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In case of undeveloped pregnancy
In case of undeveloped pregnancy
Molecular genetic study of abortive material for chromosomal abnormalities
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Across Georgia
12 working days
From the moment the sample arrives at the laboratory
Valid result
Checking both fetal and maternal tissues
Molecular genetic study of abortive material for chromosomal abnormalities
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Lots of women face loss of pregnancy. About one in five pregnancies finishes in developmental stop, spontaneous miscarriage or stillbirth. More than 50% of all pregnancy losses are related to chromosomal aberrations in the embryo. Mostly, such anomalies are accidental and do not repeat in further pregnancies.
Awareness of the cause of pregnancy loss assists in estimating the risks of relapse and planning tactics to get ready for the next pregnancy.
Molecular analysis identifies chromosomal aberrations and gives an opportunity to understand if the loss of pregnancy was a random event, or a more comprehensive checkup is required.
Chromosomal aberrations
About 1 out of 2 cases of early pregnancy loss is caused by an error that happens within the formation of germ cells, or at the time of fertilization. As a consequence of such a mistake, the embryo has an irregular number of chromosomes. This is referred to as a chromosomal abnormality. Chromosomal abnormalities arise accidentally. This implies that the loss of pregnancy is not due to the fact that the woman did something wrong.
Unluckily, such an event cannot be predicted and prevented.
In some cases chromosomal aberrations can be transmitted from parents and cause repeating pregnancy losses in a couple. The reason is that one of the partners part of one chromosome sticks to another one. It is called a balanced chromosome translocation. Usually there is no physical signs or symptoms for people with a balanced chromosomal translocation, but when germ cells (eggs or sperm cells) are formed, some of them contain abnormal chromosomes. A chromosomal disorder develops if the embryo is formed from such germ cells.
Chromosomes are structures that are located in organism cells and comprise genes that determine the physical condition of a person.
Normal cells include 46 chromosomes (23 pairs)
Germ cells include 23 chromosomes
Quite often chromosomes are allocated irregularly during the formation of germ cells and cell there may comprise, for instance, 24 chromosomes, instead of 23.
At the time of fertilization, when the egg and sperm join, two sets of chromosomes meet. If an egg or sperm carry the abnormal number of chromosomes, then the chromosome set of the embryo will be irregular as well.
Based on the difference between the chromosome set and the normal one, three end results are likely:
1. The embryo development failure even before the pregnancy manifest. Pregnancy does not happen.
2. Pregnancy comes about, but the embryo develops irregularly. As a result failure of pregnancy.
3. A baby with a chromosomal syndrome, a serious incurable disorder, is born, for example, with syndromes Patau, Edwards or Down.
A woman of any age, with any state of health and lifestyle, can meat chromosomal disorders in fetal tissues, but the risk of such disorders rises considerably due to a woman’s age. Risk of spontaneous miscarriage at age:
- 1 out of 8 from 20 to 30 years old,
- 1 out of 5 at age 35,
- 2 out of 5 at age 40,
- 4 out of 5 at age 45.
Indications
About a half of first trimester pregnancy losses are the result of a chromosomal disorder. That’s why the study is most appropriate for early pregnancy loss. In later pregnancy, chromosomal abnormalities tend to lead to multiple malformations. If there are no malformations, then a chromosomal disorder is less likely. So the analysis is more meaningful in cases where the obstetrician-gynecologist assumes chromosomal abnormalities of the fetus.
The study will contribute to realize the reason of the pregnancy failure, this will inlarge the opportunities of preventing repeated event. The results of the analysis should be speaked to the doctor. In the following cases, the study will be most appropriate:
- Pregnancy termination for medical reasons in case of detection of multiple malformations in the fetus;
- Recurrent pregnancy loss, especially if no study after the previous event was performed.
Workflow description
Molecular genetic study of abortive material for chromosomal disorders is conducted in the laboratory on the Ion GeneStudio S5 System using the ReproSeq kit.
