2 embryonic week of pregnancy, the norm of hCG. The norm of hCG by week is your safe pregnancy. Types of tests for hCG

An analysis for hCG is familiar to most pregnant women, but many of them think that it is only necessary to establish the fact of pregnancy.

In fact, it allows not only to determine the presence and duration of pregnancy, but also to identify possible complications of its course.

With special attention, the dynamics of this indicator is monitored in those women who have had unsuccessful pregnancies in the past.

Human chorionic gonadotropin is a special hormone that begins to be synthesized in the female body with the onset of pregnancy.

In women who are not expecting a child, this hormone may also be present in the blood, but in a small amount.

The norm is 0-5 mU / ml, which does not suggest the presence of pregnancy.

The hCG hormone, or rather β-hCG, begins to be produced after the implantation of the embryo into the epithelium of the uterus (7-10 days after the fertilization of the egg). It is synthesized by the cells of the chorion - the fetal membranes of the embryo, which are subsequently converted into the placenta.

The hormone is needed to ensure the normal functioning of the corpus luteum - a special gland that is located in the ovary and produces hormones that contribute to the normal course of pregnancy.

In the absence of pregnancy, it cannot produce large amounts of estrogen and is absorbed after a while.

In addition, hCG helps the female body to rebuild and adapt to the stressful state caused by pregnancy.

(test strips) react to the presence of a hormone in the urine. This method is less accurate than a blood test because the concentration of hCG in the blood is twice as high as in the urine.

Sometimes a laboratory analysis can give a false negative result (there is a pregnancy, but the analysis does not confirm this). This can happen due to violation of the rules of blood donation, late ovulation or implantation of the ovum. In these cases, a second blood donation is usually prescribed after a few days.

In order for the results of the analysis to be correct, several conditions must be met:

• the analysis can be taken 12-14 days after ovulation, otherwise it will be unreliable;
• blood from a vein is given in the morning on an empty stomach. If this is not possible, you can donate blood during the day. Before this, you need to refrain from eating for several hours;
• on the eve it is recommended to avoid fatty foods, stress and physical exertion;
• if a woman has taken hCG preparations, she needs to report this to the laboratory.

These rules can be neglected if an urgent determination of the concentration of hCG is necessary (for example, if a pregnancy is suspected or not developing). Such cases are characterized by a sharp deviation of the value from the normal level and the result will still be obvious.

The dynamics of the growth of the hormone

The concentration of hCG in the blood less than 5 mU / ml indicates the absence of pregnancy, above 25 mU / ml - that the woman will become a mother.

A result in the range of 5-25 mU/mL is considered doubtful and requires re-analysis after a few days.

The rate of change in hCG depends on the duration of pregnancy. In the early stages of pregnancy, it grows rapidly, while every 2 days its value doubles.

After the hCG value reaches 1200 mU / ml, it takes 3 to 4 days to double.

When the threshold of 6000 mU / ml is reached, the level rises 2 times every 4 days.

The growth of hCG continues until 10-12 weeks of pregnancy, then its value gradually decreases.

This is due to the fact that by the end of the first trimester of pregnancy, the formed placenta takes over the function of hormonal support. The corpus luteum becomes unnecessary and disappears, so there is no need to synthesize a large amount of hCG.

After that, the concentration of hCG is approximately at the same level until the very birth.

Norms for weeks of pregnancy is a very arbitrary concept, because each medical laboratory uses its own norms. More important is not the absolute value of hCG, but the dynamics of its growth.

The results of the obtained analyzes should be interpreted only by a doctor, taking into account the norms of the laboratory and the individual characteristics of the woman.

If it is necessary to track the growth of hCG in dynamics, all analyzes must be done in one laboratory. Different medical centers may have different laboratory methods and standards, so the analysis data may not be correct.

Table: hCG levels by week of pregnancy

The main indicators are presented in the following table.

Causes of elevated hCG levels

Exceeding normal values ​​is possible in the following cases:

• error in determining the gestational age;
• diabetes;
• 2 or more fetuses develop in the uterus.

