The hCG test is one of the first for a woman who is going to become a mother. It is made at home and in the laboratory, based on its results, they judge the fact of pregnancy, the gestational age, and even whether the baby is healthy.
What this analysis is, how it is carried out, how to understand its results and what to do in case of deviations from the norms, we will tell in this article.
What it is?
After fertilization has taken place, the blastocyst, being in constant division, moves into the uterus, which for the next nine months will become a "home" for the baby. This path runs through a pipe and takes an average of six to eight days.
If the goal is successfully achieved, the ovum gets the opportunity to "catch" on the uterine endometrium softened by progesterone. This process is called implantation.
It is from this moment that a special hormone begins to be produced inside the expectant mother. It is produced by embryonic structures, in particular the chorion. Therefore, the substance was named human chorionic gonadotropin, and in abbreviated form - hCG (permissible medical designations are FSHA, GPHa, GPHA1, HCG, LHA, TSHA).
The physiological function of this hormone, like all gonadotropic hormones, is the regulation of the work of the sex glands. In connection with the onset of pregnancy, they must produce quite certain hormones and substances so that the embryo receives the most optimal conditions for its growth and development.
The concentration of the substance in the blood of the expectant mother is constantly increasing, an increase occurs every 2 days. HCG reaches its peak by about 12 weeks of gestation, and then it begins to gradually decrease, since this hormone is no longer urgently needed for the development of the child - many hormones begin to be produced by the baby himself and the placenta formed by that time.
The chemical structure of the hormone is based on two subunits - alpha and beta. Alpha (α) completely repeats similar units of many other female hormones, therefore, it does not represent diagnostic value. But the beta hCG (β-subunit) has no analogues, it is different from all other hormones. It is on it that existing laboratory research and home tests for hCG are based.
The importance of this substance for carrying a baby is beyond doubt. Under the influence of chorionic gonadotropin, the corpus luteum does not dissolve, as it usually happens at the end of the cycle in non-pregnant women, but persists and serves as a source of the most important hormones - progesterone and estrogen. At 12 weeks, the placenta will take over the function of the corpus luteum, but there are no alternatives in the first three months of pregnancy.
Under the influence of hCG, the adrenal cortex begins to actively produce more glucocorticoids than usual. This helps the mother's body to more easily cope with the strongest stress, which is pregnancy.
Immunity under the influence of these substances begins to be somewhat suppressed, which allows the baby not to be rejected. Whatever one may say, but the embryo is only half akin to the mother's organism, the second half of its genetic set is alien to her immune defense. If the immune system is not “put down”, he will regard the embryo as a foreign object and will do everything possible to get rid of it.
A little later, when a young placenta appears, the chorionic gonadotropic hormone in every possible way contributes to its development, improves its structure, and makes it more functional.
HCG is not only found in pregnant women, it can be present in small amounts in both men and women who are not pregnant. The growth of the hormone in these categories of patients is considered a sign of pathology., usually - oncological or benign tumors. However, during pregnancy, the importance of gonadotropin is completely different.
Types of research, reliability
Research for HCG can be home and laboratory. Establishing the presence of free β-subunit is the basis of all familiar conventional pharmacy pregnancy tests.
Laboratory tests can be done with blood and urine samples. In the blood, the amount of gonadotropic hormonal substance rises earlier than in the fluid secreted by the kidneys, and therefore it is most likely to find out whether there is a pregnancy at all, at the earliest possible date, by a laboratory study of a blood sample.
In the course of laboratory research, traces of the free beta-subunit of hCG are detected in blood serum or in fluid excreted by the kidneys.
If you know that the level of gonadotropin increases approximately every two days, while increasing approximately twice, then it becomes clear that a day after implantation there is absolutely no way to find out whether pregnancy has occurred or not.
But within 4-6 days after implantation, the fact of pregnancy will become obvious to the laboratory assistant.
The hormone enters the urine from the blood when its concentration becomes high enough. Therefore, it makes no sense to do express tests from the nearest pharmacy or store before the delay begins.
To understand how the level of gonadotropin increases, you need to imagine its average amount for the days that have passed since the woman's supposed ovulation. The release of the egg occurs approximately on the fourteenth day of the cycle (if a woman has a standard one, 28 days). If the cycle lasts a little longer, for example, thirty days, then ovulation usually occurs on the 16th day.
From this moment, the countdown of the so-called DPO starts (these are the days after ovulation). We remember that the blastocyst is implanted only for 6-8 days, and therefore in the first 5 days the hCG level will not indicate the presence of pregnancy, and in general will not talk about anything.