In the course of the study fragments of fetal tissues from abortive material are selected. Careful washing from fetal tissue from maternal tissue followed by DNA extraction and sample prepararion for sequencing. Thereafter NGS assay is performed. Reads are analyzed acsoss whole genome, it means the study does not affect separate sites, but entire chromosomes. Due to this technology we have a possibility to see if any chromosome or its fragment is too overrepresented or too underrepresented.
Chromosomal abnormalities are searched as the result of sequencing. In the presence of segmental abberations (not the whole chromosome amount change, but its part), this event is estimated in terms of its value for the course of pregnancy. Only critical events that could affect the undevelopment of pregnancy are included in the report.
It is important to investigate embryo DNA of the embryo for chromosomal abnormalities looking for. But embryo tissues can be mix up with the mother’s, giving mixed DNA in abortive material and deforming result report. If there are doubts about the purity of a sample of fetal DNA, additional study is performed to see if there is an admixture of mother`s DNA. During the analysis DNA in the sample and the DNA obtained from the mother’s blood are compared.
If the fetal and maternal DNA are mixed, new portion of the fetal tissues is selected and the study is repeated one more time. In certain cases (about 1 out of 20 of samples), the laboratory receives samples that don’t have any fetal tissue, but only maternal. In such situations, the study is impossible, and the laboratory returns the money.
Significance of the result
As an analysis result you will get the information about the chromosome set in the fetal cells, if the set is normal or if not, what change is presented.
A consulting with a geneticist is recommended for correct interpretation of the result and understanding of further actions.
A doctor makes a conclusion whether the loss of pregnancy was an random event, counts the personal risks of recurrent pregnancy loss. In certain cases a doctor may suggest karyotyping. This analysis defines the number and structure of chromosomes. Karyotyping can identify a balanced chromosome translocation that can be a probable reason of recurrent miscarriages.
In the case when a chromosomal translocation is identified, the geneticist may recommend in vitro fertilization (IVF) with special genetic assay — preimplantation genetic testing for aneuploidy (PGT-A). This approach makes it possible to choose an embryo with a normal number of chromosomes to transfer it into the uterus.
Pros
Studying all the chromosomes
The entire set of chromosomes is analyzed, not selected ones. This makes it possible to identify an irregular number for any chromosome, as well as to find segmental aberrations with a size of 5 Mb or more.
Fast result
The study is performed in 12 working days after delivering the sample to the laboratory.
Valid result
The laboratory once again checks that embryonic and not maternal tissue have been obtained for the study. For making this possible, it is required to get the mother’s blood as well.
There is no need of viable cells in the material
It is significant when the development of pregnancy stopped some time ago, and there are no longer viable cells in the tissues.
How to get the study
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How to get the study
If it happened that the pregnancy was interrupted, collect the material in a clean container and call our carrier by phone +995 32 211 00 50.
+4 °C Tissues can be hold in the fridge
- As a rule, biological material for transportation is collected and prepared in the clinic the patient applied to. It is suggested to collect once again the mother’s blood from a vein into a tube with a purple cap (tube with EDTA).
- In certain cases, such as surrogacy, using donor eggs, organ and tissue transplants, the blood of the biological father is required.
- This is necessary to make sure that fetal, and not maternal, tissue have been obtained for the study.
- The material from the clinic will be transfered to the laboratory by ourselves. Please let us know if transportation is required timely. It can be done by a clinic staff member or the patient personally by calling +995 32 211 00 50.
- For storage and shipment of the sample, the use of a special preservative buffer from the KROMOS laboratory is suggested.
- If the clinic does not have the preservative buffer, sterile saline can be used. The material is advised to be stored at +4 °C.
- The study is performed within 12 working days from the date of receipt of the material by the laboratory. The result is sent by the email specified in the application for the study. To interpret the results of the study, it is suggested to consult a geneticist.
Loss of pregnancy
Women face a loss of pregnancy much more often than many people suppose.
