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How to find out who the father is without DNA. How to check paternity with the maximum accuracy of the result? What is needed for this
Includes a series of procedures aimed at clarifying the existence of a family relationship between a man and a child. There are several main methods for establishing paternity: by resemblance (eye color, facial features), blood type, date of conception, and also by DNA analysis. The latter method is the most reliable and can be presented as evidence in court. Paternity is usually established by a geneticist.
Methods for establishing paternity
Methods for establishing paternity vary in the degree of complexity, reliability of the results and the value of the data obtained in terms of the possibility of their use as evidence in court. Below are the most well-known methods for determining paternity:Determination of paternity by external signs
External signs, such as eye color, hair and skin color, similarity of facial features, etc., cannot serve as a reason to confirm or deny paternity. This is due to the fact that although external signs are determined genetically, they can nevertheless vary and manifest themselves to varying degrees from case to case. The inconsistency of the method of determining paternity based on the external similarity of a child and a man is also confirmed by the fact of the existence of so-called twins - people who have no family connection, but at the same time are very similar to each other in external data. Thus, on the basis of whether or not a child is similar to his alleged father, it is impossible to determine the relationship between a man and a child.Establishing paternity by date of conception and gestational age
The need to establish paternity often arises in cases where a woman had sexual relations with different men during 1 menstrual cycle. In such situations, for a preliminary and inaccurate determination of paternity, one can try to calculate the date on which the maximum probability of conception occurred. A man who had sexual intercourse with a woman shortly before or after this date is most likely the father of the child. It has been determined that in women with a regular menstrual cycle, the maximum probability of conception occurs in the middle of the menstrual cycle, that is, approximately 14-15 days after the start of the next menstruation. However, as practical observations show, for many women the moment of maximum probability of conception cannot be determined accurately. A detailed description of how to determine the likelihood of pregnancy at different periods of the menstrual cycle is presented in the articles and. Determination of paternity based on a comparison of the possible date of conception with the date of sexual intercourse is greatly complicated by the fact that spermatozoa (male germ cells) can "survive" in a woman's body for 3-5 days after intercourse. This means that conception can occur several days after sex, and that the father of the child can be a man who had sexual intercourse with a woman a few days before the possible date of conception, even if the woman had sex with another man on the very date of conception. Determination of paternity is also possible on the basis of the term (age of pregnancy). The gestational age can also be determined by ultrasound, but even with the most advanced ultrasound equipment, it is extremely difficult to determine the date of conception to the nearest day. Cm. . Thus, determining paternity based on the possible date of conception or gestational age is completely impossible in cases where a woman has had sexual intercourse with different partners within a short period of time.Determination of paternity by blood type
Blood type paternity testing is a preliminary method for assessing the likelihood of a blood relationship between a man and a child. When using this method, a negative result is 99% accurate, while a positive result can be quite inaccurate. Due to the fact that the determination of the blood type of the child is carried out mainly after his birth, the method of determining paternity based on the study of the blood groups of the parents and the child is used only after the child is born. The principle of determining paternity by blood type and Rh factor (Rh factor) is that the blood type of a child is determined by a set of genes that are transmitted to him from his father and mother. Below is a table by which you can determine which blood type a child can have, depending on the blood type of his parents. How to use the table: the mother's blood group is indicated vertically, the father's blood group is indicated horizontally. In the cell of the table, located at the intersection of the blood groups of the mother and father, the blood types that the child may have are indicated.|
Father's blood type |
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| Mother's blood type | ||||
| I(0) | ||||
| II(A) | ||||
| III(B) | ||||
| IV (AB) | ||||
|
Father's blood type |
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| Mother's blood type | ||
| Rh+ | ||
| Rh- | ||
Paternity determination based on DNA analysis