From the moment of implantation, provided that the embryo is normally fixed, the dynamics will be something like this:
The growth of chorionic gonadotropin at the beginning of gestation:
The home test for HCG has a slight sensitivity - from 15 to 25 units. Therefore, even a good test cannot theoretically capture the concentration of the target substance in the urine prior to retention. The exceptions are cases when the amount of hCG is high, but we will consider these situations a little later.
When asked when a test can be done to find out exactly whether there is a pregnancy, the answer is quite simple - blood can be donated for research on days 8-10, if you count the time by days after ovulation, and you can start to soak a strip from the pharmacy in the morning portion urine from the first day of delay in the next menstruation.
Purpose of the analysis
The main and main purpose of such an analysis is to determine the very fact of pregnancy. However, a study can be ordered after this issue is clarified. There may be several purposes for this:
- it is necessary to clarify the duration of pregnancy (according to the quantitative level of the hormone, the doctor can make a conclusion about exactly when the implantation took place, and calculate the approximate period of conception);
- find an ectopic pregnancy (with it, the hormone level will be underestimated, and the ovum in the uterus will be absent);
- it is necessary to understand whether pregnancy is developing (if there are doubts about the normal development of the baby, about its viability, the analysis for gonadotropin, necessarily in dynamics at intervals of several days, will help to understand whether the baby is growing, or its development has stopped);
- diagnostics of the state of the placenta (during the period of bearing a child, an analysis for this hormonal substance may be needed if there is a suspicion of fetoplacental insufficiency);
- determination of the concentration of the hormone produced by the chorion is included in the screening diagnostics of the first and second trimester (according to its level, one can judge the likelihood of a child having chromosomal pathologies);
- the need to assess the effectiveness of the treatment provided with the threat of miscarriage (with the elimination of the threat, the hormone level usually returns to normal).
How is the analysis given? Training
A blood sample requires a sample taken from a vein. Blood should be taken on an empty stomach in the morning. A few days before this, fatty and spicy foods, hormonal drugs, if allowed by the attending physician, should be removed from the diet, and alcohol and strong coffee should be excluded.
Excessive physical activity can change the hormonal background of a woman, and therefore should also be abandoned. Severe stress and nervous shocks also affect the amount of certain hormones, and therefore you need to go to the laboratory after having a good sleep, in a calm mood.
To test urine at home or in the laboratory, you will need a morning portion of the fluid secreted by the kidneys. Before collecting urine a special pharmacy container with a lid should be purchased.
In the morning, a woman should thoroughly wash herself, close the entrance to the vagina with a cotton swab so that vaginal secretions do not get into the urine, and collect at least 60-100 ml of liquid in a container.
Before doing a home test, you need to carefully read the instructions for use. It cannot be violated, otherwise the results may be unreliable.
The strip is lowered into the collected urine to the level indicated on it, after a 30-second pause, the strip is removed and placed on a dry and clean surface. The result is evaluated within 5 minutes.
All the second stripes that appear after this time cannot be considered a reliable result. It should be remembered that defective express tests are often on sale, and therefore it is better to buy two different tests from different manufacturers and conduct them at the same time.
If laboratory testing of urine is planned, a tightly closed container of test fluid should be delivered to the laboratory as soon as possible, maximum 2 hours in advance. After this time, the diagnostic value of urine as a material is largely lost.
Decoding
Only a doctor can competently decipher the finished blood or urine test for the content of pregnancy gonadotropic hormone in them. But women who dream of pregnancy are very curious, as evidenced by their numerous posts on the topic of hCG on specialized forums on the Internet. To help them figure it out, for reference purposes only, we'll show you how this analysis is transcribed.
To begin with, it should be said that different laboratories measure the concentration of the hormonal substance in question using different diagnostic methods, respectively, they get different results. More often than not, the difference in the results of different laboratories lies in the difference in units of measurement. The concentration of the hormone is usually determined in:
- honey / ml;
- mIU / ml;
- mIU | ml;
- ng / ml.
Therefore, when women ask what the entry "0.1 mIU ml" means, it can be answered with confidence that the laboratory that analyzed her blood works according to the international standard, since the milli-international units in which the result is recorded testify precisely about it.
Most of the laboratories that exist today do not come to a consensus about the error in determining the concentration of a given substance, and therefore their results may differ from each other. In order to avoid confusion, doctors around the world decided to measure the norms of hCG in values that are multiples of the median (MoM). This made decryption much easier.
