Miscarriage – what factors influence a miscarriage? Interview with the director of the Institute of Mother and Child in Warsaw

Proven content

Miscarriages are a natural selection mechanism. In this way, nature removes embryos with defective genes. This happens to more than half of the fertilized eggs, says Dr. Tomasz Maciejewski, director of the Institute of Mother and Child in Warsaw.

Why does one woman get pregnant and give birth to a healthy baby, while the other experiences a miscarriage?

It is estimated that one in 2,5 thousand pregnancies ends in miscarriage. We also know that the risk of miscarriage in the first pregnancy is 5 percent. However, we are talking about documented pregnancies, i.e. pregnancies that women were aware of. Almost half of the fertilized eggs are removed naturally in the early stages of development.

So we don’t know we were pregnant?

Yes, these are the days that are several days late. Sometimes even a woman who is concerned about no bleeding will take a pregnancy test and it will come out positive, but very weak. And the next day there is blood and everything looks like a normal period. On this basis, we can assume that the woman was pregnant, but in what we call it – biochemical. So you haven’t seen the pregnancy vesicle yet, but the syncytiotrophoblast cells have been formed because the HCG hormone has come in and the pregnancy test was positive. So there was a very, very early miscarriage. As I said, this is how nearly half of the fertilized eggs end up.

And when a woman knows she is pregnant, what is the likelihood of a miscarriage?

On average, 1 in 6 confirmed pregnancies fail in the first 12 weeks of pregnancy, i.e. the first trimester, and 1 in 50 in the next 9 weeks.

Why does a woman’s body terminate these pregnancies? Are the embryos damaged?

Yes, embryo genetic defects are the most common cause of miscarriages. Our genetic material consists of millions of genes that are multiplied, so it is not difficult to make a mistake. Therefore, even in a relationship of two healthy people, there is no 100% guarantee that their embryo will be healthy. The genetic defect of the embryo is thought to account for 60-80 percent of early miscarriages.

Do we have any influence on it?

If we are carriers of a genetic defect, we can choose a partner so that – to put it ugly – our combined genetic material does not increase the risk of miscarriage. But these are just hypothetical safeguards. Remember that when an embryo is defective, its miscarriage is a method of natural selection. This is the principle of natural selection. Nature duplicates these genes, or their mutations, that are used by mankind at any given time. Sometimes we find these choices incomprehensible. This was the case, for example, with the gene responsible for cystic fibrosis. Children with cystic fibrosis, to put it simply, emit denser intracorporeal secretions. In the old days, thanks to this, they did not die of diarrhea, i.e. dehydration, which was the most common cause of death in young children. The cystic fibrosis gene thus persisted in the population, protecting against death in infancy, but also prevented people with cystic fibrosis from reaching adulthood.

What other factors make the risk of miscarriage increase?

Age certainly plays a role. A woman who turns 35 or 40 years old and decides to have the first child will have a greater risk. However, if she has given birth before, the risk of miscarriage despite her age is not much higher. The aggravating factor is addiction to alcohol, tobacco, drugs, chronic diseases such as diabetes or kidney failure, some genetic diseases, diseases of the thyroid gland, especially its hypothyroidism. The risk of miscarriage also increases in women infected with HIV, toxoplasmosis, cytomegalovirus, smallpox, rubella, herpes virus and chlamydia.

Does the working environment have an impact? Sitting behind a desk in front of a computer?

Not. But contact with chemicals, X-rays or ionizing radiation is inadvisable. But these are exceptional cases. In general, the influence of the environment on the number of miscarriages is not statistically significant. Contrary to popular belief, miscarriages are not a disease of the XNUMXst century. As I mentioned, their number per population is fairly constant. You get the impression that there are more of them, because women can find out about pregnancy quite early and see a loss that they would not have known about a few dozen years ago. The development of medicine has also influenced the fact that we are able to support medically difficult pregnancies that would otherwise undergo a miscarriage and now end in premature birth.

What about men? Do their diseases affect the termination of pregnancy?

Of course, because defective seed causes the defect of the embryo. Poor semen quality results, among others, from from environmental factors, such as alcohol and tobacco abuse, stress, poor diet, chronic or infectious diseases.

Defective genes account for 60-80 percent. miscarriages. What about the remaining 40-20 percent?

These are the diseases of the mother, father, infection. And also factors that we still can’t recognize.

After which miscarriage should we see the doctor?

It is a standard in the world that if a woman has miscarried two consecutive pregnancies, then diagnostics are introduced. We are talking then about habitual miscarriages. Remember that with each subsequent miscarriage, the risk that the next pregnancy will not be successful also increases. If a woman miscarried her first pregnancy, the probability that she will miscarry the next one increases to 20 percent.

Why don’t you look for the causes right after the first miscarriage?