HCG during pregnancy with twins grows faster, that is, the existing norms can be safely increased by 1.5-2 times;

• malformations of the fetus, including Down syndrome;
• prolonged pregnancy.

A common cause of high hCG during pregnancy is taking drugs that are prescribed to stimulate ovulation (Pregnil, Horagon).

A re-analysis for hCG is carried out in the second trimester of pregnancy during the course of the test, which allows you to identify abnormalities in the development of the fetus.

Only according to the results of screening, Down syndrome and other defects are not confirmed, the woman simply falls into the risk group. For accurate diagnosis of pathology, other methods are used (

Diagnosis of pregnancy pathologies is not limited to a blood test for hCG.

For the final diagnosis, additional research methods are used, in particular, ultrasound.

Elevated hCG in the absence of pregnancy

Exceeding the permissible level of hCG in the blood of men and non-pregnant women most often signals the formation of a malignant tumor. An increase in hormone levels can be caused by the following factors:

• testicular tumor in men;
• cystic skid;
• malignant tumors of the genital organs, gastrointestinal tract, kidneys;
• analysis was given a short period of time after the abortion.

After an abortion or spontaneous miscarriage, hCG continues to be determined in the blood for some time. Normally, its value during pregnancy should decrease.

If hCG continues to increase, this indicates that there are tissues of the fetal membranes in the uterus that continue to produce the hormone.

In this case, the woman is shown curettage of the uterine cavity, followed by control of hCG and ultrasound.

Tracking the level of hCG during pregnancy will allow you to identify deviations in the development of pregnancy in time and determine the right tactics for their elimination.

The interpretation of blood tests for hCG should be entrusted to the doctor, because the norms are rather arbitrary and the woman herself will not be able to correctly “read” the result.

The most important indicator of a successful pregnancy is hCG, or human chorionic gonadotropin. A special table of hCG by weeks of pregnancy allows you to control the proportional relationship between the age of the embryo and the level of its hormonal background.

Outside of pregnancy, this hormone is not produced. Cases of the appearance of hCG in men and women indicate the beginning of hormone-producing processes, that is, the formation of various types of tumors.

The main task of a qualitative laboratory analysis is to determine the hormonal β-subunit and compare it with the general table of hCG norms.

HCG level during pregnancy (table of hCG norms)

It is difficult to overestimate the enormous role that chorionic gonadotropin plays in the body of a pregnant woman. This hormone, produced by a fertilized egg, determines all the necessary vital processes for the normal course of pregnancy, prevents the regression of the corpus luteum, and enhances the hormonal synthesis of progesterone and estrogen.

If we analyze the hCG table by day of the week, we can see that chorionic gonadotropin in the blood plasma is determined already on the 9th day after ovulation, at the very moment when the fertilized egg is introduced into the endometrium. Every two days, during the normal course of pregnancy, the concentration of hCG constantly doubles, reaching its maximum value of 50,000-250,000 mU / l. This happens at 8-10 weeks of pregnancy after the start of the last menstruation in women. Analyzing the summary table of hCG during pregnancy, you can see that the level of chorionic gonadotropin in the blood plasma begins to decrease sharply after the specified period, and later, after 18-20 weeks, the hCG readings remain stable until the end of pregnancy.

Each woman can determine in laboratory tests and compare her performance with the norm, focusing on the general table of hCG during pregnancy, which indicates tolerant values. If there are any deviations from the norm, then attention should be paid to this.

HCG during pregnancy (norm by week, table):

Pregnancy, week by week	Mean value, mU/ml	Max and min limits, mU/ml

For convenience, in the hCG table for weeks of pregnancy, the average value is displayed, which should be paid attention to during the next test for the detection of human chorionic gonadotropin.

What determines the level of hCG in blood plasma?

There are various reasons on which the reduced or increased level of chorionic gonadotropin in the blood plasma of a pregnant woman depends. So, the reasons for the increased level of human chorionic gonadotropin (hCG) may be as follows:

• the adoption of chorionic gonadotropin as a therapeutic pharmacological agent;
• high blood sugar, or diabetes;
• multiple pregnancy;
• various pathologies associated with genetic engineering by chromosomal composition;
• problems with the development of trophoblast cells, causing various kinds of neoplasms.