The norm for the content of hCG in pregnant women is any value that is in the range from 0.5 to 2.0 MoM. If in your result obtained in the laboratory, the value in MoM is not indicated, you should clarify in this medical institution which hormone indicators they take as the norm, and only after that proceed to deciphering.
HCG rates by week
To make it easier for future mothers who really want to know if their hormone level meets the norms, we made a summary table of values in different units of measure:
Indicators for multiple pregnancy
If a woman becomes pregnant with twins or triplets, then the level of human chorionic gonadotropin will be approximately doubled or tripled. The fact is that the chorion of each of the fruits produces its own "hormonal support", which adds up to high values in the analysis.
Knowledge of this feature of hCG allows one to suspect multiple pregnancy at the earliest possible date, before embryos can be examined and counted for ultrasound. As in the case of a singleton pregnancy, the level of the hormone rises during the bearing of several fetuses gradually, it also increases approximately twice every two days.
Multiple pregnancies can be suspected on the basis of not one analysis with increased values, but after two or three similar studies, which give a uniform increase in the concentration of the hormone in values that exceed the norm by 2-3 times.
In this case, the doctor will need to exclude some pathological conditions that can also cause increased hormone values, for example, cystic drift, the presence of diabetes mellitus in the expectant mother, and severe toxicosis.
Table of average rates of hCG when carrying twins:
To find out the norms typical for bearing triplets, the base values (for singleton pregnancies) should be multiplied by three. When carrying several babies, a woman should not rigidly rely on the existing table values, because the norms of chorionic gonadotropic hormone for several babies are very conditional and reflect only averaged values.
In each case, the indicators can be individual. It is not the specific numbers in the form of the analysis that are important, but the dynamics of their growth.
Indicators after IVF
If a woman cannot get pregnant on her own, modern methods of reproductive support, for example, IVF, come to her aid.
Fertilization takes place "in vitro", all this time a woman is being prepared for implantation of ready-made embryos (three-day or five-day) into her uterus using hormonal therapy. The countdown for such a woman begins after the transfer. DPP is the days after embryo transfer.
If the transfer of embryos was successful, and at least one of them took root, was able to implant and develops already by 4 DPP, the level of chorionic hormone begins to rise, but it does it somewhat more slowly - the increase occurs every three days.
It is precisely every three days that many women who have gone through IVF come to the laboratory to be tested for hCG. This helps to track how the embryo (embryos) is developing, whether rejection has occurred, because such a risk exists during in vitro fertilization.
Since to increase the chances of pregnancy in the uterine cavity, women are implanted not one embryo, but several, two or even three babies can take root. However, the analysis of hCG after IVF cannot answer the question of how many babies there will be.
He allows to suspect a multiple pregnancy only in the case of natural conception. And hormonal therapy before replanting leads the level of hCG to increased values even if only one crumb has taken root.It will be possible to clarify this issue at about 10-14 DPP five days during the ultrasound examination.
It is difficult to answer what the level of chorionic gonadotropin should be after IVF, it depends on the initial level of the hormone at the time of embryo transfer. If one baby has taken root, then the values will be slightly higher than the norms given in the table, typical for singleton pregnancy; but the excess will not be, as with twins, 2 times. If two babies take root, then the concentration of the hCG hormone in the blood and urine will grow more rapidly.
On average, growth will look like this.
Table of average values of hCG after IVF with engrafted twins:
Possible discrepancies
No other hormone causes as much discussion in women's forums as human chorionic gonadotropin. And all because women who dream of motherhood are ready to tirelessly do tests, donate blood at the nearest clinic and compare their results with the results of other similarly suffering people.
Some see "ghost stripes", others do not see them, and this also becomes a cause for concern. Let's look at the most common questions and problems that the fair sex has in connection with the definition of hCG.
Blood test positive, pregnancy test negative
This situation occurs most often when a woman rushed to do home rapid tests, because the concentration of a substance in the urine is growing slowly. The strip remained clean during the completed pregnancy, which is unambiguously shown by the laboratory result of a blood test.
The pharmacy test strip itself could be defective, or the woman could violate the instructions and conduct home testing incorrectly. With a high probability with a positive blood test, pregnancy is still there.
If the test is negative, and the results of the blood test are doubtful, that is, the level of the hormone is slightly higher than 5 units per milliliter, then the analysis is recommended to be repeated after about 4 days to see an increase in concentration if there is a pregnancy. If there is no growth, then it is highly likely that a woman develops a tumor process in the body.
