting a geneticist, and the couple simply decided to play it safe, then sometimes a clinical and genealogical diagnostic method is enough. It consists in collecting pedigree data with the definition of conditions caused by genetic information. The geneticist analyzes the source data and makes a prediction. When clinical and genealogical diagnostics determines the likelihood of developing pathologies in the offspring, an additional examination of partners is indicated.
Carrying out genetic analyzes even when planning a pregnancy has not yet become commonplace for most families. Therefore, in modern medicine, close attention is paid to prenatal diagnostics of genetic information. There are a number of tests that allow you to learn about chromosomal pathologies in utero.
When is Genetic Analysis Needed?
Children receive hereditary characteristics through transmission from their parents. Gene information is stored on forty-six chromosomes. This is the standard set. However, if a chromosomal disorder occurs, pathology occurs. Modern medicine can determine the likelihood of gene failures during planning and in the prenatal period.
All couples dream of a healthy baby. Genetic studies help to find out about the likelihood of a baby being born with hereditary diseases. A pregnant woman can take tests at will. However, there are a number of indications in which complex tests are a necessity. Do not ignore genetic tests if:
An additional study is indicated if the impact of negative factors on the female body was recorded in the first trimester. For example, when transferring a viral infection in an “interesting” position. Or if the expectant mother, not knowing about the new life inside, took medications, abused alcoholic beverages, underwent an x-ray. The influence of these factors on genes is not fully understood, but they can cause various developmental disorders that can be determined in utero.
Genetic analysis is voluntary. But if there is evidence, you need to listen to the recommendations of the doctor and undergo a comprehensive examination. This will help to identify pathologies in the embryo and make an informed decision to continue or terminate the pregnancy.
Screening diagnostic methods
Screening diagnostics plays an important role in determining genetic pathologies in the embryo. It is done quite early. Simple diagnostic methods allow you to determine a risky pregnancy. To make an accurate diagnosis, genetic analysis during pregnancy should be more informative than screening studies. Which method to choose is individually determined by the doctor.
The well-known screening methods include ultrasound. The first scheduled examination is recommended to take place at about 12 weeks. At this stage, markers of some hereditary diseases can be determined. For example, at the first ultrasound examination, the risks of having Down syndrome in the fetus are determined. Ultrasound is repeated after the 20th week. The second screening is highly accurate compared to the first one.
According to the results of ultrasound, one can only assume a genetic abnormality in the embryo. This method aims to identify risks. The preliminary diagnosis requires confirmation. A woman who is in the risk group according to the results of an ultrasound scan should listen to the doctor's recommendations. With a high probability of the presence of pathology after screening, a number of specific tests are prescribed.
You should not make hasty conclusions and take action, relying only on the results of ultrasound. The decision to terminate a pregnancy for medical reasons should be made only after a comprehensive examination and accurate diagnosis. If there are doubts about the correctness of the diagnosis, you need to consult with several doctors.
triple test
Genetics during pregnancy can be clarified using a triple test. It is especially important to pass the analysis if you belong to a risk group. If the ultrasound pointed to possible abnormalities, then testing can confirm or refute the guess. A triple test is a blood test in which three main indicators are examined:
A violation of the norm of the triple test indicators can indicate both a hereditary pathology and an anomaly that has arisen in utero (not related to chromosomal information). The level of hormones does not accurately determine the genetic disease, but suggests that the fetus has defects. The result of a triple blood test may indicate:
- the presence of an extra chromosome in the embryo (trisomy);
- Edwards syndrome with its characteristic numerous anomalies of organs, developmental delays;
- heart defects;
- renal pathologies;
- intrauterine infections.
If a blood test for hormones showed normative deviations, then the expectant mother will have to undergo an additional examination. Only invasive diagnostic methods can accurately determine the nature of the pathology. Only with their help are determined hereditary diseases in the embryo. Conducting invasive diagnostic procedures, like any invasion of the body of a pregnant woman, is associated with a certain risk. However, this is the only way to get reliable information about the condition of the fetus.
Invasive genetic diagnostics
If the ultrasound determined the deviation and positive results of the triple analysis for genetics came, even during pregnancy, an examination is carried out using invasive techniques. This involves taking "internal material" for chromosomal analysis. Carrying out procedures requires an invasion of the female body.
