HCG levels during pregnancy by days from conception. HCG and successful pregnancy HCG 5 3 what is the due date

(HCG) is a hormone produced by a woman’s body during pregnancy. HCG appears immediately after fertilization and allows you to determine pregnancy as early as 4-5 days. HCG is produced by the chorion and continues to grow until the 12-13th week of pregnancy - the maximum rate of the hormone at this moment is 90,000 mU/ml, after which the rate begins to decrease. For example, the hCG rate at week 19 already varies between 4720-80100 mU/ml. HCG norms by day and week allow you to monitor the development of pregnancy in the first trimester, identify possible pathologies and developmental abnormalities.

Determination of hCG

HCG levels are determined in several ways. The most accurate results are provided by a blood test, which can detect pregnancy even before a missed period. By examining hCG norms by obstetric week, an experienced doctor will be able to accurately determine the duration of pregnancy and possible pathologies (the threat of miscarriage).

Less accurate data is provided by a urine test, although this is what all home pregnancy tests are based on. It is worth noting that while determining the hormone norm in a blood test for hCG makes it possible to monitor the progress of pregnancy, a urine test does not provide such accurate data.

Beta-hCG norms by week:

• 1-2 weeks – 25-156 mU/ml;
• 2-3 weeks – 101-4870 mU/ml;
• 3-4 weeks – 1110-31500 mU/ml;
• 4-5 weeks – 2560-82300 mU/ml;
• 5-6 weeks – 23100-151000 mU/ml;
• 6-7 weeks – 27300-233000 mU/ml;
• 7-11 weeks – 20900-291000 mU/ml;
• 11-16 weeks – 6140-103000 mU/ml;
• 16-21 weeks – 4720-80100 mU/ml;
• 21-39 weeks – 2700-78100 mU/ml.

All established hCG standards, whether analyzed at 4 weeks or 17-18 weeks, are relevant for the normal course of a singleton pregnancy. If there are two or more embryos, the hormone levels will be several times higher. For example, in a normal intrauterine pregnancy, the hCG rate at week 3 is on average 2000 mU/ml and continues to double every 1.5 days. Thus, by 5-6 weeks, a hCG level of about 50,000 mU/ml is considered normal.

It is worth noting that a low hCG level may indicate termination of pregnancy, that is, fetal death. Insufficient growth of the hormone also indicates an ectopic pregnancy and the threat of miscarriage. At a period of 15-16 weeks, the hCG level, the norm of which should be in the range of 10,000-35,000 mU/ml, in combination with the results of other tests, is used to identify pathologies in fetal development.

"We explained the purpose of determining the level of hCG in the blood, as well as the general trend in this indicator during pregnancy. However, we did not dwell in detail on the hCG norms by week. These values ​​are necessary to determine the normal or pathological course of your pregnancy. Let us warn you right away: managing pregnancy, including ordering tests and their interpretation, is the work of a professional. Only a qualified doctor can adequately assess the condition of a woman and her fetus, but it will be much easier for him if the woman is informed about the hCG levels by week, and at the same time trusts him and follows the instructions.

Changes in hCG levels during pregnancy

Before we begin to describe the hCG level by week, we should dwell on the features of the analysis itself. Human chorionic gonadotropin consists of two fractions - alpha and beta. Alpha-hCG is identical to the components of some other hormones that are in no way related to the presence of pregnancy, while beta-hCG is highly specific: this fraction is produced exclusively by the chorion.

Home tests, so-called test strips, are based on the reaction of hCG of both subunits, but when determining hCG in the blood, they use a technique that captures only a specific beta fraction.

The second important point: any laboratory technique has its own sensitivity threshold. Please note that hCG standards for weeks of pregnancy, although they begin from the first week of embryonic development, however, at this period the results are practically no different from hCG levels in non-pregnant women. You should not run to the laboratory the very next day after the expected conception - this is a waste of money and time. The earliest period at which laboratory diagnosis of pregnancy is possible in some cases is 7-8 days after the expected conception. However, here too, gynecologists recommend not to rush, but to conduct the study only after a delay.

When determining hCG by week, they focus on several main points:

a reading of up to 5 mIU/ml is considered negative;

an indicator from 5 to 25 mIU/ml is doubtful and requires repeating after a few days;

When assessing deviations from the hCG norm by week, a difference exceeding 20% ​​of the standard is taken into account. A decrease or increase in hCG levels by 50% or more is considered a pathology.