Pregnancy test positive, blood test negative
In this situation, the home test should be repeated. If he determined pregnancy, and a blood test refuted it, then in the vast majority of cases there is no pregnancy. Probably, the test was performed with an error, was defective or expired, gave a false positive result.
If a repeated home test gives a positive result again, it is worth visiting a doctor who will give a referral for a more detailed examination, including an ultrasound scan and new laboratory blood samples for the concentration of chorionic gonadotropic hormone.
Slow growth or lack of dynamics of hCG may indicate an ectopic attachment of the ovum, non-developing pregnancy. It is important to understand that such a blood test will not be negative, but the values in it will be significantly lower than normal.
When to go for an ultrasound with a positive test?
The embryo on the monitor of the ultrasound scanner becomes visible at about 5 weeks of gestation. This is the obstetric countdown. If we speak in a simpler and more understandable language for women, then this is about three weeks from conception.
At this time, at high hCG values, it is already possible to see the number of fetuses, if, of course, the level of the equipment and the qualifications of the doctor allow it. The fetal heartbeat is heard from 6 weeks, while the level of hCG on average is already several tens of thousands of units per milliliter.
Even if the level of the hormone in the blood is high, and there can be no doubt about pregnancy, there is nothing to do for an ultrasound until 5 weeks, after all, the doctor most likely will not be able to see a tiny embryo that is less than a millimeter long.
If the hormone is above normal
If the level of chorionic gonadotropin is higher than that provided by the average tabular values used by all laboratories and doctors, then the situation requires additional examination.
The only non-pathological reason why the concentration of hCG in the blood and urine increases is the bearing of several fetuses. If two or more babies develop at the same time under a woman's heart, then an increase in the hormone is quite natural, and there should be no questions.
If ultrasound diagnostics completely excludes the likelihood of the birth of twins or triplets, then a high concentration of gonadotropic hormone may indicate the following pathologies.
Chromosomal pathologies of the baby
An increase in chorionic gonadotropin often accompanies gross malformations associated with an incorrect number or combination of chromosomes in the genetic set of the baby. You can confirm or deny this for more significant periods - after 9-11 weeks.
The amount of the hormonal substance is correlated with other proteins and hormones that are important for the presumptive conclusions in the screening. The final diagnosis is established only on the basis of invasive and non-invasive DNA methods.
Mom's diabetes
A pregnant woman does not always know that she has diabetes. Therefore, after receiving overestimated results of the analysis for hCG, a biochemical blood test is prescribed, which will allow to establish the sugar level.
If it is high, and the endocrinologist states that a woman has diabetes or gestational diabetes (developed only during and during pregnancy), then such a future mother will have increased control. If necessary, she will be prescribed treatment.
Gestosis
This is a dangerous condition for carrying a child, in which a woman has high blood pressure, edema, and the appearance of protein in the urine. The child begins to receive less nutrients and oxygen, as a result of which hormonal changes and changes.
In the early stages, gestosis is dangerous by miscarriage, at later stages - by premature or difficult childbirth, fetal death. Diagnosis of gestosis does not cause difficulties: if the analysis for hCG shows high values, the doctor will definitely give a referral for urine analysis to determine the protein in it and will control the weight and blood pressure of the pregnant woman.
Taking hormonal drugs
Not all hormonal drugs cause an increase in the level of chorionic gonadotropin hormone. This mainly concerns synthetic progestogens, which are often prescribed to pregnant women to preserve the baby, if there is a threat of miscarriage against a background of deficiency, for example, of progesterone.
Women who were able to become pregnant after treatment for infertility, in which gestagens were also included in the therapeutic course, may also show an increased level of hCG, especially in the very early stages of gestation.
Most situations in which the analysis for human chorionic gonadotropin shows too high results, are subject to medical correction. The child is able to bear and give birth.
The exception is cases with chromosomal abnormalities of the fetus, in which medicine is essentially powerless. The only thing that can be offered to a pregnant woman after confirming the diagnosis is to terminate the pregnancy for medical reasons.
If she wants to leave the child, despite the terrible diagnosis, the pregnancy will be maintained and all the necessary treatment will be provided, as is the case with healthy babies.
If the hormone is below normal
The values of hCG levels reduced relative to the existing norms can speak volumes. The most harmless reason for this phenomenon is a mistake in determining the duration of pregnancy.
If the doctor calculated the period longer than it actually is, if the implantation was late or ovulation occurred later, then the hormone levels may differ from normal by about 1-2 weeks. The error can also creep in if a woman does not remember on which day her last menstrual period began, if her cycle is irregular.