DNA paternity test is currently the most accurate and valuable method, as its results are very accurate and can be presented as evidence in court. The principle of establishing paternity based on a DNA test is as follows: In the DNA of each person there are special sequences of chemicals that are almost unique (that is, individual for each person). At the time of conception, the baby receives genetic material (unique sequences) from both parents. DNA analysis allows you to determine whether there are unique DNA sequences of a possible father in the DNA of a child. The most accurate DNA test results can be obtained if biological material (such as a blood sample or cell scraping) from the child, the alleged father and mother is submitted to the laboratory for analysis. However, if it is not possible to obtain material from the mother, the results will still be sufficiently substantiated and reliable. The accuracy of the DNA test is 100% for a negative result and 99.9% for a positive result. For DNA analysis, an insignificant amount of biological material is required: as a rule, it is blood from a vein, scraping from the mucous membrane of the inside of the cheek, hair, or nails. Since these materials can only be obtained from a newborn child, a DNA test using them is carried out after the birth of the child. As a rule, a DNA test is carried out within 14 days. If an urgent result is needed, the test is carried out in 3 days. Some laboratories provide home DNA testing services. The data obtained as a result of a home DNA analysis cannot be presented as evidence in court, but it will help dispel, or vice versa, confirm the doubts of one of the child's parents.Home DNA Paternity Test
To perform a home paternity test, you must contact the laboratory that provides this service. The laboratory will send you a kit with the necessary tools for sampling biological material, as well as detailed instructions for its use. After sampling, the biological material is sent by mail to the laboratory, where DNA testing is carried out. As a rule, the results come 3 days after the material is received by the laboratory.Is it possible to accurately determine paternity before the birth of a child?
In cases where paternity must be established before the birth of the child, DNA testing is used using biological materials from the fetus, which can be obtained as follows:- A biopsy of the chorionic villi is carried out for a period of -. To obtain the biological material of the fetus, the doctor, under the control of an ultrasound machine, inserts a needle through the vagina or the anterior wall of the abdomen, reaching the fetal membrane (chorion). The risk of miscarriage resulting from this procedure is less than 1%.
- Amniocentesis is a procedure for obtaining amniotic fluid (amniotic fluid) for genetic testing. Amniocentesis can be performed at term -. The amniotic fluid sampling procedure is carried out by a gynecologist: under the control of an ultrasound machine, the doctor inserts a long thin needle through the skin of the anterior abdominal wall, penetrates through the uterus and takes the required amount of amniotic fluid for examination. The risk of complications and spontaneous termination of pregnancy as a result of amniocentesis is less than 1%.
- Cordocentesis is performed at a gestational age of more than -20 weeks. During cordocentesis, fetal blood is taken from the vessels of the umbilical cord. The risk of complications of this method is also less than 1%.
Despite the level of development of science, in particular, genetics, the cost of genetic tests for kinship remains high. And the court does not always immediately agree to satisfy the request for such an examination. Therefore, understanding how to determine paternity without DNA is still relevant.
When is the procedure necessary?
The need for this arises when it is necessary to confirm or refute kinship. There are two ways to legally resolve the issue:
- extrajudicial (voluntary);
- judicial.
The first option is implemented in the registry office and applies to cases where the father and mother at the time of the birth of their child were not married. If the mother is dead, missing, or deprived of parental rights, the father prepares a joint declaration of paternity with the guardians or with the child upon reaching the age of majority.
If there is no consent from a parent, guardian or adult child, a person who wants to legally change the state of relationship has the right to file a lawsuit to do so.
Typically, cases are considered in court when:
- a man refuses a child born in marriage;
- a man born out of wedlock wants to recognize his own;
- a woman demands child support from his father, who does not recognize his offspring;
- other.
Legislation and methodology features
According to the Law, the fact of confirmation or refutation of paternity is determined in the process of considering various evidence provided in court. Such arguments are built on the basis of physical, written evidence, the words of witnesses, the conclusions of experts, etc. The participants in the trial, when putting forward their claims or objections, are required to refer to evidence (see Articles 55 and 56 of the Code of Civil Procedure).
In theory, using the results of either method in court is acceptable. However, even scientifically objective calculations have a built-in percentage of error. Non-genetic methods have a high error. However, it is still too early to give them up. They are important in at least two cases:
- If dissenting party I am not sure in their relationship and a number of circumstantial evidence will help dispel doubts;
- If the judge refuses to agree to a genetic examination, believing that there are not enough grounds for this.