A decrease in the level of hCG concentration can occur for various reasons:

• chromosomal abnormalities and defects in the development of the embryo (fetus);
• ectopic or ectopic pregnancy;
• intrauterine or antenatal fetal death;
• missed pregnancy and other causal factors.

Artificial or in vitro fertilization (IVF)

If a couple is unable to naturally conceive a child, there is an IVF method or in vitro fertilization. This method, due to various reasons associated with dysfunctions of the reproductive organs, is increasingly used in modern life. The essence of the method is to extract the egg from the female body, fertilize it with a sperm outside the natural environment by chemical and biological laboratory manipulations. Subsequently, the resulting embryo is placed in the uterus, where it continues its development. An important point is the control of the survival of the embryo. The hCG table after the transfer of embryos into the female body allows you to track the dynamics of successful fertilization by day in terms of all biological indicators of the state of the embryo in the uterine cavity.

Below is a table of hCG after IVF, reflecting the hormonal increase in terms of pregnancy after artificial insemination is normal:

Pregnancy from conception (by day)	Optimal level (max, min) hCG, mU/ml.
	from 25 to 156
	from 101 to 4870
	from 1111 to 30500
	from 2500 to 82500
	from 23000 to 142000
	from 27500 to 235000
	from 21000 to 295000
	from 6000 to 105000
	from 4500 to 81000
	from 2500 to 80000

Determination of hCG in ectopic conception

If a fertilized egg does not enter the uterine cavity, it develops outside the uterine walls, more often in the fallopian tube, which is the connecting anatomical link between the smooth muscle hollow organ (uterus) and the abdominal cavity. This condition is called an ectopic pregnancy, which, due to the growth of the fetus in unnatural conditions, can lead to serious consequences, even death. However, even with an ectopic conception, the results of laboratory testing determine the chorionic gonadotropin in the blood plasma.

An alarming signal is a significant increase in the β-subunit, which exceeds the norm by 2-2.5 times in the first week of pregnancy. Therefore, the detection of ectopic conception at an early stage is very important for the female body.

However, determining the symptomatic signs of pregnancy outside the uterine cavity in the initial phase is not an easy task, which depends on many individual physiological parameters. Let's define the symptoms that most often occur in women with an ectopic conception:

• pain in the lower abdomen, which is pulling in nature;
• constant nausea and dizziness;
• gagging;
• increase in body temperature.

However, the main alarm signal is scant spotting, which is an unnatural indicator of a suspected pregnancy. For a more detailed definition of an ectopic pregnancy, an urgent appeal to the antenatal clinic is necessary, where an abnormal condition can be accurately determined using ultrasound scanning.

HCG is human chorionic gonadotropin, a hormone that is actively produced by the cells of the chorion (fetal membrane) immediately after it attaches to the wall of the uterus. The "production" of this hormone is vital for the preservation and maintenance of pregnancy! It is hCG that controls the production of the main pregnancy hormones - estrogen and progesterone. With a serious lack of hCG, the fertilized egg is detached from the uterus, and menstruation occurs again - in other words, a spontaneous miscarriage occurs. Normally, the concentration of hCG in the blood of the expectant mother is constantly growing, reaching a maximum by the 10-11th week of pregnancy, then the concentration of hCG gradually decreases to remain unchanged until the very birth.

What are the norms of hCG during a normal pregnancy, and what is the level of hCG during an ectopic pregnancy? Pregnant women receive special tables in laboratories that show what the level of hCG should be at different stages of pregnancy.

When deciphering the obtained analysis for hCG, follow the following rules:

1. In most laboratories, the gestational age is indicated "from conception", and not from the date of the last menstrual period.
2. When evaluating the results of the analyzes, always check the standards of the laboratory that performed your analysis. Since different laboratories may have different levels of hCG during pregnancy
3. If your hCG level differs from the norm of the laboratory - do not panic! It is best to decipher the analyzes in dynamics. Retake the analysis in 3-4 days and only then draw conclusions.
4. If you suspect an ectopic pregnancy, be sure to undergo an ultrasound scan to make an accurate diagnosis.

