Complete blood count during pregnancy: does the test show fertilization?

When should you take a β-hCG test?

For women:

early diagnosis of pregnancy; prenatal screening of fetal development pathologies; amenorrhea; diagnosis and control of treatment of trophoblastic pathologies; dynamics of chronic placental insufficiency; suspicion of threatened spontaneous abortion or frozen pregnancy; suspicion of ectopic attachment of the embryo; monitoring the course of pregnancy over time; control over the implementation of artificial abortion. For men:

differential diagnosis of testicular tumors.

Interpretation of a general blood test during pregnancy

A general clinical blood test reveals several indicators. They are used to judge the state of internal organs and systems.

• Hemoglobin (HB). This is a protein found in red blood cells. It is necessary to add oxygen to the alveoli of the lungs and transport it to organs and tissues. When oxygen is released from hemoglobin, carbon dioxide is added and carried back to the lungs. This is how tissue respiration occurs.
• Platelets (PLT). Blood plates that prevent bleeding and perform immune functions. If damage occurs in a vessel, platelets, together with clotting factors, form a thrombus that covers the site of damage.
• White blood cells (WBS). Cells of the immune system that protect the body from viral, infectious, and parasitic agents. They absorb pathogenic microorganisms or release a mediator that promotes its destruction. In a detailed analysis, the number of myelocytes, metamyelocytes, lymphocytes, monocytes, eosinophils, and basophils is calculated. Read more about basophils during pregnancy and eosinophils during pregnancy.
• Red blood cells (RBC). Red blood cells that carry hemoglobin and oxygen. If their number is reduced, this means that the pregnant woman develops hypoxia (oxygen starvation), which negatively affects her and the fetus. More about red blood cells in the blood during pregnancy.
• Erythrocyte sedimentation rate. This is a test that reflects the protein levels in plasma. If the number increases, this indicates an inflammatory process in the body.

A healthy woman’s indicators are not always within the normal range. There may be a slight deviation, which returns to normal over time. A pathological process is indicated when the indicator is changed by several units or more.

General blood test during pregnancy: norm in the table

After taking a general blood test during early pregnancy, the woman or the attending physician is given a form on which the numbers of indicators are written. Each of them has its own norm, depending on the trimester of pregnancy.

If the general blood test indicator during pregnancy in the 3rd trimester is significantly changed, additional diagnostic tests are prescribed to find out the cause of the condition.

Poor general blood test during pregnancy

A poor clinical study is judged if any of the parameters are changed up or down by a large number of units.

• If the amount of hemoglobin and red blood cells is reduced, this indicates the onset of hypoxia, oxygen starvation of organs and tissues. This is dangerous for a pregnant woman; insufficient oxygen is transferred to the placenta. With an excessively reduced rate and fetal hypoxia, a decrease in the growth and formation of internal organs is possible.
• If the platelet count is sharply reduced, this indicates the possibility of bleeding, which occurs even with minor damage. As the platelet count increases, the risk of arterial thrombosis increases. This will lead to blockage, which causes tissue necrosis (death).
• If white blood cells are excessively elevated, this is dangerous for the fetus, since the immune system considers it foreign to the mother's body. This condition leads to rejection of the embryo. If the white blood cell count is excessively low, the woman's immune function is not working properly. Possibly the addition of infectious and viral agents that penetrate the placenta and harm the fetus.
• If the ESR number drops below 10 mm/hour. This indicates an increased concentration of red blood cells in the blood. A decrease in the indicator indicates the formation of an inflammatory process in the body.

Any of the above conditions can be eliminated with the help of medical and traditional therapy. It is important to identify it in time, so pregnant women periodically undergo a general blood test.

General blood test for frozen pregnancy

If a woman has a frozen pregnancy, the immune system is activated to eliminate the fetus from the mother's body. Therefore, the number of leukocytes increases sharply. At the same time, the ESR increases, which indicates an inflammatory process occurring in the uterus and birth canal.

A pregnant woman should take a clinical blood test regularly. This is how the doctor monitors the condition of internal organs and systems. If deviations of any indicator are determined, testing is repeated. Additionally, other diagnostic tests are prescribed to determine the cause of the disorder.

Ekaterina Belikova, laboratory diagnostics doctor, especially for Mirmam.pro

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Detailed description of the study

HCG is synthesized by placental cells during pregnancy. It consists of two subunits: α and β. The first is contained in the hormones of TSH, FSH and LH, the second is unique, so a blood test for pregnancy is carried out specifically on it. A positive test result can be obtained 10–11 days after conception.

Unlike pregnancy tests from pharmacies, electrochemiluminescent immunoassay testing allows you to detect pregnancy even before the delay. This is due to the fact that the amount of the hormone in the blood increases faster than in the urine. The synthesis of hCG in the body begins on the first day of implantation of the fertilized egg and continues throughout pregnancy. Until weeks 7-11, the concentration of the hormone doubles every day, and then begins to gradually decrease.