Example for the first case: a man wants to establish paternity in relation to a child from a woman who gave birth after returning from vacation. A single mother died without telling her son who his father was. The stranger who showed up in support of his claims shows photos shared with his mother, taken nine months before the birth of the child, personal letters (perhaps even with a woman's confession about her son), written later, and so on.
Example for the second case: a similar situation to the holiday romance, except that the woman was married and her husband is considered the father of the child. The mother died without confessing her past deeds. An unknown man claims. The child is well with the husband of his mother, whom he considers his father. At the same time, the widower is on the side of the child. Evidence of a love affair provided by a stranger to the court may serve as the basis for granting a request for a DNA test. Of course, this will not automatically deprive the deceived husband of parental rights, but will dot the i's regarding biological paternity.
Non-genetic methods
There is no universal list of such methods. Their application depends on various factors, in particular, ( A) goals and ( b) possibilities of real use. Let's name some of the methods.
Comparison of blood groups, Rh factor . Tables are used, where the percentage shows the ratio of the Rh factor and blood groups in parents and their offspring. The error is high. The method works great for excluding paternity under certain circumstances. So, parents with blood type I or a negative Rh factor are born children with the same characteristics.
Examining the medical record for genetic diseases . The method is indicative if there is a match in the child and the alleged father of rare hereditary diseases, if they were not observed in the maternal family.
External signs . Comparison of the appearance, body structure (adult children) allows, by identifying generic features, to ascertain kinship. Similarity is possible not only with the alleged father, but also with his ancestors. Children often look like their grandparents.
Examination of correspondence and other communication evidence . This includes the letters and photographs mentioned in the holiday romance example.
Methods for determining paternity without DNA testing are relatively accurate. They are best used in conjunction with other elements of the evidence base. A successful selection of arguments and evidence will win the case.
There are several methods for determining paternity. And not every one of them gives a 100% guarantee of the reliability of the result. Therefore, the question “How to verify paternity with the highest probability?” widespread enough. This can only be done in the laboratory. Moreover, blood analysis and DNA analysis are the most effective methods. The latter is out of competition.
How to check paternity with a blood test?
A laboratory blood test, although not the best way, with a certain degree of probability still provides an answer to the question of paternity. With a negative result, its accuracy is 99%. At the same time, a positive answer in determining paternity can hardly be considered final. Rather, it will only be an assumption that will have to be confirmed by the results of DNA studies. But more about them later. In the meantime, about the principle of determining family ties by a blood test.
A person's blood type and Rh factor are determined by their genes. Genes are inherited from biological parents. Certain combinations of blood groups or Rh factors of the parents can only have certain groups and Rh factors of the child's blood. This is the basis of the principle of determining paternity using blood DNA analysis. If a child has a blood group or Rh that is “incompatible” with a combination of similar indicators in a mother and a potential father, the result, for obvious reasons, will be unambiguously negative. Therefore, sometimes it is enough to do just such a paternity test, the cost of which is lower than the cost of a DNA examination. With a negative result, it will be enough.
How to check paternity using DNA testing?
Benefits of DNA testing for father identification:
- 100% reliable for negative, and 99.9% for positive.
- Based on paragraph 1, the results of only such an examination can be used as an evidence base in a trial.
- A simple way to take biological material for research in adults and even young children.
Mandatory conditions for performing such a study:
- Availability of the necessary equipment.
- Availability of qualified personnel.
- Selected biological material of the child, potential father and mother.
Scraping from the inner surface of the cheek is often used as a material for research. This is a humane way, quite acceptable even for a child. A small amount of blood from a vein or saliva may also be used. The essence of the examination method is based on the fact that out of 23 pairs of chromosomes, half a person receives from the mother, half from the father. Thus, the DNA of the child will always match the DNA of his biological father by 50%.
The linear section of chromosomes that carries genetic information is called a locus. With the help of special equipment, these areas are identified and analyzed, being magnified millions of times. At the first stage, the determination of those chromosomes that are inherited from the mother occurs. Then the rest is compared with the genetic material obtained from the possible father. The coincidence revealed during the comparison with 99.9% probability speaks in favor of the fact that the man whose material was analyzed is the biological father of the child.