The diagnostic methods of the invasive type include:
Analyzes that read genetic information can diagnose serious fetal diseases. When hereditary anomalies are identified that can become an obstacle to the normal development and socialization of the baby, parents get the right to decide the fate of pregnancy at any time. For some pathologies identified through genetic studies, prenatal therapy can be performed. It reduces the risk of complications associated with a hereditary disease.
Hidden dangers of invasive procedures
Invasive diagnostic methods involve certain risks. Any intervention in the body of the expectant mother is undesirable. An ultrasound and a triple test determine a risky pregnancy. They do not allow an accurate diagnosis. Only invasive diagnostics can reveal a hereditary anomaly in a fetus. After confirming the diagnosis, the family will be able to gather more information about the pathology and make an informed decision regarding pregnancy. Parents who are not ready to terminate a pregnancy under any circumstances also need time to get used to the idea of having an unhealthy baby.
Invasive prenatal diagnosis is not widely used. Due to the high risk of complications, procedures are performed according to special indications. The risks of analyzes requiring invasive material sampling include:
- infection of the embryo or future mother;
- detachment of the placenta;
- miscarriage;
- outpouring of amniotic fluid.
Future parents should be aware of the risks of performing specific diagnostic procedures. However, if a genetic disease is suspected during the initial screening, then an accurate diagnosis can only be made with the help of additional tests. To minimize the risks of possible complications after invasive procedures, you need to choose the right doctor and laboratory where the tests will be performed.
Genes are carriers of hereditary information that determine character, height, eye and hair color, and other characteristics. Each person has certain genes that are contained in a set of 46 chromosomes. At the moment of conception, the sets of chromosomes of the mother and father merge, while hereditary characteristics are transmitted from parents to the unborn baby. Sometimes some factors can lead to damage to the chromosomes, which leads to various pathologies. This inevitably affects the health, physical and mental development of the unborn child. To exclude pathologies, genetic analysis is provided during pregnancy.
Indications for genetic analysis during pregnancy
An analysis for genetics during pregnancy is strongly recommended in cases where a woman is at risk of having a child with hereditary diseases:
- if in the family of the mother or father there were cases of the birth of children with developmental pathologies, congenital diseases and deformities;
- women over 35 years of age, since late pregnancy increases the risk of genetic mutations leading to diseases;
- if a woman has been drinking alcohol for a long time, had a dependence on drugs and medicines in the past;
- if a woman had an infectious disease during pregnancy;
- if the woman has had a miscarriage in the past or the pregnancy was resolved by stillbirth.
Non-invasive research methods
The first stage of genetic examination is non-invasive or traditional research methods:
- blood chemistry;
- ultrasound procedure.
A genetic blood test during pregnancy is based on the fact that during the bearing of a child, the level of certain proteins in a woman's blood changes. There is a connection between the content of these proteins and various pathological conditions, including Down's syndrome. With the normal development of pregnancy, the level of proteins changes naturally, so it is important to establish the gestational age at which the test is performed.
Ultrasound examination allows you to measure the diameter of the space in the region of the collar zone of the fetus, filled with fluid. There is a relationship between this value and the potential risk of Down syndrome. A large amount of fluid (edema) indicates possible pathologies and defects in the development of the fetus.
Already at the first ultrasound, which is performed at 10-14 weeks of pregnancy, the doctor can see the presence of developmental disorders in the child. At the same time, according to the results of genetic tests during pregnancy, the level of risk is assessed based on the totality of all the main parameters: the diameter of the fluid in the collar zone, the results of the analysis of proteins in the woman's blood and her age.
Early genetic tests during pregnancy can reveal the presence of pathological changes in the body of the fetus, which occur as a result of violations of the integrity of the chromosome set or are inherited.
If, according to the results of genetic studies during pregnancy, a high risk is revealed that the child may have Down syndrome or other pathologies, the woman is offered to undergo a series of additional diagnostic tests using invasive methods.
Invasive methods of genetic analysis during pregnancy
If a genetic blood test during pregnancy and ultrasound revealed suspicions of possible pathologies of the child's development, diagnostics by invasive methods are possible, which allow to determine with high accuracy the presence of about 400 pathologies:
- Amniocentesis is a study of amniotic fluid, which is prescribed at 15-18 weeks of pregnancy. During this analysis, amniotic fluid is taken by puncturing the uterus with a long needle.