NORM HCG IN THE BLOOD IN WOMEN DURING PREGNANCY

HCG levels during pregnancy honey/ml (INVITRO laboratory standards)

HCG values ​​ranging from 5 to 25 mU / ml do not allow confirming or disproving pregnancy and require re-examination after 2 days.

For the first time, an increase in hCG levels can be detected using a blood test approximately 11 days after conception and 12-14 days after conception using a urinalysis. Since the content of the hormone in the blood is several times higher than in the urine, therefore, a blood test is much more reliable. In a normal pregnancy, in 85% of cases, the level of beta-hCG doubles every 48-72 hours. With increasing gestational age, the time it takes for it to double can increase to 96 hours. HCG levels reach their peak in the first 8-11 weeks of pregnancy, and then starts to decrease and stabilizes during the remaining period.

HCG norms during pregnancy

The human chorionic gonadotropin hormone is measured in milli-international units per milliliter (mIU/mL).

An hCG level of less than 5 mIU / ml indicates the absence of pregnancy, and a value above 25 mIU / ml is considered a confirmation of pregnancy.

As soon as the level reaches 1000-2000 mIU / ml, transvaginal ultrasound should show at least the fetal sac. Since during pregnancy, normal levels of hCG in different women can vary significantly and the date of conception can be calculated erroneously, the diagnosis should not be based on ultrasound results until the hormone level reaches at least 2000 mIU / ml. The result of one analysis for hCG is not enough for most diagnoses. To determine a healthy pregnancy, multiple measurements of human chorionic gonadotropin are needed with a difference of a couple of days.

It is worth noting that these figures should not be used to determine the duration of pregnancy, as these numbers can vary greatly.

To date, there are two types of routine blood tests for hCG. A qualitative test determines the presence of hCG in the blood. A quantitative hCG test (or beta-hCG, b-hCG) measures exactly how much of the hormone is present in the blood.

HCG levels by week

HCG levels by week from the start of the last menstrual period*

3 weeks: 5 - 50 mIU/ml

4 weeks: 5 - 426 mIU/ml

5 weeks: 18 - 7340 mIU/ml

6 weeks: 1080 - 56500 mIU/ml

7-8 weeks: 7650 - 229000 mIU/ml

9-12 weeks: 25700 - 288000 mIU/ml

13-16 weeks: 13300 - 254000 mIU/ml

17-24 weeks: 4060 - 165400 mIU/ml

25-40 weeks: 3640 - 117000 mIU/ml

Non pregnant women:<5 мМЕ/мл

After menopause:<9,5 мМЕ/мл

* These figures are only a guideline - the level of hCG by week for each woman can rise in different ways. It is not so much the numbers that are important, but the trend in the level change.

Is your hCG pregnancy normal?

To determine if your pregnancy is going well, you can use hcg calculator below on this page

By entering two hCG values ​​and the number of days that have passed between tests, as a result, you will find out how long it takes for your beta hCG to double. If the value corresponds to the normal rate at your gestational age, then everything is going well, and if not, you should be alert and conduct additional checks on the condition of the fetus.

HCG doubling rate calculator

At the beginning of pregnancy (the first 4 weeks), the hCG value doubles approximately every two days. During this time, beta-hCG usually manages to rise to 1200 mIU / ml. By 6-7 weeks, the doubling rate slows down to about 72-96 hours. When beta-hCG rises to 6000 mIU / ml, its growth slows down even more. At the tenth week of pregnancy, the maximum is usually reached. On average, it is about 60,000 mIU / ml. Over the next 10 weeks of pregnancy, hCG decreases by about 4 times (to 15,000 mIU / ml) and remains at this value until childbirth. 4-6 weeks after delivery, the level will be less than 5 mIU / ml.

Increasing hCG levels

Men and non-pregnant women:

1. chorioncarcinoma, recurrence of chorioncarcinoma;
2. hydatidiform drift, recurrence of hydatidiform drift;
3. seminoma;
4. testicular teratoma;
5. neoplasms of the gastrointestinal tract (including colorectal cancer);
6. neoplasms of the lungs, kidneys, uterus, etc.;
7. the study was conducted within 4 - 5 days after the abortion;
8. taking hCG drugs.