As can be seen from the essence of determining paternity using DNA examination, for more accurate results, it is important to provide the genetic material not only of the possible father, but also of the mother.
prenatal examination
This type of study is possible, has no errors in the accuracy of the result, but involves an invasive intervention in the life of the fetus to select genetic material - the villi of the fetal membrane, amniotic fluid or fetal blood from the umbilical cord.
Examination "at home"
Some laboratories, working remotely, offer to send a set of tools and a guide for collecting biological material by mail. This material is sent back to the laboratory, where the study is carried out and an official conclusion is issued. This method has the right to life in the case of an examination conducted in private, at the request of a person. Litigation is quite another matter. More on this later.
Legal component
It has already been mentioned that only DNA research can serve as an evidence base in litigation regarding paternity. But in accordance with the current legislation, even such an examination will not always be recognized. Therefore, if you rashly do a paternity test in the first laboratory that comes across, the cost of which is not at all small, the money will almost certainly be thrown “down the drain”. In order for the results to have full legal force, you need an official order of the judiciary on the need to undergo such an examination.
The manner in which samples are taken for examination is also a significant factor taken into account by the judiciary. Thus, an examination carried out with samples taken at home cannot have legal consequences.
Situation.
The initiator of the examination is the father. The child is a minor. In this case, to obtain the biological material of the child, a notarized consent of the mother will be required. In this, and any other cases (if necessary or if you wish to perform a paternity test), you must first consult with a lawyer. A family law specialist will help you avoid possible misunderstandings due to the nuances of the law.
Thank you
Establishing paternity involves a series of procedures that are aimed at determining the relationship between a child and a man, presumably being his biological father.
Medicine operates with several basic methods for determining paternity. They differ in the technique and degree of complexity, in the materials used in the process, and of course, in the reliability of the results obtained. As a rule, studies related to the establishment of paternity are carried out by geneticists. In doing so, they use the following methods:
- by date of conception and gestational age;
- according to external signs;
- by DNA analysis.
Determination of paternity by date of conception and gestational age
By date of conception
Often, if during one menstrual cycle a woman had sexual intercourse with several men, it becomes necessary to establish paternity. In such situations, for the purpose of a preliminary and very inaccurate determination of paternity, you can try to calculate the specific date on which the maximum chance of conception occurred. Accordingly, a man who had sexual intercourse with a woman shortly after or before this date has a high probability of being the father of the child.It is known that if a woman has a regular menstrual cycle, then the maximum probability of conception occurs in the middle of the menstrual cycle, approximately 14-15 days from the start of the next menstruation. But as practical observations show, the moment of maximum probability of conception in many women is quite difficult to accurately determine.
Establishing paternity by comparing the possible date of conception and the date of sexual intercourse may be incorrect for another reason. The fact is that spermatozoa can retain their activity and ability to fertilize in the female body for 3-5 days after intercourse. And this means that conception could occur a few days after sexual intercourse. In this case, the father of the child may be a man who had sexual intercourse with a woman a few days before the optimal date for conception. A similar situation is possible even if a woman had sex directly on the date of conception with another man.
By gestational age
Establishing paternity is also possible by determining the gestational age, which can be approximately measured according to the indications of an ultrasound examination. However, even the most advanced ultrasound equipment is not able to set the date of conception with high accuracy, and indicate a specific date.Thus, establishing paternity based on determining the possible date of conception or measuring the gestational age is an extremely approximate and unreliable method. It can only have a complementary value. In addition, this technique becomes practically useless if a woman has had sexual intercourse with various partners for a short period of time.
Determination of paternity by external signs
Various elements of a person's appearance, such as the color of hair, eyes or skin, similarities in facial features, etc., can only serve as an indirect, and very unreliable reason for refuting or confirming paternity. This is explained by the fact that, although external signs are set genetically, they can vary widely and have different degrees of manifestation in each case. In addition, the inconsistency of the method of establishing paternity based on the external similarity of a man and a child is confirmed by the fact of the existence of twins. This is the name of people who do not have any family ties, but at the same time are very similar to each other in their appearance.