- Chorionic biopsy - a study of the cells from which the placenta develops. Material for this analysis is taken through the cervix or by puncture of the abdominal cavity. The disadvantage of the method is the increased likelihood of miscarriage.
- Placentocentesis is a study of placental tissue cells. The analysis is carried out if the pregnant woman has had an infectious disease. This test is done in the second trimester of pregnancy and requires general anesthesia. In this case, a puncture of the anterior abdominal wall is made and a piece of the placenta is taken.
- Cordocentesis is a study of cord blood. For this test, a thin needle is inserted through the anterior abdominal wall into the umbilical cord and a blood sample is taken for genetic analysis during pregnancy. The disadvantage of the method is a rather high failure rate when trying to take blood, in addition, the risk of fetal loss exceeds 2%.
Evaluation of the results of genetic analysis during pregnancy
Genetic studies during pregnancy may indicate the risk of Down syndrome and other pathologies within the following limits:
- High risk - more than 1:200 (0.5%). Upon receipt of such results, the woman will be referred for genetic counseling to consider the possibility of performing diagnostic tests of the chorionic villous or amniotic fluid.
- The average risk level is in the range of 1:201 to 1:3000, with such results, a woman is recommended to conduct additional screening at 16-17 weeks of pregnancy to confirm the risk assessment. On this analysis, a blood test is carried out for the content of alpha-fetoprotein, the hormone E3 (estriol) with or without inhibin. If the resulting risk exceeds 1:380, the woman is referred for genetic counseling to consider amniotic fluid testing.
- Low risk - less than 1:3001 - a satisfactory result, in which there is no need to conduct additional tests for the detection of Down syndrome.
Today, a consultation with a geneticist causes more concern among parents, what if something goes wrong in the development of the future baby. Only 20% of families seek counseling during pregnancy. Some are afraid to hear a terrible verdict, others prefer not to know anything in advance, still others amuse themselves with the fact that genetic diseases are very rare. Of course, the risk of genetic diseases can be reduced to a minimum by visiting a doctor before conception of crumbs. When the fact of pregnancy is already present, the gynecologist prescribes a genetic analysis during pregnancy. At the same time, such a survey is one of the most informative and important.
Why take an analysis
Inheritance is like a lottery. Healthy parents quite often give birth to a seriously ill child. The probability of risk, although very small, is for everyone. The reason is always the same - a mutation in the chromosomes or genes.
Chromosomal mutations are changes in the number of chromosomes in a cell. Errors in the chromosome set are often incompatible with the life of the unborn child. Since from time immemorial nature leaves the strongest, a woman has miscarriages, sometimes repeated, often the birth of a dead child. But sometimes such "mistakes" of genes lead to the birth of a baby with severe pathologies. The most famous worldwide is Down syndrome.
Genetic abnormalities are associated with changes in the structure of DNA molecules. It is impossible to determine with a quick glance that a child was born with a mutated gene. This will definitely manifest itself over time, especially if the baby is not just a carrier of such a hereditary disease.
In total, there are about 3500 such diseases. They account for 2% of all mankind. For example, only 1 in 1200 babies is born with cystic fibrosis. Therefore, it is so important to undergo an examination prescribed by a doctor. Only on the basis of the results of the audit is it possible to make a further decision.
High risk group
An analysis for genetics during pregnancy must be prescribed to women who have a high risk of having a child with a developmental anomaly due to certain circumstances:
- women over 35 and men over 40. The risk of chromosomal and gene mutations increases significantly with age;
- there were already genetic diseases in the family;
- marriage to a close relative;
- one of the children in the family has already been born with a genetic pathology;
- previous pregnancies ended in miscarriages, fetal fading or stillbirth.
- women who abuse alcohol and drugs before and during pregnancy;
- real pregnancy is aggravated by a serious infectious disease;
Methods of genetic control
During pregnancy, prenatal screening, which is carried out twice, allows you to "catch" the risk of genetic pathologies. The fetus and placenta produce specific proteins. If there is a genetic or chromosomal pathology in the body, the level of these proteins changes.