In all other cases, a reduced level of hCG may be a sign of the following pathological conditions.
Ectopic pregnancy
If the blastocyst is fixed not in the uterus, but outside it, in the tube, in the cervix, then the chorion hormone will be produced, but in much smaller quantities. Often, it is a reduced level of hCG that is the first sign of an ectopic pregnancy.
In this case, there is no way to save the baby. If the diagnosis is confirmed by an ultrasound examination or during a laparoscopic diagnosis, then the ovum is removed surgically, and in the case of a cervical pregnancy, the uterus must also be removed.
Anembryony
In this case, there is a chorion, and it produces a certain amount of a specific hormonal substance, but the embryo in the ovum is absent. This fact can be established on subsequent ultrasound, which will track the development of the ovum in dynamics.
The causes of the pathology are not fully understood, there are no options for maintaining such a pregnancy. The uterine cavity is subject to urgent curettage followed by treatment.
Frozen pregnancy
Under the influence of numerous factors, many of which are not fully understood, the embryo, which is normally fixed, may stop developing. In this case, the decrease in hCG will be quite natural.
Most often, the fetus "freezes" if an irreparable total genetic error occurred during fertilization, and the child's developmental defects are so extensive that he simply cannot grow and develop normally.
That is why it is recommended to do a genetic analysis of the tissues of the deceased embryoso that when planning your next pregnancy, take all measures to prevent the same outcome.
The baby can stop growing because of toxic substances, drugs and alcohol, if the mother abuses them, because of the poisons that can be in hazardous work, if the woman works there, because of the unfavorable environmental situation.
A woman is subjected to several tests for hCG, if they do not show an increase in the values of the hormone. If the level falls, ultrasound confirms the absence of vital activity and palpitations, surgical curettage of the uterine cavity and subsequent treatment are indicated.
Delayed baby development
Under the influence of various unfavorable factors, a lack of female sex hormones, the development of the crumbs can be delayed. This fact will also be reflected in the measurement of the concentration of chorionic gonadotropic hormone.
If the ultrasound confirms that the baby is alive, if the level of the hormone, albeit slowly, but growing, then it is possible to save the pregnancy. The woman is prescribed supportive treatment, taking vitamins and drugs to improve blood circulation, as well as hormonal agents, if the situation requires it.
Risk of miscarriage
If the baby meets the deadline for ultrasound, if he shows signs of vital activity, a reduced level of the hormone may indicate the threat of termination of pregnancy. In this case, the woman is prescribed treatment aimed at ensuring that preserve and prolong bearing.
Sometimes there is a need to use drugs containing hCG in injections. Usually such treatment gives effective results, and the child is saved.
Placental dysfunction
In chronic placental insufficiency in the second and third trimesters, hormone deficiency is affected due to the fact that the "child's place" does not cope with all its responsibilities, which include the production of the necessary hormones.
A decrease in hCG is observed in this case important for diagnosis and treatment initiation. Predictions depend on the degree of placenta insufficiency, the degree of intrauterine suffering of the child.
Postponing pregnancy
If the baby is in no hurry to be born, then at 40-42 weeks of gestation there is a physiological decrease in hCG due to "wear" of the placenta. She is aging, and this is quite natural, all her functions are reduced.
Determination of hCG in the framework of screening
The level of the hormone produced by the chorion, and then by the placenta, is important not only to find out if there is a pregnancy, but also to monitor the development of the baby in the early stages. The amount of the substance reaches its maximum by 12 weeks, it is at this time that the first prenatal screening is carried out.
It includes an assessment of the child's development by ultrasound and blood donation from a vein for hCG and a protein that is determined in the blood plasma of all women in an "interesting position" - PAPP-A.
It is important to know that the screening, which is usually scheduled from 10 to 13 weeks inclusive, takes place on one day - and donate blood, and do an ultrasound should be done with a minimum gap in time.
The results of the analysis in this case are considered only in conjunction with the data of ultrasound scanning, they cannot talk about any diagnoses, and only provide a basis for the presumptive calculation of the risks of having children with chromosomal abnormalities, such as Down's syndrome, Turner's syndrome, Patau, etc.
The norm of hCG at the first prenatal screening is a value that "fits" into the international average of 0.5-2.00 MoM. The same values are considered normal for the plasma protein PAPP-A.
