Coagulogram norms during pregnancy by trimester and interpretation of analysis indicators. Coagulogram: essence and indications for the study, parameters, how and where to take it What does a coagulogram analysis show during pregnancy

As soon as a woman becomes pregnant, her whole life becomes different. The body is rebuilt in preparation for the growth of the fetus, physiology changes, completely new views on life appear, and the emotional state changes.

But another important point is registration in the antenatal clinic and endless testing, including a coagulogram, which significantly complicates life during pregnancy.

What kind of analysis is this, how often it needs to be done and why – we will consider below.

What is a coagulogram?

A coagulogram (clotting test) is a common blood test that helps examine its ability to clot: whether there are any disorders in the form of increased or decreased coagulation.

It is done without fail, since with its help the hemostasis system is examined, and the tendency of the expectant mother’s body to blood clots and bleeding, which affects the pathological development of the child, difficult or premature births, miscarriages, and other disorders, is also determined. Providing the results of the hemostatic system in graphical form is also called a hemostasiogram.

When analyzing a coagulogram, the main and additional indicators of coagulation are checked (presented in the table below).

Coagulogram

Kinds	Indicators

1. Main
	2. Prothrombin, including INO
	3. APTT
	4. Thrombin time

2. Advanced	Basic indicators
	+ additional
	5. Antithrombin III (AT3) index
	6. D-dimer
	7. Lupus anticoagulant

Violations when an extended coagulogram is prescribed

Coagulogram norms during pregnancy

A coagulation test is an important diagnostic test for normal pregnancy. The normal coagulogram indicators for a pregnant woman are presented in the table below.

P/n Coagulogram norm during pregnancy table

	Coagulogram indicators	Value for pregnant women by trimester
1	Fibrinogen (factor I)	norm	1st trimester
		4-5 g/l	2nd trimester
		6 g/l	3rd trimester
	Protein in the first trimester of a pregnant woman is the same as the norm, and after that it increases
2	Thrombin time	11-18 seconds	1st, 2nd and 3rd trimester
	If the thrombin time is reduced, then with damage to blood vessels or organs it can lead to metrorrhagia, and if it is increased, then to liver dysfunction.
3	Activated partial thromboplastin time (APTT)	17-20 sec
	In a pregnant woman, the value is higher than the norm
4	Prothrombin	78-142 %	throughout pregnancy
	An increase in value leads to placental abruption
5	Prothrombin time	up to 18 seconds	throughout pregnancy
	The value during pregnancy is normal. If there are significant differences, then you urgently need to undergo an examination and eliminate the cause of its change
6	Lupus anticoagulant	no antibodies
	The number of antibodies should show a zero value, otherwise this indicates an autoimmune complication of pregnancy
7		78-130 units	1st trimester
		85-135 units	2nd trimester
		90-140 units	3rd trimester
	An increase in the value indicates that venous thrombosis may form.
8	Antithrombin III	75-125%	throughout pregnancy
	If antithrombin 3 is reduced, this warns of possible blood thickening and the creation of blood clots, and if it is increased, it warns of bleeding
9	D-dimer	0-525 ng/ml	1st trimester
		438-1200 ng/ml	2nd trimester
		888-2085 ng/ml	3rd trimester
	Indicates the formation of blood clots: a slight increase is not scary for pregnant women, but its sharp increase can cause kidney diseases, diabetes and other complications.

In the coagulogram table, normal values of indicators, based on the results of a laboratory analysis of coagulation, will give the result of isocoagulation.

Isocoagulation is a definition that means that the state of the coagulation system is normal, and therefore pregnancy proceeds normally, so there is nothing to worry about.

If gestosis or another disorder of pregnancy is confirmed, then coagulation occurs with disturbances, which means that treatment must be started immediately, or intravascular disseminated coagulation syndrome (DIC syndrome) may develop.

This syndrome occurs in stages.

Hypercoagulation– Stage 1, during which numerous blood clots occur that interfere with the normal vascular pathway between mother and fetus.
Hypocoagulation– Stage 2, when blood clots are destroyed by weakening the factors responsible for coagulation.
Acoagulation– the last stage, during which blood incoagulability occurs and uterine bleeding develops, which is life-threatening for the mother and child.

But remember, even if the test results are far from normal, but the coagulogram was done on time, and treatment is carried out promptly, then many risks can be eliminated.

The need and frequency of testing for coagulation during pregnancy

For pregnant women, a coagulogram is an extremely important analysis. With its help, the balance of the coagulation and anticoagulation systems is monitored.

The absence of such a balance carries, as mentioned above, consequences that threaten the health of the expectant mother and fetus.
An imbalance towards the anticoagulation system can cause metrorrhagia, placental abruption, blood loss during and after childbirth in a woman in labor, and towards the coagulation system it thickens the blood, forming blood clots. In this case, a child who receives oxygen exclusively from the placenta experiences oxygen starvation, hypoxia develops, brain pathologies may develop, the woman suffers from leg pain and the development of blood clots, and this can also cause a heart attack, stroke or miscarriage.

The test procedure is as follows: before taking blood, it is better to fast, that is, take the test on an empty stomach. Blood is taken from a vein on the bend of the elbow, and the result of the hemostasiogram is deciphered by your attending physician.

If the indicators are normal, the diagnosis is carried out three times as planned:

During the registration of a pregnant woman (usually the 1st trimester),
In the second trimester,
A week or two before giving birth, which is especially important for women who are preparing to give birth by cesarean section.

In case of complications or abnormal pregnancy, homeostasis is checked much more often in order to respond adequately and prescribe effective treatment.