From the 11th to the 13th week of pregnancy, the first screening is carried out. Such a genetic analysis during pregnancy reveals Down and Edwards syndrome - diseases manifested by mental retardation, anomalies in the development of internal organs, and determines gross malformations of the central nervous system. It is carried out in two stages:
- ultrasound. During the examination, the doctor may see a thickened collar zone or not see the nasal bone.
- Genetic blood test during pregnancy. It is taken from a vein and is called a "double test", since the risk of chromosomal abnormalities is determined by two markers: beta - hCG, a protein produced by the membrane of the embryo, and PAPP-A - a blood plasma protein. With increased rates of the first and underestimated data of the second, we can talk about the presence of a genetic pathology on the part of the fetus.
From 15 to 18 weeks, the pregnant woman undergoes a second screening. A blood test determines the presence of gene mutations with three markers - hCG, AFP and estriol. Indicators of a certain concentration of these substances in the blood of a pregnant woman suggests the risk of forming a neural tube defect - a malformation of the spinal canal or brain.
With this type of study, the doctor first of all draws on the AFP indicator - a protein produced by the organs of the gastrointestinal tract and the fetal liver.
The doctor determines the final screening result from a combination of ultrasound and blood tests.
Many expectant mothers, having received the results in their hands, are stressed when they see deviations from the norm. This may be absolutely unrelated to the deformities of the unborn child. So the results are often unreliable if the pregnancy is multiple, the mother is overweight or, conversely, her lack, the presence of diabetes and other chronic diseases. Even an incorrectly calculated gestational age can cause confusion in the results.
Screening preparation
Blood for research is taken from a vein in the morning on an empty stomach or not earlier than 5 hours after the last meal.
Additional expertise
When the doctor has significant reasons for suspicion of genetic pathology, he sends the expectant mother for additional examinations. They will either confirm or refute the earlier diagnosis. But even here it is not worth talking about 90% accuracy.
- Chorionic biopsy. It is carried out for a period from 11 to 13 weeks. A special syringe with a long needle takes a sample from the shell of the fetal egg. The sample is taken through the cervix.
- Amniocentesis. Recommended after 15 weeks. A sample of amniotic fluid is taken under the control of an ultrasound probe.
- Taking a puncture of the umbilical cord of the fetus. A woman is examined in the period from 22 to 25 weeks of pregnancy.
The big disadvantage of such studies is that they can provoke a miscarriage or bleeding, since in order to conduct them, doctors have to invade the fragile union of the placenta and the fetus.
- Diagnosis of pathologies by maternal blood. Fetal DNA is isolated from the blood and examined for chromosomal abnormalities. Such an analysis for genetic diseases in pregnant women can be taken from 6 weeks. The result is ready within two weeks. To date, this is the most accurate and early method of examination.
Deciphering all analyzes is a matter of a specialist. But no one can give you specific recommendations if, after many checks and rechecks, the risk of having a child with irreversible changes in the body is still high. This is a personal and rather difficult decision that must be made by you, your husband, and those close to you. Before accepting it, you will have to weigh a lot and reconsider your whole life. You have no right to make a mistake with your wrong choice.
Genetic tests during pregnancy are a reliable way to assess the risks of chromosomal and other fetal abnormalities in the short term. For this, modern gynecology has several safe and indicative methods of invasive and non-invasive nature.
All pregnant women who are registered at the antenatal clinic on time are necessarily sent for a screening test at the 12th week (end of the first - beginning of the second trimester) for detection in the fetus.
Tests required for delivery:
- Down syndromes;
- congenital pathologies of internal organs;
- Edwards syndrome;
- gross defect of the neural tube;
- physical anomalies of development;
- Patau syndromes;
- Turner and Cornelia de Lange syndromes.
If any deviations are found or suspected, a number of additional tests and studies of an invasive nature are carried out, only they can confirm or refute a particular diagnosis with a high degree of probability.
Who is at risk
Experts identify several main reasons why women during pregnancy may be at risk. Certain categories of girls are most often subject to spontaneous abortion, the development of intrauterine anomalies and chromosomal mutations in the fetus.
Genetic analysis during pregnancy: what is it for?
Women at risk:
- Pregnancy under the age of 15 years. Too young expectant mothers are at risk of developing eclampsia, and they are also extremely likely to have premature births and have a baby with a small birth weight.