From 1/10 to 1/5 of pregnancies stop in loss of pregnancy
But the actual quantity is even greater due to many miscarriages that happens so early in pregnancy that the woman doesn`t know she is pregnant. Most miscarriages take place as a result of fetal developmental disorders. And although loss of pregnancy is relatively common event, it does not make it any easier. Realizing why this might have occured helps a deal with such a loss.
As a rule, loss of pregnancy is a single event.
Most women who face it go through healthy pregnancies and childbirths in the future. Less than 1 out of 20 women encounter two consecutive losses of pregnancy, and only 1 out of 100 encounters three or more. If you face two or more losses in a row, it is recommended to figure the reason of these events out. But even if the reason cannot be determined, don`t stop hoping. Approximately 7 out of 10 women with unclear repeated losses of pregnancy can carry a healthy pregnancy.
7 out of 10 of women with unclear repeated losses of pregnancy can have healthy pregnancies
There are a lot of causes of pregnancy termination.
There is not always an opportunity to determine why exactly the loss occurred. Most cases of pregnancy loss are not due to the fact that the woman did something wrong. And alas, most cases of pregnancy loss cannot be avoided. Hard work, exercises, an active sex life, or taking oral contraceptives before pregnancy does not lead to miscarriages. Early toxicosis does not interfere the pregnancy success as well. The women who came across early pregnancy loss convinced it is due to a recent fall, worries, or stress. In most cases, it`s not true.
Majority of cases are not related to the fact that the woman did something wrong
The main reasons are:
1. Genetics
~a half About a half of the events are associated with chromosomal disorders of an embryo.
2. Particular women’s health states
Among them infectious diseases, uncontrolled diabetes, hormonal disorders, structural features of the uterus, thyroid disease, antiphospholipid syndrome.
3. The usage of certain drugs
The use of some drugs, as well as smoking more than 10 cigarettes a day and drinking moderate amounts of alcohol, may be connected with loss of pregnancy. During pregnancy, it is preferable not to smoke or drink alcohol, and not to exceed caffeine intake of more than 100 mg per day (4-5 cups of coffee). Before taking any drugs, it is advised to carefully check the instructions for information on the possible use of the medication during pregnancy. It is recommended to avoid exposure to occupational hazards whenever possible.
Majority of cases of pregnancy losses come about prior to 12 weeks
Signs of miscarriage:
- Bloody issues or vaginal bleeding
- Abdomen or lower back pain
- Fluid or tissue getting out from the genital tract
If a miscarriage has happened, put the fetal tissue in a clean container and deliver it to your physician. It`s required to conduct a study, for the reason of pregnancy loss finding out and estimation the risks of repeat of this event.
I need help
Pregnancy loss may be an exceptionally hard and traumatic event, despite the timing or situation when it happened. Let yourself experience this loss and accept what occurred in order to move on.
After a pregnancy loss, you may feel a variety of emotions, and it`s normal:
- Negation. At first, it may be very hard to realize what has occurred and to believe that it has happened, indeed..
- Guilt. You may reflect on what you could have done in a different way to avoid the pregnancy loss.
- Anger. Despite the causes why this came true, you can get mad at yourself, your partner, the doc, or fate. You may be mad at the injustice of your loss.
- Sadness. You may feel grief or an intense wish to be with your baby. You can envision what you would do with your baby right now.
- Envy. You may feel strong envy of people who are going to be parents. It may seem to you that babies and pregnant women are everywhere.
- Depression. You may have progression of depressive signs, such as a loss of interest or joy in your habitual activities. Your food habits or sleep schedules may alter, and you may have problems with decision making or concentration.
Other family members may face the same feelings — anxiety, loss, and a helpless feeling.
- Mourning and acceptance demands time.
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Certain emotions may pass immediately, or not arise at all, while others may be delayed. Even if you feel like you’ve gotten over your loss, you may come back to the situation and feel anger or guilt. You may find it hard to meet friends who have children, and that’s okay. Don’t blame yourself and try to insulate yourself from such painful situations until you feel ready to move on.