The normal indicators for a woman during this period, due to changes in physiology, are somewhat different from the indicators before conception, since the female body sets up another blood circulation through the utero-placental-fetal blood flow (insuring itself from significant blood loss). Therefore, only your registered doctor can diagnose the coagulogram results.

Hemostasiogram of indicators during pregnancy and interpretation of the results

What do clotting indicators determine:

- this is a special protein, which is the main component of a blood clot, produced in a healthy person by the liver and it is distributed by blood movement through all blood vessels. If there is a damaged area in the vessel, then this protein turns into insoluble fibrin, which becomes the main component of the blood clot that clogs the damaged vessel, thereby stopping the flow of fluid from it. Such a thrombus, with a normal number of elements, will exist at the site of the lesion until the wound is completely healed.

Stop bleeding

If there is a lack of factors 1 and 2, it can cause metrorrhagia, and if they are in excess, unhealthy blood clots will appear - those that break off and wander through the vessels, creating interference with the free vascular path.

The fibrinogen rate is measured in mg/dL or g/L, with g/L leaving mg/dL*0.555/100. Towards the end of the period before childbirth, the value increases slightly. And its reduced value should not fall below 0.5 g/l on the coagulogram, as this is very dangerous for health.

An increase in protein may be the cause:

Inflammatory diseases
Pathologies of protein metabolism,
Surgical intervention before taking diagnostic tests,
Skin lesions due to high temperature (burn),
Increased amount of estrogen,
A small number of hormones that the thyroid gland should produce.

A critical decrease in fibrinogen (below 0.5 g/l) is dangerous:

Development of DIC syndrome,
Lack of vitamins C and B12,
Failure of the heart or liver,
Postpartum complications,
Acute promyelocytic leukemia.

It requires thrombolytic treatment.

Thrombin time– this is the period during which plasma combines with thrombin to create a blood clot.

APTT– the time period for creating a blood clot, which is used to check how well the coagulation system works and the sufficiency of plasma factors in the blood.

A lengthening of the time period indicates that the pregnant woman has:

DIC syndrome stage 2 or 3,
Hemophilia A, B, C,
Accelerated production of antibodies to phospholipids.

A shortened interval may be due to:

Stage 1 DIC syndrome,
Trombozov,
Injury to a vein during sample collection.

Prothrombin(factor 2) a complex protein, one of the main homeostasis factors that determine the quality of blood clotting, which is produced by the liver with the help of vitamin K.

According to the coagulogram, its increase is dangerous:

Formation of blood clots,
Damage to the heart muscle
Thromboembolic syndrome.

Formation of blood clots

A decrease in prothrombin indicates:

Low number of fibrinogens in the blood and the development of hypofibrinogenemia,
Low vitamin K content in children manifests itself as hemorrhagic diathesis,
Lack of prothrombin causing metrorrhagia.

Prothrombin also increases and decreases due to pregnant women taking medications that slow down or enhance the effects of coumarin.

INR(prothrombin time)– this is the period of time when a thrombin clot is created when Ca and tissue factor enter the blood.

Lupus anticoagulant– these are antiphospholipid antibodies Ig class M, G, which in the case of pathologies of the immune system are produced to disrupt the impermeability of platelet membranes. Its presence is dangerous due to complications and miscarriage.

Soluble fibrin monomer complex (SFMC)- this is intermediate consumption, which appears as a result of the breakdown of fibrin lumps, which are very difficult to determine due to their rapid removal from plasma. It is allowed to increase the Rfmk norm in the 2nd trimester and until the end of the term.

Antithrombin III is a protein whose main task is to prevent hemostasis and the formation of clots.

D-dimer– This is the period of thrombus formation and fibrin breakdown. This number gradually increases during pregnancy.

conclusions

A hemostasiogram is of great importance, both for the life and health of a pregnant woman and her unborn child. And if the coagulogram is normal, then there is nothing to worry about, therefore there is no danger to the health of the mother and fetus. But if the indicators are outside the normal range, then you need to contact your doctor for advice as soon as possible.

The main thing is not to panic, but to undergo all the examinations that your doctor prescribes, so that, if necessary, you can adjust the treatment to obtain good results.

A coagulogram is a study of the blood coagulation system. A coagulogram allows you to identify the characteristics of coagulation disorders in a pregnant woman and some complications of pregnancy and, therefore, carry out the correct treatment.

During the normal course of pregnancy, the activity of the blood coagulation system as a whole increases. This is a natural process associated with the appearance of the uteroplacental circulation. It is due to the fact that the pregnant woman’s body is preparing for an increase in blood volume during pregnancy and for possible blood loss during childbirth.

A coagulogram should be taken once every trimester, and if there are deviations in hemostasis indicators (the set of components of blood vessels and blood, the interaction of which ensures the maintenance of the integrity of the vascular wall and stops bleeding when the vessels are damaged) - more often, as prescribed by a doctor.

Blood for analysis is taken from a vein in the morning on an empty stomach.

Main indicators of coagulogram

Fibrinogen- a protein, a precursor of fibrin, which forms the basis of the clot during blood clotting. Normal values are 2.0-4.0 g/l. Fibrinogen is a sensitive indicator of the presence of inflammation and necrosis (death) of tissue, the main plasma protein that affects the value of ESR (erythrocyte sedimentation rate). It increases with increasing fibrinogen concentration. During pregnancy, starting from the end of the first trimester, there is a natural increase in plasma fibrinogen content and reaches maximum values (up to 6 g/l) on the eve of childbirth. This is due to the appearance of an additional circulation - the uteroplacental.