A deviation of 20% usually requires repeat analysis. If a repeated study reveals an even greater deviation from the norm, a conclusion is drawn about the presence of a pathological process, but if the result remains the same and there is no clinical picture of pregnancy complications, elevated hCG is considered as a variant of the individual norm.

A single test of hCG levels is rarely used - it is only relevant for the early diagnosis of pregnancy. To identify pathological conditions (threat of abortion, feto-placental insufficiency, etc.), the dynamics of changes in hCG are observed.

So how does the hCG level change by week of pregnancy? Its growth is especially pronounced in the first weeks, then the increase in the rate slows down somewhat and it stabilizes. The increase in hCG value over the weeks is usually expressed in the time required to double its concentration in the blood. Initially, it only takes 2 days for hCG levels to double. Starting from 5-6 weeks this figure is already 3 days, at 7-8 weeks - 4 days. By 9-10 weeks, the concentration of hCG reaches its peak and subsequently decreases slightly, reaching the norm for 6-7 weeks by 16 weeks. In the second half of pregnancy, the dynamics of hCG levels by week are not subject to sharp fluctuations: for the remaining time, its level is only about 10% of its maximum at 10 weeks, increasing slightly on the eve of childbirth.

HCG levels are very variable between weeks of pregnancy. The initial increase is explained by the intensive growth of the fetus, the child's place and active hormonal changes in the female body: at this time, the chorion secretes a large amount of hCG to prepare the place for the baby and provide conditions for its successful development. But after 10 weeks, the placenta undergoes significant changes: now it is not so much a hormonal organ as a respiratory and nutritional one - after all, it is thanks to the placenta that the fetus receives nutrients and oxygen. This explains the decline in the increase in hCG in the blood.

HCG readings by week

To make it more convenient to navigate the hCG indicators by week, it is customary to present the standards in the form of a table.

What should you consider when comparing results with table data?

The hCG table by week shows obstetric weeks, which are counted from the date of the start of the last menstruation. That is why you will not see the hCG rate at 2 weeks here - during this period we are not talking about any pregnancy, because Conception itself occurs only at the end of this very second week or at the beginning of the third.

To make it easier to navigate when comparing the embryonic (from conception) and obstetric (from the last menstruation) periods, you can take it as a rule that the first is always 2 weeks behind the second.

If your result shows a slight increase in hCG (more than 5 mIU/ml), remember that before reaching 25 mIU/ml, the result is considered doubtful and requires repeating in 2-5 days.

The hCG level by week is not an absolute norm: there are minimum acceptable, maximum and average values. However, even if your result does not fit within the specified framework, the criterion for prescribing an additional examination (repeated hCG study, analysis of estrogen and progesterone) is usually considered to be a deviation of more than 20%. And even in this situation, it may turn out that this deviation is a variant of the individual norm, so do not draw your own conclusions - entrust this matter to a specialist.

In each case, the obtained indicator should be compared with the hCG norms for weeks that are accepted in the laboratory where you took the test. This is explained by the fact that different institutions may use different methods, so compare your result with the data indicated on the laboratory form.

The hCG calculator will help you decipher the results of a blood test for hCG in dynamics by day from the date of conception, embryo transfer (after IVF) or delay, determine the length of pregnancy and assess the dynamics of growth in hormone levels.

HCG doubling period in singleton pregnancy

HCG begins to be produced already 6-10 days after fertilization of the egg. In the first weeks, your hCG levels should double approximately every 2 days. As the gestational age increases, the rate of its growth slows down - when the level reaches 1200 mU/ml, hCG doubles every 3-4 days (from 72 to 96 hours), and after 6000 mU/ml the doubling occurs on average every 4 days (96 hours).

PM - according to the date of the last menstruation.
DPO - days after ovulation.

The concentration of hCG reaches its maximum at 9-11 weeks of pregnancy, then the level of hCG begins to slowly decrease.

During multiple pregnancies, the hCG content increases in proportion to the number of fetuses, and on average, hCG levels in pregnant women with twins (triplets) are usually higher than in other pregnant women at the same stage.

Laboratory standards and user results

HCG standards may vary in different laboratories. This is due to the use of various research techniques, reagents and other factors. Therefore, to correctly assess the dynamics of hormone growth, it is necessary to conduct research in one laboratory and evaluate the results relative to the standards of this laboratory. The hCG calculator allows you to evaluate your results relative to the standards of different laboratories:

The results of other users on the graph may also differ (depending on laboratory standards) and contain errors (for example, data was entered incorrectly).