- Feel free to ask for and accept help from friends and family members.
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Try to attend a support group. Sharing the feeling of loss with others who have experienced the same can support you. It can be both face-to-face support groups and online communication. If the mourning seems to be prolonged, or you are unable to cope with daily routine, request professional psychological support.
- Plenty of women who faced pregnancy loss later go on to have successful pregnancies and deliveries.
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When the pain of your loss has faded, you can talk with your partner if you are ready to try again. The next pregnancy can cause sorrows due to the loss of this pregnancy, but it can also give hope for the future.
Links
Royal College of Obstetricians and Gynaecologists, UK
American College of Obstetricians and Gynecologists, USA
International Federation of Gynaecologists and Obstetricians, London, UK
Dictionary
- DNA
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A molecule located inside the cells of the body that keeps data about inheritance. This data is encoded in DNA by connecting into a chain of small molecules — nucleotides, which can be of four types. Data is recorded in the same way that we make text up of symbols, but there are only four letters in the DNA alphabet.
- Gene
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A section of DNA that contains the answer to one particular task for a cell, for example, a way for making a specific protein.
- Genome
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All information about heredity in a cell
- Mb (megabases)
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Measurement unit for DNA fragments is 1 million nucleotides — the “letters”of which DNA is made. Humans may have the size of one gene that can vary from several hundred nucleotides to several Mb. The genes are located unevenly, and the space between them can be practically absent, or ,instead, can reach tens of Mb. That’s why the size of a DNA section is not directly associated with its significance for the organism life.
- Balanced chromosomal translocation
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A rearrangement when two chromosomes are exchanged in fragments. As a rule, such a rearrangement has not clinical manifestation itself in any way, as the complete set of genetic material is saved. But in the process of germ cell formation, the chromosome set is divided in half, and consequently, the egg or sperm can receive an irregular, unbalanced chromosome set.
- Segmental chromosomal disorder
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A chromosomal aberration when not the whole chromosome, but its segment is absent or over represented in the cells. Due to the size of the segment and to what genes it contains, such an irregularity may not manifest itself, but may result in a chromosomal syndrome or a stopping in the development of an embryo.
- Sequencing
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Determining the sequence of nucleotides in DNA. Comparing the DNA sequence in a sample with a standard human sequence gives you a possibility to see if there is a disorder in the sample.
- Chromosome
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Structures in which DNA is kept in a cell. DNA is a long and thin molecule. When a cell splits, it needs to share all the DNA evenly between the two new cells. In order for the thin strands of DNA not to become tangled or torn, they are folded into dense compact bodies — chromosomes. Mostly human cells contain 46 chromosomes — 23 pairs. One set of 23 pieces is derived from our mother, the second one from our father. Germ cells contain 23 chromosomes, and when fused with a second germ cell, they form a complete set of 46 chromosomes.
- Chromosomal abnormality
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Any change of the chromosome set from the normal set of 23 chromosome pairs.
- NGS
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Next-Generation Sequencing, high throughput sequencing.
A sequencing method when a DNA sequence is read in parallel for a huge quantity of short pieces. Then, on the computer, the overall picture is assembled from these pieces. This method makes it possible to study in a short time not just a single section of DNA, but vast fragments and even the whole genome.
The pros at Kromos
Privacy
All data is strictly confidential and cannot be shared with third parties.
Technology
The NGS method makes it possible to analyze all the chromosomes of the embryo, as well as to identify mosaicism and unbalanced chromosomal rearrangements
Reliability
Quality control at each stage of the study
Free shipping
Delivery of biomaterial throughout Georgia
Consultation
Possibility of online consultation on the results of the study
Balanced chromosomal translocation
A rearrangement when two chromosomes are exchanged in fragments. As a rule, such a rearrangement has not clinical manifestation itself in any way, as the complete set of genetic material is saved. But in the process of germ cell formation, the chromosome set is divided in half, and consequently, the egg or sperm can receive an irregular, unbalanced chromosome set.