APTT- activated partial thromboplastin time, normal - 24-35 s. This is the clotting time of the blood, depending on the presence of clotting factors. The determination of APTT, along with other indicators, is used in the diagnosis of disseminated intravascular coagulation (DIC), which is discussed below. In pregnant women, a shortening of the aPTT to 17-20 s is observed due to an increase in the amount of fibrinogen.

Lupus anticoagulant— should not normally be produced by a pregnant woman. This is a group of antibodies (IgM and IgG) to the outer membrane of platelets. The presence of these antibodies is accompanied by an increase in aPTT. These antibodies appear in autoimmune diseases (when the work of the immune system is directed against its own organs), in the pathology of pregnancy (preeclampsia - a complication that worsens the condition of the mother and fetus and is manifested by increased blood pressure, the appearance of edema, and protein in the urine). Such patients are characterized by thrombosis of arteries and veins. Pregnancy against the background of such pathology is often complicated by spontaneous abortion, placental infarction, and fetal death.

Thrombin time (TV)- normal - 11-18 s. This is the time of the last stage of blood coagulation: the formation of fibrin from fibrinogen under the influence of thrombin. Considering that during pregnancy the fibrinogen content increases, therefore, the thrombin time lengthens, but remains within the specified limits. The determination of TV is used to identify defects in the production of fibrinogen (for example, fibrinogen may increase in liver pathology) and to assess the anticoagulant activity of the blood.

Prothrombin- normal values - 78-142%. This indicator is determined as a percentage, since it allows one to determine the activity of the prothrombin complex of the patient’s plasma in comparison with the measured prothrombin time of the control plasma. One of the most important indicators of a coagulogram, characterizing the state of the blood coagulation system, is the time of the second stage of coagulation - the formation of thrombin from prothrombin. An increase in this indicator in pregnant women may occur due to premature placental abruption.

How does the blood coagulation system work?
The blood clotting process consists of several stages. At the first stage, when there is mechanical or chemical damage to the wall of a blood vessel, a special substance is released - thromboplastin, which triggers coagulation reactions. The second stage is the activation of coagulation factors - special proteins that are normally always present in the blood, which ensure the formation of a blood clot at the site of damage to the vascular wall. The third stage is the activation by thrombin (a natural component of the blood coagulation system, which is formed in the body from prothrombin) of the inactive fibrinogen protein, converting it into active fibrin, which forms the basis of the clot. Platelets and other blood cells become entangled in fibrin networks; the platelets contract the clot, compress it and form a mature thrombus, which closes the defect in the vascular wall.
In contrast to the coagulation system, the body has an anticoagulant system. The coordinated work of these systems allows you to maintain the normal state of the blood.

Antithrombin III- normal values - 71-115%. This is a protein of the anticoagulation system, a thrombin inhibitor. It has an inhibitory effect on blood clotting processes. The amount of antithrombin III is determined by inhibition (binding of thrombin in the control sample). Its decrease can lead to thrombosis. For expectant mothers, determining this indicator is important when using anticoagulants - drugs that reduce blood clotting. These drugs are used during pregnancy when blood clotting increases, since this condition leads to pregnancy, the formation of placental insufficiency, etc. A decrease in the level of antithrombin III by 50% of normal indicates a risk of thrombosis.

D-dimer- normal - less than 248 ng/ml. This is an indicator of thrombus formation (the process of clot formation, which consists of three successive stages described above) and fibrinolysis (dissolution of fibrin). The determination of this indicator is important in clinical practice for the diagnosis of thrombosis. In pregnant women, starting from early pregnancy, the level of D-dimer in the blood gradually increases. By the end of pregnancy, its values can be 3-4 times higher than the initial level - this is a variant of the norm. Significantly higher levels of D-dimer are observed in women with complicated pregnancy, as well as in pregnant women suffering from diabetes and kidney disease.

Platelets- these are the formed elements of blood involved in ensuring hemostasis. Platelets are formed in the bone marrow. The norm of platelets is 150-400 thousand/µl. A moderate decrease in platelet count (up to 130 thousand/μl) can sometimes be observed in healthy pregnant women. Thrombocytopenia—a significant decrease in platelet count—may result from decreased platelet production, increased platelet destruction, or increased platelet consumption. Platelet production decreases with insufficient nutrition. Platelet consumption increases in DBS syndrome.

A coagulogram should be taken once every trimester, and if there are deviations in hemostasis indicators, more often, as prescribed by the doctor.

Blood clotting disorders in pregnant women. Complications and consequences

The balance between the coagulation and anticoagulation systems is maintained through the interaction of platelets, coagulation factors and the process of fibrinolysis. A disorder affecting any of these links can cause serious pregnancy complications. Among these complications, the most dangerous is DIC syndrome (disseminated intravascular coagulation). This syndrome develops due to activation of the coagulation system, on the one hand, and the fibrinolysis system, on the other. DIC syndrome in pregnant women can be caused by various reasons. Among them:

premature - abruption of a normally located placenta before the birth of the child. In 80% of cases, this disease is accompanied by bleeding from the genital tract, sometimes a hematoma forms behind the placenta. Bleeding is associated with a decrease in plasma concentrations of coagulation factors, fibrinogen and platelets;
Amniotic fluid embolism is a rare but dangerous complication that develops during complicated labor and is caused by the entry of amniotic fluid into the mother’s bloodstream and pulmonary vessels, which leads to acute respiratory failure and shock. DIC syndrome develops as a result of massive entry into the bloodstream of tissue thromboplastin, a substance that triggers the blood clotting process;
endometritis - inflammation of the inner lining of the uterus - which develops after childbirth, can be complicated by the fulminant form of DIC syndrome.