Because of a few reasons. Firstly, in the case of genetic defects, it is very difficult to examine the tissue material from the miscarriage, because the separation of the tissue material of the mother and child is technologically complicated. Secondly, the risk of genetic defects in subsequent miscarriages decreases! The first pregnancy is the greatest. Therefore, when it ends in a miscarriage, the chance that the next embryo will be genetically healthy increases. So let’s wait with diagnostics.

Where should I start?

From talking to a gynecologist who should take a detailed interview, examine the parents’ general health condition, and then direct the diagnosis, including referring both a woman and a man to genetic diagnosis. should do. They can be done either in private genetic laboratories or in fertility clinics.

Let’s assume the genetic testing is fine. What’s next?

The second step is to rule out infections in both partners. These are fairly simple tests based on the collection of swabs and their analysis. It is also important to diagnose possible coagulation disorders, i.e. thrombophilia. Tests for the detection of anatomical defects of the reproductive organ. Ultrasonography, hysteroscopy, i.e. invasive endoscopic examination of the uterine cavity, or hysterosalpingography – invasive radiological examination of the uterine cavity and fallopian tubes, after prior administration of a contrast agent through the genital tract will be useful. It allows you to assess the shape of the uterine cavity and the patency of the fallopian tubes.

What about the diagnosis of immune-related infertility?

This is a topic that causes much discussion. One must remember that the fetus is a kind of transplant, a foreign tissue for the mother. The body should respond to it approvingly, but there are times when the immune response may be disturbed and the mother’s antibodies begin to reject the transplant. Then there is a miscarriage. The problem is debatable because we are not able to perform all the tests in this area, therefore there is no single standard of treatment. Immunology has ardent supporters and opponents who say that it is not 100% certain that a woman’s pregnancy is the result of immune treatment and not “the normal activities of mother nature.” Anyway, these doubts accompany many infertility treatment procedures, especially idiopathic ones, i.e. such without an unequivocal reason. You never know to what extent the patient’s pregnancy is a result of treatment, and to what extent the fact that the couple had intercourse and simply succeeded.

Are pregnancies after habitual miscarriages treated in any special way? Need to stay in the hospital, take medication, take care of yourself?

Hormonally assisted pregnancies after IVF procedures, because it is a medically induced cycle. These pregnancies are also associated with a slightly higher risk of miscarriage. But if a woman has a healthy hormone balance, she becomes pregnant naturally, then there is no reason to give her pregnancy maintenance drugs.

When does a miscarriage end and premature labor begins?

This limit is 21 weeks and 6 days of pregnancy. From that date on, we recognize that we are dealing with a premature birth. This distinction has no legal consequences. Both in the case of a miscarriage and premature birth, the parents have the right to obtain the child’s birth certificate, and if it has died, then with a note of death. On the basis of this document, parents can register their child in the Registry Office.

The more advanced the pregnancy, the more opportunities to fight for the child’s life?

In some countries, such as Great Britain, pregnancies up to the 14th week are not supported in any way. Only after this date is it considered worth fighting to maintain the threatened pregnancy. Remember, however, that between the 12th and 14th week of pregnancy, we can screen the fetus to check if it is healthy. We perform screening ultrasound examinations, the PAPP-A test. If the fetus is healthy, and one of the causes of problems with pregnancy is, for example, cervical insufficiency, then we can use prophylactic vaginal progesterone or place a cervical suture or a special pessary on the cervix.

The 14th week of pregnancy is a long time. It is impossible to check in advance whether the child is healthy?

Medicine is making great strides. There are already methods available on the market to analyze the DNA of the baby circulating in the mother’s blood as early as the 9th week of pregnancy. The cost of performing such a non-invasive panel of tests that screen the most common genetic defects costs $ 1000 for the time being, but their price will probably drop significantly over time and they will be more affordable.

What are you entitled to?

1. You have the right to register your child with the registry office. In such a situation, the hospital issues the so-called a written notification of the birth of a stillborn child. Every child (medically a fetus, embryo) is entitled to it, regardless of the time of termination of pregnancy. At the Registry Office, you will then receive an abbreviated birth certificate of the child with the note that the child was still born. A death certificate is not prepared. A birth certificate with an appropriate annotation is also a death certificate.

2. The right to register also applies to those children who were miscarried / born at home.

3. The right to register a child in the Registry Office also applies to children who have been miscarried / born outside Poland, even if the state in which the miscarriage / childbirth took place, this law is limited, for example, due to the duration of the pregnancy.

4. You are entitled to maternity leave (or maternity allowance if you are on parental leave). In the event of a stillbirth, the woman is entitled to 8 weeks of leave. The paper should present an abridged copy of the child’s birth certificate. There is no need to submit a medical certificate confirming the delivery (birth).

5. You have the right to bury your baby (his body or remains), regardless of when the pregnancy ends. The hospital then issues a death certificate. This document is needed at the cemetery to bury the child.