Pregnant women:

1. multiple pregnancy (the level of the indicator increases in proportion to the number of fetuses);
2. prolonged pregnancy;
3. discrepancy between the real and the established gestational age;
4. early toxicosis of pregnant women, preeclampsia;
5. maternal diabetes;
6. fetal chromosomal pathology (most often with Down syndrome, multiple fetal malformations, etc.);
7. taking synthetic gestagens.

Decreased hCG levels

Pregnant women. Alarming level changes: inconsistency with the gestational age, an extremely slow increase or no increase in concentration, a progressive decrease in the level, more than by more than 50% of the norm:

1. ectopic pregnancy;
2. non-developing pregnancy;
3. the threat of interruption (the level of the hormone decreases progressively, by more than 50% of the norm);
4. true prolongation of pregnancy;
5. antenatal fetal death (in II - III trimesters).

False negative results (non-detection of hCG during pregnancy):

1. the test was performed too early;
2. ectopic pregnancy.

Attention! The test has not been specifically validated for use as a tumor marker. HCG molecules secreted by tumors can have both normal and altered structure, which is not always detected by the test system. The results of the test should be interpreted with caution, in comparison with clinical data and the results of other types of examination, they cannot be considered as absolute evidence of the presence or absence of the disease.

Level HCG in ectopic pregnancy will be significantly lower than the specified standards and this will allow you to respond in time to the current situation.

An analysis of the level of free b-hCG is used in the screening of intrauterine development and the presence of fetal pathologies in the first trimester of gestation. This test is carried out between 11 and 14 weeks of embryonic development. Its purpose is to identify possible pathological changes in development in the form of trisomy 18 or 13 pairs of chromosomes. Thus, you can find out the child's tendency to ailments such as Down's disease, Patau and Edwards syndromes.

This test is carried out not as a determination of the predisposition of the fetus to the above ailments, but in order to exclude them, therefore, special indications for the analysis are not required. It is as planned as an ultrasound at week 12.

Increasing hCG levels during pregnancy may occur when:

• multiple pregnancy;
• toxicosis, gestosis;
• maternal diabetes;
• fetal pathologies, Down syndrome, multiple malformations;
• incorrectly established gestational age;
• taking synthetic gestagens, etc.

Elevated values ​​can also be seen within a week when taking an analysis after the abortion procedure. A high level of the hormone after a mini-abortion indicates a progressive pregnancy.

Low hCG levels during pregnancy may indicate a miscalculation of the gestational age or be a sign of serious disorders, such as:

• ectopic pregnancy;
• non-developing pregnancy;
• delay in fetal development;
• the threat of spontaneous abortion;
• chronic placental insufficiency;
• fetal death (in the II-III trimester of pregnancy).

Rules for preparing for a blood test for hCG during pregnancy

1. Blood donation should take place in the morning (from 8 to 10 days). Before taking the test, it is better not to eat fatty foods, do not have breakfast in the morning.
2. The day before blood sampling, it is strictly forbidden to drink alcohol, drugs and engage in physical activity.
3. A couple of hours before the test, do not smoke, do not drink anything other than plain water; eliminate stress and emotional instability. It is better to rest and calm down before the test.
4. It is not recommended to donate blood after physical procedures, examinations, massage, ultrasound and radiography.
5. If it is necessary to retake the test in order to control the indicators, it is recommended not to change the conditions for donating blood (time of day, meals).

HCG test during pregnancy - meaning

Firstly, an analysis of the level of hCG in the blood can confirm that you will become a mother already 5-6 days after conception. This is much earlier and, most importantly, much more reliable than using conventional rapid tests.

Secondly, a test is needed to determine the exact gestational age. Very often, the expectant mother cannot give the exact date of conception, or she calls it, but incorrectly. At the same time, certain indicators of growth and development correspond to each period, deviations from the norm may indicate the occurrence of complications.