One of the reasons for termination of pregnancy at various stages is antiphospholipid syndrome (APS). APS is a complex of symptoms characterized by venous and arterial thrombosis. Pregnant women are at increased risk of pregnancy and spontaneous abortion due to a violation of the increase in the number of placental vessels with development - a violation of the basic functions of the maternal placenta, leading to serious disturbances in the intrauterine development of the fetus, as well as due to vascular changes. To make a diagnosis of APS, in addition to increased thrombosis, antibodies to phospholipids (the outer shell of membranes) are determined.

Coagulogram is a blood test that determines the level of its hemostasis (ability to clot). In some medical sources it has a second name “hemostasiogram”. Carrying out this analysis allows us to fully evaluate the work of the coagulation and anticoagulation systems.

If there is a shift in activity towards the coagulation system, an increase in thrombus formation processes is noted in the blood. Formed blood clots can settle in the vessels of the placenta, preventing normal blood flow. Thus, fetoplacental insufficiency may develop, leading to fetal hypoxia.

In addition, in late pregnancy, the load on the venous system increases, resulting in the development of varicose veins of the lower extremities and hemorrhoids. In dilated vessels, the speed of blood flow is reduced and the formation of blood clots is increased. A blood clot formed in a varicose node can easily break away from the walls of the vessel and, passing through the bloodstream, clog a smaller vessel in another part of the body. This is dangerous due to the development of thrombosis of the lower extremities, deep veins of the pelvis, as well as pulmonary embolism (pulmonary embolism).

If the anticoagulant system of the blood is more active, there is a possibility of developing serious bleeding due to insufficient formation of blood clots. This can cause severe bleeding if placenta previa is disturbed, placenta abruption occurs, during natural childbirth or cesarean section. Complications may also occur in the postpartum period, leading to uterine hypotension. This, in turn, can lead to life-threatening blood loss.

At what stage of pregnancy is a coagulogram performed?

The question of how often to take a coagulogram during pregnancy cannot be answered unambiguously. The patient’s examination protocols indicate the need for hemostasiograms to be taken three times throughout the entire pregnancy, once per trimester:

during registration (up to 12 weeks);
at 20 - 24 weeks of pregnancy (duration);
at 32 - 36 weeks of pregnancy (to prepare for delivery).

However, this test scheme is only suitable for those patients who do not have a complicated medical history, pregnancy proceeds without complications, and previous coagulogram results were within normal limits. In all other cases, the timing of the analysis is decided by the attending physician.

Important! Before any surgical intervention (appendectomy, cholecystectomy, cesarean section), donating blood for a coagulogram is mandatory!

Additional coagulation analysis may be prescribed for the following conditions:

smoking during pregnancy;
fetoplacental insufficiency;
fetal hypoxia;
delayed growth and development of the fetus;
varicose veins;
history of infertility and miscarriage;
multiple pregnancy;
disruption of the cardiovascular, urinary and other organ systems.

Rules for taking a coagulogram test during pregnancy

Blood for hemostasiogram analysis is taken from a vein with a syringe. In order for the result to be the most reliable, it is necessary to prepare for a coagulogram test during pregnancy, adhering to such measures as:

Before the procedure, do not eat food for 7-8 hours. Most often, blood donation occurs in the morning, so you must arrive on an empty stomach. In the morning you are allowed to take a couple of sips of water and brush your teeth.
It is advisable to limit yourself from stress and anxiety during any tests.
Avoid increased physical activity for two days preceding the procedure.

Detailed coagulogram during pregnancy: what indicators are included?

There are two types of coagulogram: standard and expanded. As a screening method, a standard type of coagulogram is used, including the following indicators:

APTT (activated partial thromboplastin time). This indicator determines the optimal time for the formation of a blood clot. A decrease in aPTT threatens the development of DIC syndrome (disseminated intravascular coagulation) in the postpartum period; an increase in the indicator means an increased risk of bleeding.
Fibrinogen. It has a protein nature and is produced in the liver. Refers to the main link in thrombus formation. Fibrinogen levels increase slightly before labor. A sharp increase in the indicator is characteristic of the development of an infectious process.
Thrombin time. Shows how long it takes fibrinogen to transform into fibrin, and then fibrin forms a blood clot.
Prothrombin (or prothrombin index, PTI). It is one of the components of blood plasma. Shows how active the plasma prothrombin complex is compared to the plasma prothrombin time. An increase in the level of PTI is typical for.

An extended coagulogram during pregnancy includes additional indicators:

Prothrombin time (or PTT). An indicator showing how many seconds it takes to form thrombin from prothrombin, which is involved in the formation of a blood clot.
Antithrombin III. This is a protein that slows down blood clotting. A decrease in it during pregnancy carries a risk of developing pathological thrombosis, and an increase carries a risk of bleeding.
Platelets. Blood cells responsible for the state of the coagulation system. They are the ones who fill the fibrin networks, forming a blood clot. A slight decrease in platelets during pregnancy is a common occurrence, but significant fluctuations are a sign of pathology (a decrease in their production or, conversely, increased destruction). A significant decrease in the indicator carries the risk of developing DIC syndrome.
INR (international normalized ratio). This is a calculated indicator characterizing the ratio of the patient’s prothrombin time to the total average thrombosed time. An increased INR carries a risk of bleeding, a decreased INR carries a risk of thrombosis. The indicator is often determined to monitor the condition when treating patients with anticoagulants and antiplatelet agents.
D-dimer. One of the main indicators of the thrombus formation procedure. Determining d-dimer in a coagulogram during pregnancy and before conception makes it possible to timely identify the risk of thrombosis and begin timely treatment with anticoagulants.
Lupus anticoagulant. Antibody formation indicator. Normally, it should be absent during pregnancy. Its presence in the blood indicates either the presence of autoimmune diseases or the development of Rh conflict.
RFMC (soluble monomer complexes). An indicator that allows you to assess the massiveness of thrombus formation. During pregnancy, it can be 2-3 times higher than the non-pregnant norm. A significant increase occurs in shock conditions: disseminated intravascular coagulation syndrome, trauma, extensive thrombosis.

Coagulogram during pregnancy: norms and interpretation

Correct interpretation of the results of a coagulogram can only be carried out by the attending physician, who is familiar with the history of pregnancy, history of somatic diseases, results of other tests and medications taken by the patient.

Important! The normal blood coagulogram during pregnancy (especially in the 3rd trimester) is somewhat different from generally accepted norms, since during this period there is a physiological change in some blood parameters.

Coagulogram during pregnancy: interpretation of the results in the table

Index	Meaning

Fibrinogen	up to 14 weeks - 2-4 g/l from 14 to 30 weeks - 4-5 hl after 30 weeks - about 6 hl
Thrombin time
Prothrombin
Antithrombin III
Platelets	150 - 380 thousand/µl
	During treatment with anticoagulants, the indicator should not exceed 2.5
	up to 14 weeks - up to 750 ngml from 14 to 30 weeks - up to 1000 ngml after 30 weeks - up to 1500 ngml
Lupus anticoagulant	absent

Important! Each laboratory may have its own reference values, slightly different from those given in the table.

Poor coagulogram during pregnancy: what are the dangers?

It is very important to consider changes in coagulogram parameters comprehensively, since they are all closely related to each other. An increased coagulogram during pregnancy poses a risk of thrombosis, which can result in:

fetoplacental insufficiency;
fetal hypoxia;
fetal growth restriction;
deep vein thrombosis of the lower extremities and pelvis;
TELA;
thrombosis of mesenteric vessels;
DIC syndrome in the postpartum period;
renal artery thrombosis with subsequent renal failure;
placental infarction;
spontaneous abortion in early pregnancy.

The main consequence of a coagulogram in a blood test during pregnancy, in which the blood clots slowly, is a high risk of bleeding during childbirth and the postpartum period. Not only is this a life-threatening situation, but it may also require removal of the uterus to stop bleeding.

Among other things, the value of the lupus anticoagulant is very important, the appearance of which in the hemostasiogram is typical for:

rheumatoid disease;
systemic lupus erythematosus;
severe gestosis;
placental infarction and intrauterine fetal death;
Rhesus conflict.

A hemostasiogram is a very important study, with the help of which most abnormalities in the blood coagulation system are determined. Timely conduct and monitoring of the results of a coagulogram during pregnancy helps to detect pathological changes in time and prevent undesirable consequences.

Anastasia Vinarskaya, obstetrician-gynecologist, especially for the site

Useful video

During pregnancy, a woman’s body is constantly changing, all organs and systems adapt to carrying a child and his birth. Blood clotting is one of its most dynamic indicators during all 9 months. Towards the end of the term it increases, preventing blood loss during childbirth. A coagulogram during pregnancy allows you to timely identify the risk of blood clots and some other conditions that complicate the process of bearing a child and put it at risk.

Such an examination must be completed three times in 9 months, that is, every trimester. If there are indications and deviations in the results, a coagulogram may be prescribed more often and with expanded indicators.

Coagulogram is an analysis of blood clotting ability. It shows whether there are violations of hemostasis - the system responsible for ensuring that blood flows through the vessels and clots when they are damaged.

There are two types of bleeding disorders:

Hypocoagulation – low rates of hemostasis, lack of thrombus formation and, as a consequence, large blood losses even with minor vascular damage.
Hypercoagulation – high rates of hemostasis, rapid formation of blood clots with the risk of thrombosis, heart attack and stroke.

During pregnancy, these disorders are dangerous and can lead to miscarriage, premature birth of a child and large blood losses during childbirth. Throughout the entire period, a natural change in clotting indicators occurs, as provided by nature.

Why is a coagulogram needed during pregnancy?

During pregnancy, it is important that blood clotting parameters remain normal. Hypercoagulation can lead to complications during pregnancy. The fetus receives all the necessary nutrients and oxygen through the placenta, which is penetrated by many vessels. If blood clots appear in them, blood circulation is disrupted, and the child develops hypoxia, a deficiency of vitamins, microelements and some other compounds important for development.

As a result, the risk of congenital pathologies increases. Poor circulation in the mother-placenta-fetus system can also lead to miscarriage, fetoplacental insufficiency, severe gestosis and the formation of blood clots in the mother’s vital vessels.

Hypocoagulation during pregnancy occurs against the background of a natural decrease in immunity, which protects the fetus from rejection by the maternal body.

Low coagulability is dangerous during childbirth, as there is a high risk of blood loss incompatible with life. In later stages, such a violation can cause placental abruption. After birth, a child sometimes also experiences hypocoagulation.

How and when is the analysis carried out?