Properties of hCG:

supports the activity of the corpus luteum in the first trimester; triggers the production of estrogen and progesterone to maintain pregnancy; stimulates Leydig cells that produce testosterone in the male fetus. The hCG test is also used for a comprehensive study to assess the risk of abnormalities in fetal development in combination with tests for free estriol and alpha-fetoprotein.

Changes in coagulogram and clinical blood test parameters

Changes in the coagulogram of a pregnant woman are a natural physiological process associated with the appearance of the uteroplacental circulation. It is due to the fact that the pregnant woman’s body prepares for an increase in blood volume during pregnancy and for possible blood loss during childbirth.

During normal pregnancy, the activity of the blood coagulation system increases. This means that already in the 3rd month of pregnancy, fibrinogen increases, which reaches its maximum values ​​​​on the eve of childbirth. Therefore, gynecologists reasonably recommend monitoring this indicator during pregnancy (once per trimester, if there are deviations in these indicators, more often, once a week).

Simultaneously with the increase in fibrinogen, the activity of the internal blood coagulation mechanism also increases, while the analysis shows a shortening of the activated partial thromboplastin time (aPTT). Other parts of the blood coagulation system, such as the coagulation blocker antithrombin III, also change during pregnancy. But as pregnancy progresses, there is a gradual decrease in the activity of this indicator.

But lupus anticoagulant should not be produced normally in a pregnant woman.

Pregnancy also affects the results of a general blood test. Indicators such as hemoglobin and hematocrit may decrease in the second half of pregnancy, and leukocytes, on the contrary, may increase.

INVASIVE PRENATAL TESTING

How can I get information about the effectiveness and safety of a particular procedure? The most common option is to read reviews on the Internet or ask your friends.

However, by consulting with non-specialists, you risk receiving false information. The safest thing to do would be to contact your doctor, consult with him and find out whether this procedure is right for you, whether you have indications for invasive diagnostics and, specifically, amniocentesis. This method helps to learn about more than 200 types of abnormalities that arise due to genetic mutations.

There are few contraindications for amniocentesis and they are all dictated by safety considerations for maintaining pregnancy and fetal health. The main contraindications include:

• threat of miscarriage and placental abruption;
• feverish condition in a pregnant woman;
• acute infectious processes of any localization or exacerbation of chronic infection;
• large myomatous nodes.

Based on the results of the study, we can assume the possibility of developing a number of defects, including those incompatible with life. If no abnormalities are detected, the result of amniocentesis can reassure the woman and show that the child will not have serious disorders and is ready for a full life.

Violations identified by the procedure

Amniocentesis does not detect all congenital pathologies, but it can detect a number of serious chromosomal abnormalities and genetic diseases.

Chromosomal diseases that are detected by amniocentesis with an accuracy of more than 99% include:

• Down syndrome (extra 21st chromosome) is a disease in which there are deviations in mental development, malformations of internal organs and some features of appearance.
• Patau syndrome (trisomy 13 chromosome) is a pathology accompanied by numerous external abnormalities, malformations of the brain and face, and disorders of the central nervous system. Life expectancy during a live birth is most often several days.
• Edwards syndrome (trisomy 18), like other CAs, is accompanied by internal and external anomalies, mental retardation, heart defects are common, life expectancy is on average several months, in rare cases several years.
• Turner syndrome (there is only one sex X chromosome). Only women suffer from this disease. As a rule, people with such an anomaly lead a full life, have normal intellectual development, but they may have malformations of internal organs, infertility and some external features, such as short stature.
• Klinefelter syndrome (1 or 2 extra X chromosomes in a man, total number of chromosomes 47 or 48). The syndrome, characteristic only for men, is usually detected only during puberty. Patients have long limbs and a high waist, sparse facial and body hair, gynecomastia (enlarged mammary glands), gradual atrophy of the testicles, and delayed puberty. Those suffering from this syndrome are in most cases infertile.

After amniocentesis is performed and material for research is obtained, it is analyzed using one of these methods:

Fetal cell karyotype analysis (cytogenetic analysis)

This is a cytogenetic study through which sets of human chromosomes are studied (the so-called karyotype). The specialist draws up a map of chromosomes, arranging them in pairs. The technique allows you to identify changes in the number of chromosomes, their structure, violations of the order of chromosomes (deletions, duplications, inversions, translocations) and diagnose certain chromosomal diseases.

Karyotyping can detect abnormalities such as Down syndrome, Patau syndrome, Turner syndrome, Edwards syndrome, and Klinefelter syndrome, as well as X-chromosome polysomy.

Unfortunately, karyotyping only detects aneuploidies (numerical chromosome abnormalities) and fairly large structural abnormalities, missing microdeletion and microduplication abnormalities that cause a wide range of other diseases. With this test, there is approximately a 1% chance of detecting isolated placental mosaicism. This is a rare deviation in which some placental cells have a normal chromosome complement, while other cells have an abnormal structure. The fetal karyotype itself is normal. There is also a risk of diagnostic errors due to the subjectivity and professionalism of the specialist.