- The age of the pregnant woman is over 40 years. This category of women is more likely to have a child with genetic defects, in particular, with Down syndrome.
- Body deficiency in a pregnant woman(weight less than 40 kg), small height (up to 150 cm) can lead to premature birth and the birth of a small child.
- Overweight pregnant woman also has a negative impact. The expectant mother is at risk for developing diabetes, and the child may also be born overweight.
- Pathologies of the reproductive organs a woman can provoke a miscarriage or premature birth.
- Chronic diseases of the pregnant(diseases of internal organs, diabetes mellitus, hypertension, heart failure) during pregnancy have a negative impact on both the woman herself and the child.
- Cases of genetic diseases in the pedigree increase the risk of developing such pathologies in the unborn baby.
- During multiple pregnancy there is a high risk of spontaneous abortion or premature birth.
- Infectious diseases, identified during pregnancy, negatively affect the development of the fetus, cause intrauterine pathologies of the fetus.
- Smoking cigarettes and drinking alcohol during pregnancy can cause intrauterine anomalies in the fetus, weight loss, premature birth.
In these cases, timely genetic analysis allows doctors to detect certain abnormalities in the development of the fetus and choose the best strategy for managing pregnancy.
Methods for conducting analysis for genetics
Genetic tests during pregnancy can be performed using various methods:
- ultrasound examination of the fetus;
- a biochemical blood test to search for markers indicating fetal malformations (“double” and “triple” tests);
- amniocentesis - laboratory analysis of amniotic fluid, performed according to indications at 15-18 weeks;
- placentocentesis - taking the placenta for analysis, is required after the mother has suffered an infectious disease;
- chorion biopsy to determine the genetic abnormalities of the fetus (performed according to indications, also recommended for women after 35 years).
When do
To assess the risks of developing genetic pathologies in the fetus at certain stages of pregnancy, special analyzes and studies are carried out.
Analysis for genetics during pregnancy: a complete list. Required tests:
- 10-13 weeks: the first mandatory screening, including ultrasound of the fetus and a laboratory blood test for the presence of chromosomal abnormalities (“double” test). If some genetic diseases are suspected at this time, a chorionic biopsy can be ordered individually.
- 15-18 weeks: a blood test to determine gene mutations (“triple” test), and according to indications, amniocentesis or placentocentesis can be prescribed.
- 22-25 weeks: scheduled ultrasound examination of the fetus, puncture of the umbilical cord of the fetus in case of suspected genetic abnormalities.
How to prepare
An analysis for genetics during pregnancy does not require specific preparation, it is enough to adhere to standard recommendations:
- blood must be taken in the morning on an empty stomach;
- before an ultrasound, you should not overeat, and with increased gas formation, you should take Espumizan or Smecta.
Non-invasive methods
Non-invasive methods for diagnosing genetic abnormalities in the fetus include:
- ultrasound examination of the fetus for a period of 10-13 weeks (allows you to determine the size of the collar zone of the fetus, make sure that it meets the standards of intrauterine development);
- biochemical blood test (blood sampling is carried out for a period of 12 weeks from a vein, the presence of genetic diseases of the fetus is determined by two markers - beta-hCG and PAPP-A).
Prenatal screening
This study consists of a set of diagnostic measures (ultrasound and blood tests) that allow, at the end of the first and beginning of the second trimester, to determine the likelihood of fetal abnormalities, congenital malformations, and chromosomal abnormalities. The procedure is absolutely safe, it is prescribed and carried out free of charge to all pregnant women, registered with a doctor in a antenatal clinic.
Required screenings:
- The first mandatory screening is carried out at 10-13 weeks, includes a fetal ultrasound and a "double" blood test.
- The second mandatory screening is prescribed at 18-20 weeks, consists of an ultrasound and a "triple" blood test.
ultrasound
Ultrasound is a safe and reliable method that allows you to monitor the development of the fetus and the state of the mother's reproductive system.
For the entire period of observation of a pregnant woman, a planned ultrasound of the fetus is carried out three times at a strictly fixed time.
Scheduled ultrasounds:
- Ultrasound at 10-14 weeks. Aimed at identifying serious disorders of the nervous system and chromosomal abnormalities, for this, the specialist measures the thickness of the collar space and the size of the bone of the nose, as well as fetometry of the fetus (assessment of various physiological parameters).