To test blood for clotting, a sample from a vein is needed. It is best to take the test in the morning, since it needs to be done on an empty stomach. At least 8 hours must pass from the last meal to the blood sampling procedure. During this time, only clean water is allowed to drink. You must tell the laboratory assistant about taking medications during the day before the analysis or make an entry on a form with personal data.

Normally, a coagulogram during pregnancy is performed once every trimester. In case of vascular, immune and hepatic disorders, this examination is performed more often. Also, additional procedures may be required for women with a negative Rh factor and with unsatisfactory previous results (after a course of treatment).

Decoding the result and norms of indicators

The coagulogram reflects five main indicators by which deviations in blood clotting are determined:

Fibrinogen. These are the protein molecules that form most of the clot during coagulation. Usually their norm is from 2 to 4 g/l, but during pregnancy the figure can increase to 6 g/l. Every month this protein becomes more and more, the maximum amount is observed at the time of birth.
APTT. The indicator reflects the time period during which the blood has time to clot. The norm for pregnant women is 18-20 s, for others – up to 35 s.
Thrombin time. This is the duration of the last stage of coagulation. In healthy people, the indicator ranges from 11 to 18 s. During pregnancy, it increases slightly due to more fibrinogen, but is within the upper limit of normal.
Prothrombin. One of the blood proteins involved in the formation of clots. The thickness of the blood and the possibility of timely clotting depend on its concentration. The normal indicator should fall in the range from 78 to 142%.
Platelets. These are blood components that are produced by the bone marrow and are involved in the clotting process. The norm is 150-400 thousand/µl, but in pregnant women a reduction to 130 thousand/µl is permissible.

The given data indicate the average norm, but in practice they may be higher or lower than indicated, even during a normal pregnancy. Chronic diseases, taking certain medications, and even dietary habits affect clotting. Therefore, the results must be deciphered by a doctor.

Reasons for deviations from the norm

Depending on which indicator or their combination in the coagulogram deviates from the norm, the doctor may suggest one or another pathological condition or disease:

Fibrinogen. The amount of this protein decreases with toxicosis, liver disease, disseminated intravascular coagulation syndrome, taking anticoagulants, vitamin B12 and/or C deficiency, as well as chronic myeloid leukemia. Increased rates are found in pregnant women with infectious diseases, hypothyroidism, myocardial infarction, stroke, pneumonia, cancer, and those who have undergone surgery or burns.
APTT. A decrease in the indicator is observed in the 1st phase of DIC syndrome, an increase is observed in antiphospholipid syndrome, hemophilia, decreased coagulability and in the last phases of DIC syndrome.
Thrombin time. It increases with changes in the amount of fibrinogen, taking drugs with heparin, liver disease and DIC syndrome. A decrease may indicate the onset of DIC syndrome.
Prothrombin. The amount of this protein in the blood may increase in women taking certain medications (for example, corticosteroids), as well as in cases of thrombosis and cancer. A decrease is observed in diseases of the gastrointestinal tract, disseminated intravascular coagulation syndrome, hereditary disorders of the circulatory system, leukemia and taking certain medications.
Platelets. The level of these elements increases during inflammatory processes, anemia, blood loss, cancer, blood pathologies, and also during physical stress. A decrease may indicate infection, systemic lupus erythematosus, thrombocytopenic purpura, enlarged spleen and disseminated intravascular coagulation syndrome.

How do coagulogram data change during pregnancy?

As pregnancy progresses, blood clotting constantly increases, reaching a maximum towards childbirth. From the third month, fibrinogen levels begin to increase. Further, it constantly grows until the end of the term.

In parallel, there is an increase in the activity of the internal blood coagulation mechanism, in the results of the coagulogram this is reflected in a decrease in APTT. During pregnancy, the antithrombin III level decreases, which corresponds to the general trend towards increased coagulation.

Changes in coagulogram data during pregnancy are natural and physiological. They occur due to the appearance of another circle of blood circulation - the uteroplacental. The body increases the volume of circulating blood and its coagulability - these two mechanisms prevent the risk of blood loss during the birth of a child.

Indications for extended coagulogram

In some cases, an extended coagulogram during pregnancy (with additional indicators) is required. Such an examination is indicated if, as a result of the previous analysis, deviations from the norm were observed. It can also be prescribed to pregnant women with diseases accompanied by blood clotting disorders (liver pathologies, heavy menstruation or frequent nosebleeds, thrombosis and thromboembolism).

Analysis like coagulogram It is quite widely known, but is not prescribed during a standard medical examination. Therefore, patients are sometimes surprised by the doctor’s proposal to conduct this study. More often, a blood coagulogram is performed in patients with pathology of the cardiovascular system, as well as before a planned operation or in pregnant women. In the latter case, it is done every trimester without fail.

What is hidden under the mysterious term? Coagulogram (another name for the study is hemostasiogram) is carried out to study the patient's blood clotting. Analysis happens basic And expanded. Typically, a baseline study is ordered first. It helps to understand where in the system the deviation from the norm occurred. And if a pathology is detected, a detailed study is carried out, as a result of which not only qualitative changes are determined, but also quantitative ones.

Main indications for analysis

Planned operations. There is always some risk of bleeding during surgery. Therefore, knowledge about the state of the blood coagulation system is important.
Pregnancy. During this period, changes can occur in the female body, both positive and negative. It is usually carried out once every trimester. If fetoplacental insufficiency is diagnosed or more often.
Vascular disorders (increased thrombus formation,).
Liver diseases.
Autoimmune pathologies.
Violation .
Cardiovascular pathology (,).
When prescribing anticoagulants.
For the correct selection of the dose of acetylsalicylic acid and drugs based on it.
Prescription of contraceptive drugs. In this case, the analysis is done once every 3 months.
. A coagulogram is performed to prevent hemorrhages.