6. You are entitled to a funeral grant – regardless of when your pregnancy ends. Documents confirming the right to benefits and a death certificate should be presented to ZUS. If a death certificate has not been drawn up (the child was born still), a birth certificate is presented with a note on the stillbirth.

7. You have the right to information in hospital.

8. Like any patient, you have the right to obtain medical records.

Based on the portal www. poronienie.pl

Recommendations of the Polish Gynecological Society regarding the management of couples who have experienced two or more miscarriages.

1. Genetic research

Both parents should undergo a peripheral blood karyotype. This examination is considered essential. It should be extended to include a genetic consultation, taking into account, if necessary, family chromosomal tests, prognosis for the next pregnancy and indications for prenatal diagnosis. Actions should be taken to ensure that patients with recurrent miscarriages undergo cytogenetic examination of the embryo or chorion in case of failure of the next pregnancy.

2. Assessment of genital anatomy

Ultrasound evaluation of the uterus is one of the basic tests in women with recurrent miscarriages. Examination of the uterus using three-dimensional ultrasound is particularly promising. The frequency of uterine defects as the causes of recurrent miscarriages is estimated from 1,8 to 37,6%. If the ultrasound examination suggests a uterine defect, hysterosalpingography is appropriate. In the case of an abnormal hysterosalpingogram, diagnostics should be extended to include hysteroscopy, and in some cases also to laparoscopy.

3. Immunological research

Autoimmune factors

Antiphospholipid antibodies, i.e. lupus anticoagulant and / or anti-cardiolipin IgG and / or IgM antibodies should be determined in all women with recurrent miscarriages. Primary antiphospholipid syndrome is the presence of antiphospholipid antibodies and pregnancy failure or thrombosis. Pregnancy failures include: three or more consecutive miscarriages before 10 weeks gestation, one or more morphologically normal fetal deaths after 20 weeks gestation, one or more deaths before 34 weeks gestation, births due to severe pre-eclampsia, eclampsia or placental insufficiency . Antiphospholipid antibodies are present in 15 percent. women with recurrent miscarriages, which is quite a significant percentage compared to women with low obstetric risk, in whom the prevalence of antiphospholipid antibodies is less than 2%. Biochemical markers of primary antiphospholipid syndrome are two positive tests performed at least 6 weeks apart for a lupus anticoagulant or anti-cardiolipin antibodies in the range of IgG and / or IgM present in moderate or high titers. The mean titers are above 20 GPL or MPL units, while the titers above 80 GPL or MPL units are considered high.

Alloimmune factors

Women who have experienced several, i.e. four or more consecutive, unexplained miscarriages may be offered the following tests:

– lymphocytotoxic test

– assessment of the percentage of lymphocyte subpopulations, including NK cells

– assessment of HLA class I and II antigens in both partners, and in case of abnormal results, consider immunotherapy.

However, the patient should be presented with the current trends that do not confirm the effectiveness of this type of treatment. A review of 18 randomized, controlled trials showed that the use of various forms of immunotherapy, including immunization with donor or partner lymphocytes and intravenous immunoglobulin administration in women with unexplained recurrent miscarriages, did not significantly prevent subsequent miscarriages. Moreover, there are voices that immunotherapy should no longer be offered to women with unexplained recurrent miscarriages and routine testing for HLA and anti-antibodies should be abandoned.

4. Hormonal research

Routine assessment of progesterone concentration in the second phase of the cycle, similarly to microscopic examination of the uterine mucosa, is not obligatory in women with recurrent miscarriages. There is no question that corpus luteum insufficiency and low progesterone production can prevent implantation or disrupt the early development of pregnancy.

However, there are no reliable methods that would allow the diagnosis of corpus luteum failure in early pregnancy. Microscopic evaluation of the endometrium should be reserved for women with suspected endometrial receptivity disorder. For the information obtained to be reliable, the endometrium should be collected in the so-called implantation window, i.e. between the 7th and 9th day after ovulation.

5. Assessment of the infectious factor

Screening and treatment of bacterial vaginosis and Chlamydia trachomatis infection in early pregnancy in women who previously experienced second-trimester loss or preterm delivery may reduce the risk of these complications. On the other hand, routine tests for toxoplasmosis, rubella, cytomegalovirus and herpes virus are not helpful in the diagnostic and therapeutic process in women with recurrent miscarriages.

6. Testing for congenital thrombophilia

All women with recurrent miscarriage should be interviewed for thrombophilia. It includes the occurrence of thromboembolism, stroke, infarction, venous thrombosis and coronary artery disease in both the patient and her first degree relatives. A positive interview requires testing for the factor V Leiden mutation, prothrombin gene mutation, antithrombin concentration as well as protein C and protein S levels.

The Leiden mutation test can be found in the Medonet Market offer – it is a mail-order diagnosis of blood coagulation related to the Leiden mutation in the F5 gene.