One of the most accurate methods for determining early pregnancy is a blood test for the amount of hCG hormone content. The human chorionic gonadotropin beta particle is a unique glycoprotein unit that is produced after the embryo attaches to the uterus. Its blood levels vary depending on the timing of pregnancy and play an important role in the synthesis of the hormones estradiol, progesterone and estriol. It will not be difficult for those who are interested in their “interesting” position to accurately determine the presence of pregnancy by donating blood for hCG. What it is, how the procedure goes, when to go through it and how to evaluate the results, we will consider in the article.
What is HCG?
Human chorionic gonadotropin is a hormone with a protein structure. It is produced by the tissues of the developing embryo throughout the entire period of gestation. Thanks to this substance, ovarian function is inhibited. New eggs cease to mature, and the next menstruation does not occur. HCG sets up the female body for carrying a pregnancy, contributing to the implementation of hormonal changes.
This glycoprotein consists oftwo particles: alpha and beta. The alpha hCG is similar to other body hormones, while the beta unit is unique. Therefore, during the analysis, they are guided precisely by the concentration of the beta particle.
A small presence of the hormone in the human body is considered normal even in the absence of pregnancy. It is produced by the pituitary gland. Sometimes a certain amount of the hormone is found in the body of men and non-pregnant women. The norm of hCG in the blood is up to 5 mIU / ml, and for women during menopause - up to 9.5 mIU / ml.
How to determine pregnancy by blood test?
The level of human chorionic gonadotropin in a woman's body has become a universal indicator of pregnancy. Express strips are arranged just according to this principle. They respond to the level of the hormone in the urine, which begins to increase markedly as early as 2 weeks after fertilization. However, the tests are not always accurate, and besides, with their help it is impossible to accurately tell the gestational age. Therefore, women who are planning to conceive are advised to donate blood for hCG. What is it? A common procedure performed in any private or public laboratory.
The results obtained are highly accurate. Many women are interested in the question: “When will blood on hCG show pregnancy?” Obstetricians and gynecologists recommend taking your time and thinking about conducting an analysis only after a delay. The minimum period after which it is possible to determine pregnancy is 7 days from the moment of conception.
When can I donate blood for hCG?
Despite the fact that the blood test -a highly accurate and affordable method that allows you to find out about pregnancy, you should think about the timing of its implementation. Of course, nothing prevents you from contacting a diagnostic laboratory within a couple of days after conception. But the results of such an analysis will not be reliable. And yet, when can you donate blood for hCG in order to get accurate pregnancy data? Doctors recommend the following timing:
- if a woman knows exactly the day of conception, then 2 weeks must be counted from it. On the received date and schedule the analysis;
- in cases where it is impossible to determine the moment of conception, it is advisable to take an analysis after 3 weeks from the day of missed menstruation.
To obtain reliable results, you should be patient and wait for the recommended time.
How to get tested and how much does it cost?
Women inexperienced in pregnancy and motherhood ask a lot of questions about analysis. How to take hCG, what rules must be observed? In fact, everything is much simpler than it seems. Blood for hCG is taken from the cubital vein in the amount of 5 ml. It is advisable to come to the analysis in the morning and do not eat anything before the procedure. Before getting a referral from a doctor, it is better to warn about taking medications. This may affect the results of the study.
What is the cost of an HCG blood test? The price may vary depending on the laboratory. On average, the service will be 500 rubles, in the capital - about 800 rubles. This applies to private clinics and diagnostic centers. ATA budgetary institution at the place of residence issues a referral free of charge.
Interpretation of primary results
Having decided when it is better to donate blood for hCG, having gone through the procedure and having received the coveted result, I want to know more about what the numbers on the analysis statement mean. Three scenarios are possible:
- Negative - the hormone is defined as 0 to 5 mIU/ml.
- Questionable - chorion values are fixed in the range of 5–25 mIU/ml.
- Positive - HCG in the blood exceeds 25 mIU/ml.
If you get a questionable result (a slight increase in the hormone), it is recommended to re-analyze after a few days. At the same time, it is desirable to comply with the same conditions for blood sampling and diagnostics: to come to the same clinic, at the same time of day and on an empty stomach. The new result is compared with the previous one. If the deviation in one direction or another is preserved and exceeds 50% of the norm, a conclusion is made about the presence of a pathological process (a sign of tumors). In the case of a 20% deviation from the established values, the result is again called into question, appointing a new study. In some cases, with the stability of the results and the absence of pathologies, a conclusion is made about the individual level of the hormone of chorion in the blood.
A single test is performed only if a negative result is obtained, of which there is no doubt over time. When pregnancy is confirmed, it is necessary to periodically monitor the blood hCG hormone.