Natural hemostasis system

In a healthy body, a normally functioning system hemostasis– natural protection against excessive blood loss when the integrity of the vascular wall is violated. Many people know about the danger to human health and life, but nature does not create anything in vain: thrombus formation is the very protection against blood loss. Let's try to find out how the natural hemostasis system works.

Blood is constantly in a liquid state. Moreover, this liquid has a certain composition and physical parameters. The body's systems tirelessly maintain this state throughout life. However, various situations occur: for example, as a result of damage to the wall of a vessel, it opens. The first substance that is released in the blood is thromboplastin. It starts the coagulation system: it activates proteins that are normally present in the blood. These proteins form a clot at the site where the integrity of the vessel is damaged. A chain leading to thrombus formation is carried out: from prothrombin thrombin is synthesized, which activates fibrinogen, from which, in turn, is formed fibrin. It is in fibrin, like insects in a spider's web, that platelets get stuck, forming a blood clot. The fibrin clot “patches” the wound in the vessel, and the bleeding stops.

In a healthy body, both systems - coagulation and anticoagulation - are in balance. But there is also a third system - absorbable (). It is this that ensures the dissolution of the blood clot after the integrity of the vessel is restored. Coagulogram indicators allow us to draw a conclusion about the state of all systems.

Basic hemostasiogram parameters

. The most important test of the state of the coagulation system.
, INR (international normalized ratio), PTT (prothrombin time). Usually one of these tests is performed, based on the equipment available in the laboratory. The most universal test is. All of these studies show an extrinsic clotting pathway.
. In the test you can find the abbreviation - APTT.

Additional hemostasiogram parameters

Protein C. An insufficient amount of this parameter leads to thrombosis.
. Like protein C, it is a factor in the anticoagulation system.
. Formed as a result of the destruction of a blood clot.
Plasma tolerance to heparin.
AVR (Activated recalcification time).
(soluble fibrin-monomer complexes).
Plasma recalcification time.

Carrying out a coagulogram during pregnancy

Who, while completely healthy, gets the most research? Undoubtedly, these are pregnant women. Numerous ultrasounds, tests, tests, examinations - all these tests must be passed by the expectant mother to give birth to a healthy child. The list of necessary tests for pregnant women includes a coagulogram. These analyzes characterize hemostasis and allow early detection of disturbances in this system. In the body of the expectant mother, many processes go differently than before pregnancy. In particular, the activity of hemostasis increases, which is normal.

However, there are also deviations from the norm. And this is already becoming dangerous for both mother and child. Disturbances in the functioning of blood systems can lead to irreparable consequences. In order to detect and neutralize all kinds of problems in time, a hemostasiogram is performed.

What is the activation of the hemostatic system associated with during pregnancy?

Firstly, a woman’s hormonal background changes.
Secondly, a new (uteroplacental) circulation appears.
Thirdly, the pregnant woman’s body prepares for inevitable blood loss during the birth of the child.

If there is a blood clotting disorder during pregnancy, there is always a danger of developing the so-called (disseminated intravascular coagulation), which is characterized in the first stage and hypocoagulation in the second, that is, leads to. DIC syndrome is considered one of the most serious complications in obstetrics, is often uncontrollable and poses a danger not only to the life of the fetus, but also to the life of the woman.

The opposite situation is possible. Due to a violation in the anticoagulant system, the blood becomes very thin. As a result, the risk of bleeding increases, especially during childbirth. In order to restore hemostasis, an analysis and further interpretation of the coagulogram is carried out. Based on the results of the study, treatment is prescribed.

Normally, this test is performed in each trimester of pregnancy. Unscheduled if:

The woman had miscarriages.
Symptoms are observed preeclampsia: swelling of the extremities, protein in the urine.
Uterine hypertonicity (threat of miscarriage) is diagnosed.

There are many reasons for impaired hemostasis, but women whose relatives have had a heart attack, stroke, varicose veins, or diseases of the blood system should pay special attention to their condition.

Important! Among pregnant women, there is a widespread belief that any medications are harmful to the unborn child. But the hemostatic system is not something to joke about. A timely study and taking the necessary medications will help a woman carry and give birth to a healthy child.

Study of hemostasiogram

After a blood test, the coagulogram is deciphered. What indicators can be seen in a laboratory report, and what do they mean?

1. Fibrinogen

This enzyme is synthesized in the liver. Normally, this figure ranges from 2 g/l to 4 g/l. For pregnant women, its increase is considered normal, but the fibrinogen content, even in the third trimester, should not exceed 6 g/l. This is a very sensitive factor. Its reaction to inflammation and tissue necrosis has been established. An increase may also indicate infections, acute inflammatory processes (pneumonia), the onset of a heart or brain infarction, hypothyroidism, burns, or contraception. If the amount of fibrinogen decreases, one may suspect a lack of vitamins (C, B 12), hepatitis, toxicosis, taking certain medications, or cirrhosis of the liver. And, of course, the infamous DIC syndrome.

2. APTT

The time it takes for a blood clot to form is examined. This indicator reacts sharply to changes in other coagulation factors. The normal APTT is from 30 to 40 seconds. An increase in the parameter may indicate a lack of vitamin K or liver disease.

3. Prothrombin

Thrombin is synthesized from this protein in the liver when exposed to vitamin K. By changing the value of this factor, the state of the gastrointestinal tract and liver is judged.

