AFP analysis: norm, decoding

The birth of the planned baby is eagerly awaited by many parents. At the same time, being in the position, the future mother is forced to take a considerable amount of various analyzes. Among them there is also an analysis of AFP. And if the study for progesterone is almost universally known, then alpha-fetoprotein, or AFP, is not well known to anyone.

Recently, more and more people are turning to laboratories for research on oncomarkers. These substances have different nature: they can be proteins or their derivatives, special enzymes, hormones. They are the products of the life of a tumor or are produced by our body in response to an attack of cancer cells. AFP is also an oncomarker, and it will be described in this article. In total, the specialists installed 20 of them.

What is AFP?

As mentioned above, AFP analysis refers to the category of research on oncomarkers, which signal how exactly pregnancy takes place. This antigen is normally produced directly by the embryo in the body of a pregnant woman. But after the birth of a child, his production takes place in the liver.

Usually any body, including the future child, in the body perceives immunity as an alien. And since the embryo is not such a body, a certain amount of alpha-fetoprotein protects the fetus from rejection by the body. Initially, the synthesis of the antigen occurs in the yellow body of the ovaries. With the onset of the fifth week of pregnancy, the obligation to produce AFP takes on itself a fetus.

At the same time, its concentration increases in the blood of the mother and in the blood of the baby. The highest content of this protein, as shown by the AFP analysis, is observed at 32-34-th week. After the birth of the child and during the first year of his life, the content of AFP comes back to normal.

Important role of AFP during pregnancy

The role of protein is difficult to overestimate, because it is the guarantor of the preservation of the fetus and prevents attempts at spontaneous abortion. But sometimes it is produced in too much or too little. This circumstance should alert any professional gynecologist. In such cases, this may indicate that the fetal bladder is developing incorrectly. Sometimes this is a signal that there are some problems that concern the development of the child at the genome level.

The level of AFP content can show the AFP analysis, which is performed after 12 weeks of pregnancy. At this time, the level of alpha-fetoprotein will reach a significant limit. If other digits are present during the correct interpretation, then probably there are any deviations.

However, accurate diagnosis based on an analysis of alpha-fetoprotein alone is not possible, since errors occur. Its elevated level may indicate a different:

• Multiple pregnancies;
• Necrosis of the embryo's liver ;
• Anencephaly;
• Umbilical hernia;
• Kidney pathology.

The development of internal organs with anomaly also leads to an increase in the level of AFP.

The reduced concentration of alpha-fetoprotein may be a sign that:

• There is a pathology of Down;
• There is a delay in embryo development;
• The death of the fetus occurred.

In some cases, with a low level of AFP, there is a risk of miscarriage. And sometimes its content is so low that on the basis of what AFP analysis shows (the norm in women or not), doctors come to the conclusion that pregnancy is false.

Abnormality in pregnancy

Any deviation in protein content from normal indices is an important criterion for monitoring the course of pregnancy. In this case, it becomes possible for the attending physician to prescribe additional studies in the course of which a particular diagnosis will be confirmed or refuted.

It is only necessary to note that the pregnancy can be interrupted not later than the 20th week. Shortly before this period, ultrasound is used as a control measure. ). In addition, it is important to check the level of hCG ( human chorionic gonadotropin ). If all the studies conducted confirm the fact that a child with high probability can be born with a pathology, the burden of making a responsible decision lies with the woman herself.

What else does the AFP indicate?

Not always an analysis of AFP during pregnancy, decoding is necessary only for future mothers. In some cases, this cancer marker is an important study in diagnosing a serious illness in adult patients. Normally the indicator is no more than 10 U / ml. An increase in this level suggests that a malignant tumor has developed in the human body, often with metastases. For more details on the AFP norm, see the special section below.

If the AFP content is below the norm, then this is a sign of abnormal processes in the development of the liver:

• Cirrhosis;
• Chronic hepatic impairment;
• Hepatitis B.