- Ultrasound at 18-20 weeks. The specialist measures the length of the body, evaluates the structure of the spine and the symmetry of the face, and checks the internal organs of the unborn baby. In addition, the doctor should pay attention to the condition of the mother's reproductive organs and their readiness for further bearing and childbirth.
- Ultrasound at 30-32 weeks. The general condition of the fetus, the spinal cord and brain, the formation of all vital organs and systems are assessed. Special attention is paid to the condition of the uterus and placenta, the amount of amniotic fluid, blood flow is checked.
Biochemical "triple" test
A genetic test during pregnancy includes a "triple" test, which is prescribed in the second trimester (16-18 weeks).
Blood is taken from a vein and analyzed for the following markers:
- hCG level;
- AFP (protein produced by the liver of the unborn child);
- free estriol level.
The data obtained allow us to assess the risk of having a child with genetic abnormalities, but this information is not an accurate diagnosis.
It only provides information to the doctor to predict possible risks and plan individual pregnancy management.
Invasive techniques
Invasive techniques are not mandatory for all pregnant women, they are prescribed individually if the results of routine screening indicate a high probability of chromosomal abnormalities in the fetus.
Invasive methods for determining the genetic diseases of the fetus in pregnant women include:
- amniocentesis (laboratory study of amniotic fluid);
- chorion biopsy (analysis of chorion cells);
- placentocentesis (examination of the placenta);
- cordocentesis (analysis of cord blood).
Chorionic biopsy
Chorionic biopsy is a modern method of prenatal diagnosis, which is carried out by sampling and examining embryonic tissues (villous outer shell). With the help of the data obtained, it is possible to identify about 3800 diseases with a high degree of certainty, which include chromosomal abnormalities (Patau, Down, Edwards syndromes, etc.).
Indications for a chorionic biopsy are:
- genetic and chromosomal abnormalities of the fetus during previous pregnancies in a woman;
- hereditary diseases in the family;
- identified risks of chromosomal abnormalities based on the results of the first mandatory screening.
The procedure is possible at the end of the first - the beginning of the second trimester (10-14 weeks). Before taking the material, the abdomen is treated with an antiseptic, then a puncture is performed with a special puncture needle.
Passing through the abdominal anterior wall and uterus, the needle is immersed in the chorionic tissue, the cells are taken. During and after the procedure, continuous ultrasound monitoring of the fetus and uterus is performed.
Amniocentesis
Amniocentesis is an analysis of amniotic fluid to determine fetal malformations. Material for research (5-30 ml of liquid) is obtained by puncturing the uterus and amniotic bladder through the abdomen with a special needle. The procedure is carried out under constant ultrasound control.
Amniocentesis allows you to determine:
- chromosomal abnormalities;
- hereditary metabolic diseases;
- anomalies in the development of the nervous tissue and tube;
- fetal hypoxia.
Amniocentesis is safe during the first two trimesters of pregnancy, the period from 16 to 18 weeks is considered the most favorable.
The indications for analysis are:
- cases of genetic hereditary diseases in the family, including in children born earlier;
- identified risks of congenital diseases based on the results of ultrasound screening, as well as the “double” and “triple” tests.
In addition, an individual analysis can be prescribed if a pregnant woman takes drugs that can affect the fetus, as well as after infectious diseases.
Norm and deviations
Genetic tests during pregnancy are aimed at finding certain markers, based on the indicators of which, specialists can judge the existing abnormalities in the fetus.
The “double” test, carried out in the first trimester, determines the possibility of developing Edwards and Down syndromes in the fetus according to two indicators - beta-hCG and PAPP-A.
Main characteristics:
- Beta HCG is a protein produced by the tissues of the shell of the embryo. An elevated level of free β-subunit may indicate a disease such as Down's syndrome.
- The second important component of the test is the level of PAPP-A, (plasma protein A associated with pregnancy). With a lower level of this indicator in the fetus, there is a high probability of having Edwads or Down syndrome, neural tube anomalies, and can also be a symptom of a missed pregnancy.
With a “triple” test, 3 indicators are evaluated (NE (non-conjugated estriol), AFP (alpha-fetoprotein), β-hCG), consisting of a complex relationship.