4. Lupus anticoagulant

This indicator is assessed mainly during a hemostasiogram in case of suspected antiphospholipid syndrome or other autoimmune disease. IgM and IgG antibodies to phospholipids are produced in the blood (normally they are absent), which contribute to an increase in the aPTT rate. Their appearance indicates gestosis or autoimmune diseases. Usually this situation ends in failure: the woman loses her child.

table: normal values of the basic coagulogram

5. Thrombin time

Shows the time it takes for fibrinogen protein to be converted to fibrin. The normal setting is from 11 to 18 seconds. Since the amount of fibrinogen increases during pregnancy, it is logical to assume that thrombin time also lengthens. However, the indicator still does not go beyond the norm. If the data is deviated from the norm, then this may indicate a lack or excess of fibrinogen in the blood.

6. Prothrombin time

This indicator means the time of thrombin formation from its inactive form (prothrombin protein). Thrombin is needed to form a blood clot, which helps stop bleeding. If this indicator is increased, hypovitaminosis K, deficiency of coagulation factors, and liver disease can be diagnosed.

7. Prothrombin index

One of the most important indicators. The clotting time of normal plasma is compared to the same time in the patient. PTI is expressed as a percentage. The normal rate should be between 93-107%. A change in PTI may signal liver disease, risk. An increase in the rate may occur during pregnancy or when taking contraceptives. If blood clotting properties deteriorate, the PTI will be lowered. Since the prothrombin index is directly related to vitamin K, a decrease indicates a lack of this vitamin or poor absorption in the intestine (for example, with intestinal ailments). Taking aspirin or also lowers PTI levels.

8. Platelets

Blood cells that are directly involved in maintaining hemostasis. The norm in the blood of these cells is from 150,000 to 400,000 per μl. If the indicator decreases, it is diagnosed. This may indicate that the mother is undernourished. Platelets are synthesized in the bone marrow.

9. Antithrombin-III

It is protein in nature and is an antagonist of the thrombin enzyme. Its role is to inhibit the action of the coagulation system. This parameter is expressed as a percentage. The norm is from 71 to 115 percent. If the parameter decreases by half, the risk of thrombosis increases. In case of increased blood clotting, anticoagulants are prescribed. In this case, monitoring of the indicator is also necessary.

10. DIC syndrome

Normally, the coagulation and anticoagulation systems are in balance. If any of the factors of these systems is disturbed, the entire hemostasis becomes unbalanced. This is especially dangerous in pregnant women. The most serious complication is disseminated intravascular coagulation. Activation of the coagulation system and fibrinolysis stimulates the development of DIC syndrome. As a result of the development of pathology, a pregnant woman may experience placental abruption, endometritis, etc.

11. D-dimer

As a result of incomplete disintegration of fibrin fiber, rather large “fragments”—D-dimers—appear. This is one of the main indicators of a coagulogram for pregnant women. The general norm is less than 500 ng/ml. However, other parameters are considered normal in pregnant women. Already at the beginning of pregnancy, the indicator begins to increase, and before childbirth it exceeds the norm several times. An increase may also be observed in patients with diabetes mellitus, with kidney disease, during complicated pregnancy (preeclampsia), and in old age.

12. Antibodies to phospholipids (Antiphospholipid syndrome)

The disease is autoimmune. The amount of antibodies to phospholipids begins to increase in the body. This is a series of symptoms that characterize arterial and venous thrombosis. Pregnant women diagnosed with APS are at risk of losing their baby due to fetaplacental insufficiency.

13. Plasma recalcification time

Indicator of fibrin protein clot formation. This parameter reflects the coagulation process as a whole.

14. Plasma tolerance to heparin

This test is carried out simultaneously with the previous one. Heparin is added to the plasma and the time of plasma recalcification is noted. If this indicator is less than normal, changes in other factors of the coagulation system are possible. Liver cirrhosis and hepatitis are suspected. With an increase in the parameter, one can assume the presence in the body of diseases such as prethrombosis, malignant tumors. However, normally an increase in the indicator can occur in the last stages of pregnancy.

Important! It should be noted that decoding of a coagulogram during pregnancy (as, indeed, for all other patients) can only be carried out by a specialist. It is unacceptable to diagnose yourself based on one data or another and prescribe treatment.

Where can I get tested and how much does it cost?

Anyone can take a blood test such as a hemostasiogram at one of the nearest medical centers, if it has the necessary equipment and reagents at its disposal. The cost of a coagulogram depends on the range of services and equipment of the center. Basically, the price of the basic package varies from 700 to 1,300 rubles (in Moscow). An extended coaguloramma costs about 3,500 rubles.

However, for pregnant women, a coagulogram is included in a number of mandatory studies and is carried out free of charge. Under the compulsory medical insurance system, you can also get a test completely free of charge, having first received a referral from your attending physician.

How to submit?

The question “how to take it” in the case of a coagulogram test is not at all superfluous. The results of the study depend on proper preparation of the patient. This analysis is carried out in vitro(in vitro - outside the body). Blood is taken from a vein.

Blood is donated on an empty stomach. The last meal should be no later than 8-12 hours before the test. You cannot drink any drinks (coffee, tea, and especially alcohol). Only clean water is allowed. The medications you are taking - especially those that affect the blood clotting process - must be indicated at the time of the test. The emotional state of the patient is very important. You need to try not to be nervous, to be calm and balanced. Muscle overstrain also negatively affects the results of the study. It is useful to drink an additional glass of cold water right before taking the test. Interpretation of the results is carried out only (!) by a specialist.