Determination of paternity by blood type
There are over 20 different blood group systems in the human population. Only two of them are most commonly used:1. AB0 system. Most often, it is this system that is meant when they talk about "blood type".
2. Rh factor. Differences in the Rh factor of the blood.
Both of these systems of dividing blood into groups are genetically determined and, therefore, open up some possibilities for determining paternity. The very principle of establishing paternity by the Rh factor and blood group is based on the fact that the parameters of the child's blood depend on the set of genes that the mother and father will pass on to him.
AB0 system
In this system, 4 blood groups are distinguished:- I or 0 (zero);
- II - A;
- III-B;
- IV-AB.
Determining paternity based on a blood type cannot be considered an accurate method, although it has greater reliability than those described above. This technique is considered rather indicative, and is used as a screening preliminary study before conducting a DNA test. A blood test provides irrefutable evidence only in rare cases. For example, if the child has I blood type, and the father has IV.
Rh factor
According to the system of Rh factors, only two groups are distinguished - Rh-negative (Rh-) and Rh-positive (Rh +). Accordingly, their difference lies in the presence or absence of specific antibodies (Rhesus factor) in human blood.The establishment of paternity by the Rh factor is less reliable than on the basis of the AB0 system. Even Rh-positive parents can have a child with Rh-negative blood. However, with Rh-negative parents, the child will also always have a negative Rh factor. Therefore, the only case when it can be unequivocally stated that a man is not the biological father of a child occurs in a situation where both parents have a negative Rh factor, and the child is positive.
Determination of paternity by blood type serves as a preliminary method for assessing the presence of consanguinity between a child and a man. The peculiarity of this method lies in the fact that a negative result will be 99% accurate, and a positive one is practically not significant. In addition, this analysis can be carried out only after the birth of a child, when it becomes possible to examine his blood type.
Determination of paternity by DNA
Sometimes in life situations arise when it is necessary to establish the degree of relationship of people with a sufficient degree of certainty. This includes cases that are related to family reunification, solving various legal problems, researching the compatibility of fabrics, etc. Just a few decades ago, such a task was solved with great difficulty and extremely doubtful reliability of the results. But after biologists learned to decipher the DNA code, genetic research methods were created that made it possible to answer with high accuracy the question of whether there is a biological relationship between two people. Including similar technologies are used in determining paternity. Each person carries a completely unique genetic information. It is encoded in DNA (deoxyribonucleic acid). These giant molecules are present in any cell of the human body that has a nucleus. DNA molecules are organized into complex structures called chromosomes.
Each of the chromosomes is contained in each of the somatic cells in two copies. The Greek word "soma" means "body", so the cells that make up the human body are called somatic. The only exception - non-somatic cells - are sex cells: spermatozoa in men and eggs in women. They differ from somatic ones in that in them all chromosomes are not contained in pairs, but only in the singular.
Why did nature provide for such a difference? As you know, at conception, the spermatozoon merges with the egg and the union of their chromosome set, that is, the genetic material that they contain. The child receives one chromosome from each pair from the father (the sperm chromosome), and the second from the mother (the egg chromosome). In this way, the child receives a complete chromosome set, and inherits the gene material of his parents - therefore, he often looks like them. But on the other hand, combinations of male and female chromosomes can be formed in billions of different options - this is what determines the individuality of each person.
DNA analysis to determine paternity
This method is based precisely on this duality of the child's DNA: on the one hand, it is unique in its own way, on the other hand, it arose as a result of a combination of parts of maternal and paternal DNA. Modern technologies of molecular genetic research allow doctors to identify maternal and paternal DNA components in any person. In addition, it is possible to trace the transmission of certain DNA fragments in mother-child or father-child pairs. Indeed, in the case of confirmation of relationship, DNA fragments in the compared pairs coincide almost completely.Legal significance
A DNA paternity test is considered so reliable that its results even have official legal force. According to the Order of the Ministry of Health, to prove the fact of paternity, it is enough to conduct a study with an accuracy of 99.90%. Modern technology allows you to achieve even greater accuracy, but most often this is simply not necessary. A correctly calculated probability of paternity, equal to 99.90%, is quite sufficient to use the wording adopted in the scientific world and legal practice: "paternity is practically proven." The exclusion of the fact of paternity in order to recognize it as legally significant requires obtaining at least three discrepancies between the studied DNA fragments of the child and his alleged father.