Thirdly, the level of hCG in the blood can quite accurately “tell” whether your baby is developing correctly.

An unplanned increase in the level of hCG usually occurs with multiple pregnancy, preeclampsia, taking synthetic progestogens, diabetes in the expectant mother, and can also indicate some hereditary diseases in the baby (for example, Down syndrome) and multiple malformations. An abnormally low level of hCG can be a sign of an ectopic and non-developing pregnancy, fetal growth retardation, the threat of spontaneous abortion, and chronic placental insufficiency.

However, do not rush to sound the alarm: increased or decreased values ​​\u200b\u200bmay also indicate that the gestational age was initially set incorrectly. Your doctor will help you interpret the test results correctly.

The chemical structure of hCG and its role in the body

Glycoprotein is a dimer with a molecular weight of about 46 kDa, synthesized in the placental syncytiotrophoblast. HCG is made up of two subunits: alpha and beta. The alpha subunit is identical to the alpha subunits of the pituitary hormones TSH, FSH, and LH. The beta subunit (β-hCG) used for the immunometric determination of the hormone is unique.

The level of beta-hCG in the blood as early as 6-8 days after conception makes it possible to diagnose pregnancy (the concentration of β-hCG in the urine reaches the diagnostic level 1-2 days later than in the blood serum).

In the first trimester of pregnancy, hCG provides the synthesis of progesterone and estrogens, necessary to maintain pregnancy, by the corpus luteum of the ovary. HCG acts on the corpus luteum like a luteinizing hormone, that is, it supports its existence. This happens until the "fetus-placenta" complex acquires the ability to independently form the necessary hormonal background. In the male fetus, hCG stimulates the Leydig cells that synthesize testosterone, which is necessary for the formation of male reproductive organs.

The synthesis of hCG is carried out by trophoblast cells after implantation of the embryo and continues throughout pregnancy. In the normal course of pregnancy, between 2 - 5 weeks of pregnancy, the content of β-hCG doubles every 1.5 days. The peak concentration of hCG falls on the 10th - 11th week of pregnancy, then its concentration begins to slowly decrease. With multiple pregnancies, the content of hCG increases in proportion to the number of fetuses.

Decreased concentrations of hCG may indicate an ectopic pregnancy or threatened abortion. Determining the content of hCG in combination with other tests (alpha-fetoprotein and free estriol at 15-20 weeks of pregnancy, the so-called "triple test") is used in prenatal diagnosis to identify the risk of fetal abnormalities.

In addition to pregnancy, hCG is used in laboratory diagnostics as a tumor marker for tumors of trophoblastic tissue and germ cells of the ovaries and testes that secrete chorionic gonadotropin.

HCG: table of norms by week of pregnancy. Possible errors and pathologies

Thoughts of pregnancy occur in a woman after a few days of delay in menstruation. By that time, the embryo is already several weeks old. HCG was not without reason dubbed the hormone of pregnant women, it is actively produced only by "ladies in position" and is determined by the most.

The table of hCG indicators is guided not only in the diagnosis of early pregnancy. It is needed for:

• comparisons when observing the correct formation of the fetus;
• timely detection of developmental anomalies.

Normally, the hormone is found in the body of both sexes, but its concentration does not exceed 5 U / ml.

• What is hCG and why is it important during pregnancy
• Normal level outside of gestation
• Period of active hormone synthesis
  • When to take an analysis
  • Why HCG is out of date
• Reasons for deviations
• When to donate blood for research
• How often do you get tested in the 1st trimester?
  • Indications
  • Mistakes
  • Is it possible to take hCG in the evening
• Preparation for analysis
• HCG growth table during pregnancy by week
• Dynamics of hCG by day from conception (table)
• Characteristic changes in hormone levels in genetic pathologies
• When does a natural decrease in hCG occur during pregnancy

Chorionic gonadotropin and its role

Chorionic gonadotropin is a glycoprotein consisting of a pair of components:

• alpha particles or alpha subunits;
• beta particles or beta subunits.

Actually, the beta component of the hormone is a kind of marker of the onset and successful course of pregnancy. HCG is produced by the primary embryonic membrane - the chorion, from the first days of conception.