If the levels of these criteria deviate from the norm, the free beta subunit of hCG at 12 weeks is increased against the background of a reduced PAPP-A protein, then they speak of the theoretical probability of the child having Down syndrome. If both indicators are lowered, then they talk about the likelihood of Edwards syndrome. This screening is considered the most accurate of all three antenatal screening tests, but a negative result is not a verdict. To speak with confidence about your baby's health, additional diagnostics are required. At this time, this is usually a chorionic biopsy or amniocentesis. These methods are invasive, they are unsafe for the mother and fetus, and pregnant women are warned about this.
If you don't want to take risks, but you need to find out the truth, you can choose a non-invasive method of DNA testing. This is a very expensive test that can be done starting from the 8th week of pregnancy, when the baby's erythrocytes begin to enter the mother's blood. Blood cells are isolated from a sample of venous blood, and from them - DNA, which will tell whether the baby has Down syndrome or other pathologies, and also answer the question of what gender the child is expected to be.
For the second time, the analysis for hCG is given as part of the so-called "triple test" in the second trimester of pregnancy. Together with it, the level of alpha-fetoprotein and free estriol is determined.
The increase in hCG levels in this case is also considered in the context of other meanings. Its significant excess on the period from 16 to 19 weeks, when a biochemical study of the second screening is prescribed, is considered as a possible sign of Down syndrome, and a decrease indicates Edwards syndrome.
In case of establishing high risks of having a sick child with chromosomal abnormalities based on the results of ultrasound and a second blood test, the woman is also shown a visit to a geneticist and subsequent additional invasive diagnosis.
She can also choose the non-invasive method, which was mentioned above, but in this case, one should prepare for the fact that several tens of thousands of rubles will have to be paid, and the result of such an analysis will not be the basis for terminating a pregnancy if a child is diagnosed with a disease.
You will still have to do an invasive test (amniocentesis, cordocentesis) so that a special expert committee consisting of geneticists and obstetricians-gynecologists can make an informed decision about the need to terminate the pregnancy for undisputed medical reasons, if the woman agrees to this.
What can affect the result of the analysis? Causes of errors
Only hormonal drugs can affect the result of the analysis for hCG. If ovulation had to be stimulated with the help of "Pregnil" or other similar drugs, traces of these substances can remain in the blood for a long time, giving false-positive results during pregnancy tests.
Erroneous results can also be with ovarian dysfunction, as well as with cystic drift or the presence of a tumor in the patient's body, even if she herself does not know about it.
An increased level of the hormone may indicate the effect of hormonal drugs to maintain pregnancy, especially pronouncedly affect the level of hCG "Dyufaston" and "Utrozhestan".
With long-term use of chorionic gonadotropin preparations, which happens during the treatment of infertility or in preparation for IVF, a woman may develop an inadequate immune response to the natural hormone produced by chorion. Hemotest helps to detect antibodies to hCG, which is carried out to find out what substances a woman is allergic to.
In practice, such an analysis is prescribed infrequently, mainly only in those cases if a woman has a history of several miscarriages or missed pregnancies in the early stages.
If the amount of antibodies exceeds the permissible limits (and each laboratory has its own), the woman is prescribed treatment, the situation is fixable. Most women who have autoimmune rejection of the hCG hormone, after a course of therapy and several sessions of plasmapheresis, manage to endure and give birth to a completely healthy and strong baby.
False negative results are much more common. They can be influenced by a woman's violation of recommendations regarding the timing of the examination. If the analysis is done too early, then the likelihood of getting a negative result with an already existing and developing pregnancy is high.
Another situation, which is not at all rare, needs special explanation. This is the so-called biochemical pregnancy. With her, the level of hCG first shows the presence of an "interesting position", and then belated periods come. What actually happens, it becomes clear if you know that the probability of blastocyst implantation is only about 30%.
Thus, even if fertilization has occurred, it is not at all a fact that the fertilized egg will successfully anchor in the uterus. In this case, the woman may not even know that she was pregnant.
How many such unreasonable delays ladies write off on nerves, stress, illness, climate change! And only a blood test for hCG, if for some reason it is recommended to undergo it during this period, even during menstruation will show an increased level of concentration of this hormone.
To exclude errors when passing the analysis for hCG, whether it is a blood or urine test, you should undergo repeated examinations only in the same laboratory that did the first analysis. This will eliminate significant errors in the diagnosis.
Often, women are completely unreasonably worried about a decrease in the level of hCG or its slow growth, if one analysis was done in one clinic, and the second one was done in another. Perhaps the reason is not in the level of hCG and pathologies, but in the difference in the work of two separate laboratories.
Does HCG fluctuation indicate fetal pathology? When is there a reason to worry? The answers to these questions are waiting for you in the next video.