The results show:
- an increased level of hCG with reduced levels of other components indicates a high probability of Down syndrome in a child;
- a reduced level of hCG with normal AFP and NE may indicate Patau syndrome;
- reduced content of all three indicators - Edwards syndrome;
- elevated AFP can signal severe neural tube defects and intrauterine growth retardation.
Genetic blood control is prognostic in nature, so the final diagnosis is not established by them.
Test Accuracy
Based on average data, the reliability of genetic tests performed during pregnancy is rated quite high:
- "double test" - 68%;
- "double test" in conjunction with fetal ultrasound - 90%;
- "triple test" - 60-70%;
- chorion biopsy - 99%;
- amniocentesis - 99%.
The error in the data of the ultrasound examination of the fetus and the analysis of the mother's blood is due to the prognostic orientation of the methods and the probable discrepancy between the expected and actual dates of conception. In turn, invasive techniques can confirm or refute the alleged diagnosis with great accuracy.
Sore Tests
The description of the process of taking material for genetic analysis may give the impression of a painful procedure, however, modern equipment and methods of pain relief can minimize the possible occurrence of discomfort.
How the tests are done:
- To conduct a "double" test, a standard blood sample is taken from a vein, so it does not cause any particular pain.
- When sampling the chorion for a biopsy, local anesthesia is performed, so the procedure can only cause slight discomfort.
- Amniocentesis is performed under local anesthesia and is therefore considered relatively painless.
Waiting for test results
An analysis of genetics during pregnancy requires a certain amount of time to process and obtain reliable results.
Testing times:
- "Double" and "triple" tests - 14-20 days.
- Chorionic biopsy: the result is possible after 3-4 days, but in some cases it takes more time, because. cells grow in a nutrient medium at different rates.
- Amniocentesis: the results of the study can be found in 14-20 days.
Consequences of tests for the course of pregnancy
Non-invasive diagnostic methods are considered absolutely safe for the mother and for the unborn child and exclude any adverse consequences after their implementation.
Invasive studies have some risks, so they are not recommended in case of a threat of spontaneous miscarriage, at elevated body temperature and inflammatory diseases of the organs of the reproductive system of the expectant mother.
Diagnostic methods:
- Chorionic biopsy– a relatively safe procedure, the risk of miscarriage after the procedure is less than 1%.
- Amniocentesis does not cause any complications in healthy women. If the pregnancy initially proceeds with complications, the procedure can cause spontaneous abortion, placental abruption, early discharge of amniotic fluid.
Genetic tests after a missed pregnancy
Pregnancy, during which there is a stop in the development of the fetus and its death, is called frozen. It can be caused by a number of reasons, including genetic abnormalities of the fetus that are incompatible with life.
For women who are faced with a missed pregnancy, but planning to have children in the future, doctors recommend:
- To identify the cause of death of a frozen fetus by histological analysis of tissues to assess the risk of recurrent miscarriage in subsequent pregnancies.
- To undergo a genetic examination for both partners, with its help, doctors determine whether the couple has any chromosomal abnormalities that prevent conception and successful bearing of the fetus.
Based on the data obtained, the doctor selects an adequate treatment, following which will ensure successful conception with a high chance of having a healthy child. In the event that genetic analysis reveals chromosomal abnormalities in any of the parents that prevent a successful pregnancy, the birth of a child will be possible with the help of modern reproductive technologies.
Prices for genetic tests
Mandatory screening tests and planned ultrasound of the fetus are free of charge in the direction of the local gynecologist. With appropriate indications, other studies can also be carried out according to the quota.
In private medical institutions, the cost of genetic tests can vary significantly, it depends on the region and the pricing policy of each particular clinic.
The average data looks like this:
- screening of the 1st trimester of pregnancy - from 1500 rubles;
- "triple" test - from 1500 rubles;
- chorion biopsy - 5000 - 30000 rubles;
- amniocentesis - 4500 - 8000 rubles.
A person has 23 pairs of chromosomes, which are twisted strands of DNA that carry genetic information. Changes in the number of certain chromosomes can lead to the birth of children with genetic diseases. Today there are more than 6500 of them.
Many of the genetic pathologies are sex-linked - inherited by gender. In such cases, the determination of the sex of the child is carried out for medical reasons.