The main role is to block the menstrual cycle, prevent bleeding and spontaneous rejection of the embryo. It activates the production of estradiol - hormones responsible for retaining a fertilized egg in the body of the uterus, as well as the proper formation and nutrition of the placenta.

The concentration of the hormone in the blood outside of pregnancy

In a non-pregnant woman, the level of gonadotropin is low - from 0 to 5 IU / ml. The increase in indicators is fixed:

• some time after ;
• in menopause (up to 9 U / ml);
• against the background of long-term therapy with hormonal drugs;
• in the presence of tumor-like formations of the genitourinary system.

In men, an increased amount of the hormone in the blood indicates the development of a tumor process in the reproductive sphere.

The period of active production of hCG

Active production of gonadotropin begins on the 5-7th day from conception, during this period the increased level is diagnosed only in the venous blood. On days 8-10, the concentration of the hormone is such that it is freely excreted in the urine. Not everyone knows what it is - hCG, but it is on the principle of detecting a hormone in urine that the work of test strips is built.

The quantitative peak of gonadotropin is fixed on - I trimester. Further, its indicators gradually decrease and increase in accordance with the gestational age.

When is the first test scheduled?

If the planned term of conception is known, you can take an analysis on the 7th - 9th day. If there are doubts about the day, blood is given after 4 days of delayed menstruation. For the accuracy of the result, the analysis is repeated after 2 days.

With successful fertilization, the indicator increases every day by one and a half to two times. If the concentration of hCG remains the same or fluctuates slightly, another reason should be sought. After a week of delay in menstruation, you can use a test strip for determining gonadotropin in the urine.

Why the increase in hCG does not correspond to the expected timing?

Often, the dynamic growth rates of the hormone go against the deadlines set by the gynecologist. This disturbs the woman, forcing her to think about pathology. Indeed, with some developmental anomalies, a lag in the level of gonadotropin is observed. But it is important to remember that hCG is used to judge the duration of pregnancy from the moment of conception, and the doctor counts the weeks from the last menstruation.

Note! An analysis of hCG reliably establishes the fact of pregnancy, but not its duration. To determine the age of the fetus, it is better to use the ultrasound method.

Factors of deviation from the norm

The obtained indicators during pregnancy may not correspond to the hCG standards from the table for various reasons.

When the level of gonadotropin is above normal:

1. With the wrong deadline. In the first trimester, a difference of 5-6 days gives significant deviations. Therefore, it is possible to compare the tabular data with your results, but it should be understood that the hCG table during pregnancy is only a guideline and it is important not the exact correspondence of the numbers, but the dynamics of their growth.
2. With multiple gestation. The concentration of gonadotropin is proportional to the number of embryos. So with a double, the norm is multiplied by two, and with a triple, by three.
3. After therapy with hormone-containing drugs based on progestogen.
4. At .
5. With a genetic abnormality in the fetus.

In addition, the result of the analysis is affected by an increase in blood sugar.

When a low concentration of hCG is determined:

1. With the wrong deadline.
2. . The amount of the hormone is increasing, but at a reduced pace.
3. . The level of hCG drops sharply down by 40 - 50%.
4. With reduced blood supply to the placenta and insufficient nutrition.

Any deviation from the norm requires a retake, to eliminate errors, and additional examination methods.

Self-determination of the fact of pregnancy, when to take the test?

In the average woman, fertilization occurs in the middle of the cycle - during the period of ovulation. The egg cell journey takes 5-7 days. Once in the uterine cavity, it attaches to the wall, it is during this period that the production of hCG begins in the pregnant woman (this is clearly seen in the table).

The first analysis can be carried out on the 8-10th day after intercourse, but it should be remembered that the level of the hormone is not yet high. A result of 25 IU/mL and below is considered controversial. The optimal delivery time is 3-4 days of delayed menstruation. The amount of gonadotropin increases daily by about half. For the purity of the result, it is recommended to retake two days later in the same laboratory.

Important! HCG table standards have a wide range. With a healthy pregnancy, the outcome will vary from woman to woman.