It should be remembered that without material taken from the mother of the child, it is more difficult to achieve the level of necessary reliability of the study than in the case of testing all family members. That is why, if a DNA examination is performed to challenge or determine paternity in court, then judges often insist on the simultaneous collection of materials from the child, his alleged father and biological mother. This is necessary so that the conclusion issued by the forensic expert does not raise any doubts.
Determination of paternity using the study of DNA molecules is an opportunity to obtain a completely reliable and scientifically substantiated result. This opinion can become an important argument in solving many legal problems, for example, in divorce proceedings and the recovery of alimony, the determination of heirs and the distribution of inheritance, immigration and many other issues.
How is the conclusion of a DNA analysis to determine paternity formulated?
After conducting a DNA analysis to establish paternity, a conclusion is issued containing one of the following conclusions:1. The result is positive– the man is NOT EXCLUDED as the biological father of this child (the probability of paternity is 99.9%).
2. The result is negative– the man is EXCLUDED as the biological father of this child (the probability of paternity is 100% excluded).
Theoretically, it is possible for another person to exist in the world with a genetic set that is absolutely identical to the genetic passport of the person being tested. For example, this situation is observed in identical twins, whose gene material matches each other by 100%. This probability is associated with a small deviation from a completely reliable positive result in a DNA paternity test. But, in the vast majority of cases, the establishment of paternity with a probability of 99.9% will mean its proof. And a negative result with the correct sampling of the material and the correct conduct of the study is always unambiguously true.
What biological materials can be used in DNA analysis to determine paternity?
DNA molecules can be isolated from many different sources. Previously, only blood taken from a vein was used to determine paternity by DNA. However, such blood samples should only be taken by a qualified healthcare professional, and in a hospital or at least a polyclinic setting. For many clients, and especially for children, this method is not always acceptable. To date, the range of materials for DNA research has expanded tremendously. Now it is possible to perform DNA analysis not only on blood from a vein, but also on hair, saliva, nails, etc.buccal epithelium
At the moment, the most preferred, easy and common method of taking a reference sample for research is the use of a buccal (buccal) swab. At the same time, epithelial cells of the oral mucosa are used for genetic analysis, which are taken on the inside of the cheek with a cotton swab. This is a non-invasive (that is, does not injure the tissues of the body) and absolutely painless method, in which the collection of material takes about a minute. In addition, it does not require the presence of medical professionals, and can be performed by the patient at a time when it is convenient for him, without even leaving home. Also, the use of buccal epithelium reduces the likelihood of contamination of the material for analysis. DNA paternity test based on non-standard samples
If taking the buccal epithelium is not possible or difficult, then other methods can be used. As a source of DNA when performing private and anonymous studies, in addition to the standard sample of buccal epithelium, almost any object containing human DNA can be used:- blood samples;
- saliva;
- teeth;
- nails;
- sperm;
- samples from tissue biopsy storage;
- rooted hair and other suitable biological tissues.
- toothbrushes;
- razor blades;
- cigarette butts;
- handkerchiefs;
- napkins;
- clothes, etc.
In addition, despite the use of the most modern methods of genetic examination, it is impossible in some cases to isolate DNA from such non-standard samples due to its complete absence.
DNA analysis to determine paternity
A control tissue sample is carefully analyzed to create a DNA profile of the person. Subsequently, this DNA profile is compared with another sample in order to determine the genetic similarity.polymerase chain reaction
To create a human DNA profile, it is not enough to simply isolate deoxyribonucleic acid from the provided material. The study will be successful only if there are enough DNA molecules, that is, a fairly large number. For this purpose, a process called the polymerase chain reaction is used. This reaction multiplies or amplifies the DNA sample that has been isolated from the starting material. The result is several billion absolutely exact copies of the same DNA obtained from a person. Geneticists are already working with this number of DNA molecules.loci research
The locus of DNA is its strictly defined part, which is subjected to research and comparison. 99.9% of the sequences found in human DNA are the same in composition, but, nevertheless, the DNA of different people carry a sufficient number of individual differences. There are parts of the DNA molecule that are unique to each person. This fact is what makes us different.The accuracy of DNA analysis is primarily affected by the number of genetic loci studied. The more sites that define our uniqueness are explored, the higher the likelihood of refutation or confirmation of paternity. Currently, it is customary to analyze from 16 to 40 different loci on each DNA sample. This provides over 99.99% confidence in establishing biological paternity, and 100% success in excluding it. In addition, often the analysis is carried out by two independent research teams, and the data obtained are subsequently verified. This procedure avoids errors associated with accidental contamination of the material, or inaccuracies when working with it.
