Blood test for fibrinogen: normal, low

One of the most important functions of the blood is the ability to "curl up" or thicken when bleeding occurs. Thanks to this property, the wound itself heals over time, and the person does not bleed. In the process of blood coagulation, an important role is played by fibrinogen protein. A blood test for fibrinogen is an important study carried out before operations, during pregnancy, in preparation for childbirth, during the diagnosis and treatment of inflammatory, cardiovascular diseases, etc. On the properties and the rate of this substance in the body talk today.

Table of contents:
  • What is fibrinogen in the biochemical analysis of blood
  • Norm
  • Norm of fibrinogen during pregnancy
  • Fibrinogen reduced: what does it mean?
  • How to take an analysis?
  • How to reduce fibrinogen during pregnancy
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What is fibrinogen in the biochemical analysis of blood

If the integrity of the vessel or tissue is compromised, the body gives a signal to hemostasis, that is, the formation of a crust( clot) at the wound site. Then from the liver various compounds are released into the blood, among which there is fibrinogen. This is a protein that, on appearance, is in an inactive state, it is activated only at the last stage of the occurrence of a blood clot. Activation occurs under the action of platelets and other substances. In the course of biochemical reactions, fibrinogen is converted into fibrin monomer, and then into the insoluble fibrin polymer.

Thus, when asked what fibrinogen is, the easiest way to answer is this: it is a protein produced in the liver and involved in the process of blood clotting. Abnormal blood levels can cause bleeding or blood clots in the vessels.

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As with any blood test, there is a set interval of optimal values ​​for fibrinogen. For adults, they are 1.8-4 g / l. Newborns have slightly lower rates: 1.2-3 g / l. The rate of fibrinogen in the blood of women and men does not differ by sex, but during periods of pregnancy or menstruation, the figures may differ from those given above.

For a more accurate diagnosis, along with determining the level of fibrinogen in the blood, it is worthwhile to have information about other blood parameters such as ESR, platelet count, etc.

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Fibrinogen norm in pregnancy

During pregnancy, the level of this protein is increased compared with the established norm, with its maximum in the third trimester of pregnancy. This is due to the body's readiness for a large blood loss, which, if necessary, will be quickly stopped by fibrin and blood clots.

Fibrinogen standards during pregnancy are as follows:

Until the 13th week: 2.1-4.3 g / l;

14-21 week: 2.8-5.2 g / l;

22-30 week: 3–5,6 g / l;

week 31-35: 3.3-5.7 g / l;

week 36-42: 3.6-6.5 g / l.

As you can see, the rate of fibrinogen during pregnancy is significantly higher than that of all people, but this does not mean that it should not be followed. Regular blood donation is very important for expectant mothers, since even minor deviations can have a very negative impact on the health of the baby, on the health of the woman, and on the progress of the birth. After the appearance of the child, the protein level will return to its previous optimal performance.

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Fibrinogen lowered: what does it mean?

A decrease in this protein in the blood can be congenital or acquired as a result of any disruptions or diseases of the body. Since this compound is produced by the liver, a decrease in its level may suggest a deviation in the work of this particular organ. Diseases that trigger low fibrinogen:

  • Hepatitis;
  • Cirrhosis;
  • Chronic leukemia;
  • Polycythemia;
  • DIC.

Fibrinogen can also be lowered as a result of poisoning with snake venom, vitamin C and B12 deficiency, toxicosis, amniotic fluid embolism in the newborn, or imperfect hemostasis in young children.

If fibrinogen is lowered, the reasons may be hiding in the medication. Fish oil, vitamin E, certain hormonal preparations, anabolic steroids, and others can reduce blood clotting by reducing fibrinogen.

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How to take an analysis?

Blood to determine the level of fibrinogen is taken from a vein. In this case, the patient is recommended to take an analysis on an empty stomach, after at least 8 hours has passed since the last meal. The most reliable result will be obtained when donating blood in the morning. Before analysis should be avoided:

  • Exercise;
  • Stress;
  • Taking drugs that affect blood clotting or the hormonal system. If it is not possible to cancel these medicines, you must inform the doctor about them;
  • Smoking and Alcohol;
  • Fatty Food.
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How to reduce fibrinogen during pregnancy

If the protein level in the blood exceeds 6.5 g / l in the third trimester of pregnancy or begins to increase sharply in earlier periods, this is a warning signal for the doctor. Thus, the liver reacts to the occurrence of the source of infection. Diseases that cause high fibrinogen levels in expectant mothers include colds, pneumonia, myocardial infarction, cancer tumors. In addition to diseases, burns can be affected by a particularly large area, surgical interventions and hormonal intake.

In order to determine in time the deviation of fibrinogen in the blood, pregnant women should strictly monitor the performance of their blood, and this can be done only if you pass all tests on the schedule recommended by the doctor.

Restoration of fibrinogen to the limits of the norm is associated with the treatment of the underlying disease. If a blood test abnormality is caused by a pregnancy or an inflammatory disease, the fibrinogen level itself will recover after recovery.