Frequency of examination in the first trimester

Twice with a break of several days, blood is donated for primary diagnosis and establishment of the fact. If the course of pregnancy does not inspire concern, the study is repeated at 11 - at the end of the first trimester. This study includes the detection of the level of three hormones, the change of which gives an idea of ​​the development of abnormalities in the fetus.

If it is necessary to follow the dynamics of growth, the doctor may prescribe a study of the amount of gonadotropin for 2 to 4 weeks with a break of 4 to 5 days. This approach is used for women at risk. The next one is being held.

Indications for analysis

In what cases does the detection of the “hormone of pregnancy” become an important part of the diagnosis:

• first-time amenorrhea;
• tracking the dynamics of the course of pregnancy;
• indication of ectopic development of the embryo;
• the threat of intrauterine death of the fetus;
• the threat of spontaneous abortion;
• identification of anomalies in the formation of the child's anatomical and genetic;
• suspicion of the development of a malignant tumor process.

Are there errors in reading hCG?

HCG, like any medical analysis, can give false readings, although the error rate is not high.

Reasons for a false positive response:

1. hormone therapy with progestin preparations;
2. increased synthesis of gonadotropin as a result of a malfunction of the controlling organ - the pituitary gland;
3. development of neoplasms of the reproductive sphere;
4. endocrine diseases.

In these cases, the test results show pregnancy in its actual absence.

The reverse situation is a false-negative test in the presence of a fertilized egg, which develops with insufficient production of gonadotropin:

1. too early analysis;
2. and the exit of the fetal egg into the uterine cavity;
3. ectopic development of the embryo.

Is it possible to take a hormone test in the afternoon?

The maximum amount of hCG in the blood and urine is fixed in the morning after sleep. Therefore, all studies are carried out before 10 am on an empty stomach. This condition is especially important in the early stages, when the concentration of the hormone is not yet high. By evening, the level of gonadotropin decreases several times, which provokes a false result.

Rules for passing the analysis

The delivery of hCG does not require special preparation. The rules common to all blood tests apply here:

• a light dinner the day before, the exclusion of food on the day of delivery;
• it is recommended to drink a glass of clean water;
• reduce physical activity;
• do not smoke 7 - 8 hours before the study;
• all medications taken must be reported to the attending physician.

For research, venous blood is taken, which is then subjected to separation using a centrifuge. The term for decoding the data obtained in different laboratories is not the same, from 4 hours to a week.

Change in indicators by week of gestation

For clarity, consider the growth of hCG in the table by week of pregnancy.

Table 1: HCG by weeks of pregnancy from conception

There is another calculation system - according to the days of the cycle from the moment of ovulation.

Table 2: HCG rate during pregnancy by day

The described norm for the days of ovulation shows the upper and lower limits, based on the average menstrual cycle.

HCG changes in genetic abnormalities

Gonadotropin is a kind of marker of genetic and anatomical abnormalities in the development of the fetus.

• almost twice the norm may indicate the risk of Down syndrome;
• persistently low levels of gonadotropin - suspicion of Edwards or Patau syndrome;
• subtle dynamics may indicate the development of Turner's syndrome.

The discrepancy between the indicators of the gestational age is recorded during the formation of heart defects or underdevelopment of the neural tube in the embryo.

Attention! The hCG indicator only raises suspicion of the possible development of anomalies. To establish the fact of a genetic abnormality, an additional examination is prescribed.

Natural decrease in hCG

The peak of blood saturation with gonadotropin is observed at -e, after which there is a slight uniform decrease to approximately. The level stabilization period continues until the 40th week, until the moment of resolution. A week and a half after childbirth, the concentration of hCG returns to the norm inherent in the pre-pregnancy state.

In some cases, a sharp jump in the tested hormone is observed in the third trimester, and is considered as the result of the occurrence of pathological conditions, for example,.

A woman can check her blood for hCG on her own, which does not require a doctor's referral. But only a specialist is able to correctly interpret the result with a positive answer. Tables are presented for reference.

Actual video

Preparation for analysis for hCG during pregnancy and decoding