Determination of paternity during pregnancy
Establishing paternity early in pregnancy traditionally refers to prenatal diagnosis. To determine paternity during pregnancy, it is first necessary to take biological material from the fetus. This procedure is strongly recommended to be carried out only in a specialized medical institution, since it may be associated with possible risks of complications. In the situation when paternity must be determined before the birth of the child, DNA testing is used based on the biological materials of the fetus, which are obtained as follows:
- Biopsy of chorionic villi. Material sampling is carried out at a period of 9 to 12 weeks of pregnancy. In order to obtain biological material, a specialist, under the control of an ultrasound machine, inserts a needle through the anterior wall of the abdomen or vagina, reaching the fetal membrane. The chance of abortion during this procedure is about 2%.
- Amniocentesis. The procedure for obtaining amniotic fluid (amniotic fluid) for subsequent genetic testing. Amniocentesis is most often performed between 14 and 20 weeks of pregnancy. The procedure for the selection of amniotic fluid is carried out by a specialist gynecologist. He, under the control of an ultrasound machine, inserts a thin and long needle through the tissues of the anterior abdominal wall, penetrates the wall of the uterus, and collects the amount of amniotic fluid necessary for the study. The chance of developing complications or spontaneous abortion during amniocentesis is about 1%.
- Cordocentesis. In the process of cordocentesis, fetal blood is taken directly from the vessels of the umbilical cord. This procedure is carried out at a gestational age exceeding 18-20 weeks. The chance of complications when using this method is less than 1%.
Non-Invasive Prenatal Paternity Testing
According to American scientists, they have developed a non-invasive way to determine paternity during pregnancy. Genetic testing is performed using a special technique in which a small amount of DNA is analyzed. This test can be used already in the first trimester, most often after the 10th week of pregnancy. Analysis at an earlier date does not guarantee that a sufficient amount of fetal DNA is obtained from the mother's blood plasma. Testing is carried out by examining a number of venous blood samples taken from the expectant mother and the alleged father.The prenatal non-invasive paternity test uses free-circulating fetal DNA testing. Some of it during pregnancy is in the blood of the expectant mother. Modern technologies used in genetics make it possible to isolate it and compare it with the DNA of the mother and a possible biological father.
A new non-invasive paternity test could replace the methods of fetal DNA profiling listed above, which are unsafe for mother and child health. According to scientists, it has the same high accuracy, but it is more preferable, because during its implementation there is no threat of complications and early termination of pregnancy.
Conclusion
The minimum period for establishing biological relationship and conducting research to determine paternity is 3 days. However, in most cases, qualitative analysis will require ten days to two weeks from the moment the biological materials arrive at the laboratory.Today, DNA testing can be carried out almost anywhere. There are even portable laboratories. And equipment for genetic identification of a person is produced by dozens of enterprises in many countries of the world. That is why the previously complex and exotic procedure is now becoming a common research method that anyone can use.
Before use, you should consult with a specialist.pregnancy calculators
If you are faced with a difficult choice and want to find out who the father of your unborn child is, the interactive Prompt will help you figure it out.
If you have a short term, then in order to narrow the circle of suspected paternity as much as possible, you will have to remember a few numbers. First, remember when your last period started. And secondly, what is your average cycle (the period between the beginning of the penultimate and the beginning of the last menstruation). Fill out the form and click "Next".
A bit of theory for a better understanding of the interactive prompter logic.