In addition, based on the state of the liver, we can conclude that there is or is not a chronic alcoholism.

Preparation for analysis

If the doctor has appointed such a study as the analysis of AFP and hCG during pregnancy, preparation is almost not required. Usually everything goes like with the usual blood sampling from the vein. And this means that in the next 5-8 hours you can not eat. In pregnant women, the term should be no less than 14 weeks. However, the interval between the 16th and 18th weeks is considered the most suitable for blood collection. The procedure itself is carried out in the morning, during which 10 ml of biomaterial is taken.

And since the procedure is performed on an empty stomach and is difficult, the patient after it needs to sit quietly, relaxed, for 15 minutes. In particular, this applies to expectant mothers. During this short period, the forces will recover, weakness will go away, and the risk of losing consciousness will decrease.

What can affect the analysis

In addition to proper preparation, it is important to take into account that some factors may distort the analysis of AFP during pregnancy. The norm is achieved if you follow simple rules. For dinner, it is best to refrain from eating food with various spices, as well as fatty, smoked and fried foods.

Such physiotherapy procedures as ultrasound and massage, as well as instrumental methods such as radiography, MRI, computed tomography, can also affect the analysis. Therefore, they are not recommended to be done on the same day as the AFP study. As for alcoholic beverages, their use should also be delayed. At least until the end of the analysis.

It was also noted that the representatives of the Negroid race have a higher concentration of AFP, while in the Mongoloid nation it is much lower. Another thing to consider is the presence of an endocrine disease like diabetes or viral diseases in the past.

Where it is possible to hand over the analysis?

At present, in any public or private laboratory, it is possible to take an AFP and hCG analysis during pregnancy. The norm will be known more precisely if in such institutions experienced experts who own the research methodology and the necessary equipment will be involved. The cost of such analysis is in the range of 300 to 600 rubles.

If you need to undergo such a study, you should not try to understand the result on your own, only the specialist should deal with decoding. And only an integrated approach will provide an accurate answer. That is, the most informative result is obtained if laboratory research is combined with instrumental. At the same time, data monitoring should be carried out in the same laboratory using a single reagent.

Interpretation of the analysis and AFP rate

After the analysis is done, the result will be ready in two days, but if necessary, in emergency cases, it can be obtained after two hours. Often, in order to have reliable data, in the second trimester of pregnancy, the analysis should be carried out in conjunction with ultrasound, research on placental hormones and other diagnostic techniques.

Each laboratory, when carrying out the analysis for the level of AFP content, uses its own methodology and reagents. . But in this case the units of measurement are denoted in all cases equally: IU / ml or MoM . при беременности, норма (МоМ) составляет 0,5-2. For example, if AFP and hCG are analyzed in pregnancy, the norm (MoM) is 0.5-2. However, if the laboratory uses other measures (IU / ml), the protein level, depending on the gestational age, will vary as follows (see table below).

As mentioned above, in men the norm is no more than 10 IU / ml. The same applies to non-pregnant women.

Indications for conduction

It is recommended that all pregnant women be evaluated for AFP no later than the 12th week of pregnancy. This is necessary to detect the presence or absence of deviations. And if they are absent, then the process proceeds in the normal mode. But if they are present, the attending physician prescribes a second analysis or additional studies.

просто необходимо без возражений. Sometimes it is necessary to donate blood for the analysis of AFP and hCG without objection. This applies to cases where a child is conceived by blood relatives, the baby was born with a developmental malformation or a pathology transmitted by inheritance. This is especially critical if a woman first becomes pregnant over the age of 35.

Still need to take into account the following situations:

• If a spontaneous miscarriage occurs during a woman's attempt to conceive.
• Admission of the mother before pregnancy or at the initial period of toxic medications that affect the embryo.
• The presence of any hereditary pathology or mutation at the genetic level in future parents.

In addition, it is simply necessary to undergo a study if, at an early gestation period, the woman underwent X-ray examination.