Standard karyotyping requires additional time to bring the resulting cells to the desired state. The duration of cell cultivation is usually 72 hours, and only after this can they be analyzed.

Chromosomal microarray analysis (CMA)

This method will be available after any of the invasive diagnostic options. The study involves processing the material with computer programs, which makes it possible not only to determine the chromosome set of the fetus, but also to diagnose disorders that are not determined by karyotyping. CMA is able to detect 1000 times smaller chromosome breaks than classical cytogenetic analysis. Another significant advantage of CMA is the rapid receipt of results (about four working days).

CMA allows the diagnosis of all known microdeletion syndromes and some syndromes associated with autosomal dominant diseases. When performing the study, pathogenic deletions (disappearance of chromosome sections), duplications (appearance of additional copies of genetic material), areas with loss of heterozygosity, which are important in imprinting diseases, consanguineous marriages, and autosomal recessive diseases, can be identified.

Among prenatal invasive tests, micromatrix has the highest information content and accuracy (more than 99%).

Despite all the advantages of CMA, there is another segment of diseases that this analysis, like karyotyping, cannot identify. These are monogenic pathologies, the presence of which is tested only if there are special indications. With these diseases, the chromosome set of the fetus is completely normal, but there is a mutation of a specific gene responsible for the development of the disease. Monogenic diseases include:

• cystic fibrosis (cystic fibrosis).
• Tay-Sachs disease: a rare inherited disease that affects the central nervous system.
• Muscular dystrophy: progressive weakness and degeneration of muscle tissue.
• Sickle cell anemia: an inherited disorder of the hemoglobin protein.
• Hemophilia: an inherited blood clotting disorder.

Diagnosis for monogenic diseases is carried out only if it is known what specific disease risk the child has and what mutation needs to be looked for. There may be a known disease in the family of the unborn child, or when planning a pregnancy, screening for hereditary diseases is carried out, with the help of which it is revealed which mutations the future parents are carriers of, and, therefore, what genetic diseases the child may have.

In rare cases, amniotic fluid analysis is performed to assess the intrauterine condition of the fetus and other parameters, in addition to the presence of genetic pathology.

Biochemical analysis is carried out if there is a suspicion of hemolytic disease of the fetus during Rh-conflict pregnancy, to diagnose possible congenital diseases, as well as to assess the maturity of the fetus. Amniotic fluid can be used to analyze:

AFP (alpha fetoprotein)

is a protein that is formed during fetal development. Its amount in amniotic fluid varies depending on the duration of pregnancy. Exceeding the standard values ​​occurs with malformations of the fetal nervous system, with the threat of intrauterine fetal death, and with some congenital kidney diseases. A decrease in the concentration of alpha-fetoprotein in amniotic fluid can be recorded in Down syndrome, if the pregnant woman has diabetes mellitus.

Bilirubin

is a substance that is formed in the human body during the destruction of red blood cells. Increased bilirubin can negatively affect the health of the unborn child and can also indicate various diseases. For example, cholecystitis, viral hepatitis, hemolytic anemia, etc. With hemolytic anemia, if it is not treated prematurely, there may be a risk of premature birth or stillbirth.

Glucose

– carbohydrate, which is an essential component of metabolism in the human body. Normally, the glucose concentration in amniotic fluid is less than 2.3 mmol/l. An increase in its quantity indicates a pathology of the fetal pancreas, as well as a possible risk of developing severe hemolytic disease in the child. A decrease in glucose concentration is observed during intrauterine infection and in patients with leakage of amniotic fluid, as well as during postterm pregnancy.

Immunological analysis

Among the indicators characterizing the state of the body's immune defense, pro-inflammatory cytokines, which act as mediators of immune reactions, are of great importance. Analysis of the content of cytokines in amniotic fluid is of great diagnostic importance. The cytokine system includes interferons (IFNs), tumor necrosis factor (TNF) and interleukins (ILs). These are low molecular weight glycoproteins that regulate the duration and strength of immune reactions, as well as inflammatory reactions.

Hormonal analysis

In recent years, the study of amniotic fluid hormones has increasingly become the subject of scientific research, providing information on the degree of maturity and development of the fetus, and is also of practical importance for resolving the issue of timing of labor induction in pregnant women, a group at risk of developing intrauterine infections.

Thus, the functional state of the placenta is determined, in particular, by the synthesis of human chorionic gonadotropin (hCG) and placental lactogen in it. Of all the hormones involved in changing the endocrine balance of the body and largely determining the characteristics of the course of pregnancy and childbirth, the greatest importance should be given to the content of cortisol, estradiol, estriol, progesterone and placental lactogen in the amniotic fluid during pregnancy and childbirth.