The most favorable for conception is the day of ovulation. On this day, the egg is released. And if unprotected sexual intercourse occurs on the day of ovulation, spermatozoa full of strength rush to meet the "fresh" egg.
The life path of an unfertilized egg ends in a couple of days. Therefore, sex two days after ovulation rarely leads to pregnancy. Spermatozoa also have limited strength, they can “wait” for an egg for five days, no more. For this reason, unprotected intercourse more than five days before ovulation is also considered relatively "safe." This is based on the calendar method of contraception (not very reliable).
When does ovulation occur?
The average woman gets her period two weeks after ovulation. In other words, ovulation occurs 14 days before the expected period.
Who is the child's father?
It is possible to determine for sure whether a man is the father of a child using a DNA test. But this can only be done when the baby is born.
How to find out who is the father of a child without a DNA test and even during pregnancy? You can ask the doctor after the next examination or ultrasound.
If you remember the day the last menstruation began and the average length of the cycle, you can try to determine for yourself who the child is from. This method does not give an absolute guarantee, but often helps to understand the origin of pregnancy.
Questions for the article
Menstruation, came a day earlier, went 6 days, a cycle of 27-30 days, after ...
Ovulation on the 17th day of the cycle approximately comes ... because I have a cycle ...
Conception. The last menstruation was 08/28/2017, the cycle was 28-30 days. First...
What is the most likely number that I am pregnant?...
Had sex with ppa. On which of these days could pregnancy occur!? ...
Menstruation has gone. I have a husband with whom we are planning a child and in ...
January 2017 I went to the gynecologist to take pregnancy tests ...
Monthly, i.e. On the 24th there was sexual intercourse, with a condom, on the 28th there was...
My partner was the interrupted act 01.12, and with the second, a permanent one, with ...
Irregular cycle after oral contraceptive, 26-30 days. April 5, 2016...
After 19.05 months came. 01.06 was an ultrasound on the issue of cystitis, they put ...
The act interrupted was 31.03, 2.04, 4 and 5.04. Last period from 14.04.- to 20.04....
The fact that I can't remember when was the last M (lost...
The man was on 03/17/16, then sexual intercourse with another young man ...
Menstruation in March was 03/16/16) and sexual intercourse on 04/21/2016. The doctor says that...
On the same day, she had intimacy with her husband, sex was not protected. these 2...
days). After there was sexual intercourse with a boy, let's call him M, but 1 ...
Menstruation 12-16.05.2016. Cycle 29-31 days. Sexual intercourse was 13.05; 05/31/2016 Uzi...
ONE, INTERRUPTED COMMUNICATION 05/12/2016 WITH ANOTHER, UNDER WHAT NUMBER OF ...
Could you get pregnant?
Measurement of basal temperature. Last M from 06/28/16 to 07/06/16. With...
01/02/2016. Ktr according to ultrasound from 02/04/2016 8mm, from 03/14/2016 60mm. What number is the most...
Coitus interruptus 15.08., full-fledged sexual intercourse 17.08....
Which one is the father of the child?
Put 13.1 weeks. ktr 67.8mm. Sexual intercourse was on 04/22/16. and 30.04.2016....
17:00, 06/29/2016 sexual intercourse at 12 o'clock at night. 07/09/2016 ultrasound of the fetal egg is not...
A week. As far as I understand, conception occurred at the end of December ...
5 days, 05.06. sexual intercourse unprotected, 23.06. The test showed bright two...
Menstruation. 8.06 was an unprotected act and 10.06 was an unprotected act...
The monthly came 2 days later, it turns out the cycle of 30 days was ...
Certificate of pregnancy. In which the last menstruation is indicated ...
There is no question who can be the father of the child. But with one...
It was our last meeting, we parted. I had my period in...
From words without an ending, subsequently a permanent relationship with ...
I had unprotected intercourse with my boyfriend, 14...
And the last were with a cycle of 29 and 32 days. PPA was 11/17/2015 with one...
I was with my beloved 5.12. , 7.12., Monthly expected 8.12. But it happened...
Were 10/01/2015 to 10/05/2015, sexual intercourse was 09/26/2015 and 03/02/2015 on 03/01/2016 ...