Changestest results by week of pregnancy
In the first weeks of pregnancy, the level of the hormone chorion in the blood increases significantly. Growth rate is considered in days needed to double it:
- up to 6 weeks – 2;
- 6-8 weeks - 3;
- 8-10 weeks – 4.
By the 11th week of pregnancy, the result of a blood test for hCG will show the maximum value. After that, a gradual decline will begin. At 16 weeks, the indicator will be identical to a 7-week pregnancy. For the rest of the gestation period, the hormone levels will remain stable.
| Week from conception | HCG level, mIU/ml |
| 1 | 50-100 |
| 2 | 2 500-6 500 |
| 3 | 11,000-25,000 |
| 4 | 36,000-73,000 |
| 5 | 64,000-116,000 |
| 6 | 27,000-233,000 |
| 7–11 | 20,000-291,000 |
| 12–15 | 6 200-103 000 |
| 16–20 | 4 800-80 100 |
| 21–39 | 2 700-78 100 |
The variation in the level of the chorionic hormone is very high: all options are in the specified rangeare considered the norm. In addition, only a doctor can reliably interpret the results. Sometimes the individual level of the hormone in the blood is slightly higher or lower than the standard.
HCG indicators for IVF
If a woman has undergone an IVF procedure, then the procedure for conducting the analysis will change somewhat. When will blood on hCG show pregnancy in this case? The answer of the experts is as follows: the procedure should be completed no earlier than 12 days after the injection with the content of the hormone chorion. The table shows the average values of hCG in the blood after implantation of the embryo into the uterine cavity.
| Embryo age (count day of puncture as zero) | Average hCG, mIU/ml |
| 1 | 4 |
| 2 | 105 |
| 3 | 2,000 |
| 4 | 11 500 |
| 5 | 31,000 |
| 6 | 65,000 |
How to donate hCG, if injections with its content were prescribed after implantation of the embryo in order to maintain the functioning of the corpus luteum? You should wait a few days before doing the analysis. Otherwise, the results will be inflated.
High levels of hCG in the blood
Most pregnant women are practically unaware of their hCG levels. If everything is in order, the doctor rarely tellsexpectant mother about the results of each examination. Another thing is when problems arise. HCG in the blood may be higher or lower than normal. And with only rare exceptions, this does not indicate the pathology of the development of the fetus or the he alth of the mother.
What do the overestimated numbers in the results of the analysis for hCG hide behind? Sometimes nothing serious: incorrect setting of the term or multiple pregnancy. However, suspicion often falls on the presence of diabetes in a woman, toxicosis, or pathologies in the development of the embryo. If an elevated level of hCG in the blood is detected, a second analysis and an additional examination of the expectant mother are prescribed.
Low HCG
The level of the hormone chorion in a woman's blood allows not only to detect pregnancy in the early stages with high accuracy, but also to monitor the development of the embryo throughout the entire period of gestation. HCG is a specific hormone of motherhood. His underestimated indicators, as a rule, indicate violations of the course of pregnancy:
- threatened miscarriage;
- delayed development of the embryo;
- fetal death;
- "fading" germ;
- ectopic pregnancy;
- pathology of the placenta or fetus.
Any deviation from the norm in the results of the analysis for hCG is an alarming sign that requires immediate medical attention for advice.
Should I rely on the results of the analysis?
And yet, blood for hCG - what is it? How much can you trust a typical laboratoryanalysis? This procedure is similar to taking blood for hormones, because hCG is one of them. The reliability of the result is high: inaccuracies are rare, usually due to medication or the use of specific products on the eve of the analysis.
Laboratory tests may produce a false positive or false negative. In the first case, a high level of hCG, typical for a pregnant woman, will be determined. Only after a while it turns out that the embryo is absent in the uterine cavity. Why is this happening? There are few options: either the drugs taken by the woman (including those containing hCG) are to blame, or this is a serious sign of pathology.
False negatives usually occur when testing is done too early. There are also anomalies in the development of the embryo in the early stages. In any case, a second analysis and ultrasound are prescribed.
Conclusions
HCG blood - what is it? It turns out to be a standard and very informative analysis. With its help, it is possible to diagnose pregnancy with high accuracy already 2 weeks after conception. HCG is a specific hormone produced by the tissues of the chorion (subsequently the placenta). After implantation of the embryo into the uterine cavity, its number increases dramatically, stimulating the restructuring of the body for bearing the fetus. HCG indicators characterize pregnancy in the best possible way and notify the expectant mother in time not only about the “interesting” situation, but also about disruptions in the development of the baby.