NIPT involves the isolation of fetal DNA from the blood of a pregnant woman and its subsequent analysis in order to identify the presence of common chromosomal syndromes. The method appeared in Europe about 20 years ago, which marked the beginning of a new era of effective methods for determining the genetic defects of the fetus - without interfering with organs and tissues. Prenetix is one of the types of non-invasive diagnostics of fetal chromosomal pathologies.
Purpose of the study:
- to determine the presence of a pathology of chromosomes 21, 18, 13 in the fetus, as well as the presence of additional chromosomes X and Y
- determine the sex of the baby
Deadline:
at the full tenth week of pregnancy
Training: not required, 20 milliliters of venous blood is enough to conduct
Getting results:
within 12 business days
Accuracy: 99,9%
Safety: 100% for the health of women and children. Blood for analysis is taken from a vein, so there is no risk of miscarriage or infection, as in the case of invasive diagnostics. The World Health Organization recommends it to every pregnant woman.
Availability: now Prenetix can be taken in Kaliningrad, in the reproduction clinic "Genome"
At the Genome-Kaliningrad clinic, any pregnant woman who wants to receive reliable information about the health of the unborn baby, as well as find out its gender, can take the Prenetix test.
Features of the Prenetix test:
- shows the exact result in a twin pregnancy, surrogate motherhood, pregnancy resulting from IVF, incl. using donor eggs or sperm.
- will show the exact sex of the child from ten weeks, including with a twin pregnancy. On ultrasound, sexual signs are noticeable no earlier than 23 weeks.
Prenetix - a worthy alternative to the classic screening of the first trimester. In some cases, it avoids unnecessary invasive diagnostic methods.
The usual screening examination in the first trimester includes:
- fetal ultrasound. It helps to detect deviations in the physique and anatomy of the unborn child, to assess the condition of the placenta, umbilical cord, uterus, the amount of amniotic fluid.
- Double test (blood chemistry)
. It is used to determine the level of pregnancy-associated plasma protein (PAPP-A) and human chorionic gonadotropin (β-hCG). With pathologies of the fetus, the levels of these substances change.
The disadvantage of this study is a high percentage of false positive results, which is an indication for invasive studies. Invasive methods involve obtaining biological material for laboratory testing by penetrating into the uterus through a puncture (puncture). Invasive methods are often accompanied by complications and can provoke a miscarriage. The condition of a woman during the period of waiting for an invasive study and during its implementation is usually stressful, which is highly undesirable.Prenetix detects the presence of the following pathologies:
- Down syndrome. Severe mental retardation and birth defects. The most common chromosomal pathology.
- Edwards syndrome . Oligophrenia: pathologies of the skull, brain, chest, heart. Up to 5% of newborns with Edwards syndrome survive to one year.
- Patau Syndrome . Severe malformations, out of 100 children, 5 survive to a year.
- Klinefelter syndrome . Male disease: pathologies of the endocrine system, infertility, impotence.
- Turner syndrome . Female disease: infertility, physical retardation, tendency to obesity and heart disease.
- Extra X and Y chromosomes . Slight deviations in mental and / or physical development.
Prenetix may show a false result in the following cases:
- Pregnancy with more than two fetuses;
- The duration of the study is less than two weeks;
- The death of one of the twins.
Prenetix is indicated in the following cases:
- "bad" result of the first screening;
- the presence in the anamnesis of pregnancies with chromosomal mutations of the fetus;
- late reproductive age of future parents (mother from 35 years old, father from 42 years old);
- revealed chromosomal abnormalities in future parents.
Note: The risk of genetic disorders in the fetus increases with age, but it is not excluded in the period up to 35 years. By law, a doctor is required to inform a woman over thirty-five years of age about the possibility of conducting an intrauterine screening test to detect malformations of the child.
Over the past 25 years, the number of women who have become mothers over the age of 35 has increased by 90%. If fifteen years ago, twenty-five-year-old women in childbirth were called the unpleasant word "old-timer", today the "late" age has shifted to 35.The specialists of the clinic "Genome" in Kaliningrad have an impressive experience in managing pregnancy, including complex cases. We will be happy to help every woman to go through the pregnancy safely and become a happy mother of a healthy child.
