Can an HCG test be wrong

The most accurate method

Many potential mothers worry about whether the hCG test can be wrong? Doctors say with confidence: yes, an error, in general, can happen, but the accuracy of this method, as a rule, is 99 percent. It is even higher than the accuracy of the various tests women choose to determine pregnancy.

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A blood test for hCG is the most accurate way to determine pregnancy in the early stages. It is reasonable to carry it out just a few days after implantation of the embryo into the wall of the uterus. It is known that hCG begins its production in the female body only when a fertilized egg has already “glued” to one of the walls of the uterus.

Hormone of "interesting position"

Based on the above, it follows that the described hormone can be called the pregnancy hormone. If a woman still only suspects that she could become pregnant, there is absolutely no need to wait until her menstruation is delayed in order to carry out the test necessary in this situation. She will simply donate blood for hCG, and based on their results she will already understand whether she is waiting for a stork or not yet. This is a paid analysis. And blood is donated either at the antenatal clinic or at any of the private clinics located near the potential mother’s place of residence.

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Can blood hCG be wrong? Indeed, not all women trust the reliability of his results. But its accuracy is quite high (this was already mentioned a little higher). Of course, an absolute guarantee of the reliability of the result obtained is impossible when performing any analysis. We must not forget that there is a human factor. Can the laboratory make a mistake in hCG? Yes, there are quite rare cases when laboratory assistants make mistakes, but they cannot be ignored.

Error or not

When an analysis is performed, it is very important not only to do it correctly, but also to decipher the result obtained. Some of the doctors who perform such a study can tell about the onset of pregnancy just by seeing that the level of human chorionic gonadotropin in the woman’s blood is noticeably increased. But in reality, this approach is not particularly correct. To talk about the onset of pregnancy and that it is developing normally, it is better to conduct a couple of tests. The time interval between them is at least one week.

If a woman is really expecting a baby, then with each passing week the concentration of hCG in her blood will begin to grow and increase two to three times. If the gonadotropin remains unchanged, this may be evidence that the pregnancy is ectopic or it has frozen, unfortunately.

What is this analysis anyway?

In order to correctly answer the question of whether an hCG analysis can be wrong, you must initially understand the principle of conducting such an analysis.

Essentially, this is a regular blood test for hormones, which most women take many times during their lives. Human chorionic gonadotropin is produced in the chorion (the so-called outer embryonic membrane) after the embryo has attached to the wall of the uterus.

When a woman is in her normal state, that is, she is not pregnant, the level of the described hormone in her blood is approximately 5 mU/ml. By the way, the same amount is produced even in men as a result of the work of the pituitary gland (this is a special part of the brain).

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But when pregnancy occurs, the level of hCG in the woman’s blood begins to increase. At first this happens exponentially, and then it decreases almost as quickly. In the second half of pregnancy it remains almost at the same, almost unchanged level.

Can hCG make mistakes? This is an important question for women. Based on the level of this hormone, the analysis will be able to determine whether pregnancy exists or not, whether there are any kind of fetal pathologies or not. It is by analyzing hCG that they determine how pregnancy develops.

By the way, it is this hormone that women owe to the correct course of the entire pregnancy, because how the expectant mother will live for the next nine months directly depends on its level. Due to the fact that the level of the hCG hormone increases, menstruation is “frozen” and there is a significant increase in the production of hormones that are so necessary to maintain each pregnancy.

The hCG hormone has alpha and beta subunits. The alpha subunit is similar to other human hormones; but the beta subunit is unique in its own way: it is a marker of the presence or absence of pregnancy.

Causes of a false negative result

In order to correctly answer the question of whether an hCG analysis can be wrong, you must initially understand the principle of conducting such an analysis.

When a woman is in her normal state, that is, she is not pregnant, the level of the described hormone in her blood is approximately 5 mU/ml. By the way, the same amount is produced even in men as a result of the work of the pituitary gland (this is a special part of the brain).

This analysis is highly accurate. At the same time, the human factor cannot be excluded, since the person conducting the research may make a mistake. However, situations where laboratory assistants made a mistake are rare. Doctors often interpret a positive test result as evidence of pregnancy, which is not entirely correct.

For an accurate result, it is better to donate blood several times (about once a week). In a pregnant woman, the amount of hCG will increase 2-3 times with each analysis. If the concentration of human chorionic gonadotropin remains at the same level, this may indicate an ectopic or frozen pregnancy.

Human chorionic gonadotropin is found in the blood of all people. However, in pregnant women the level of this hormone is 2-3 times higher than in non-pregnant women.

An incorrect test result with a low hormone content may occur in the following cases:

Pregnancy is too short. Blood tests for hormones have a certain degree of sensitivity to gonadotropin. Typically, the required concentration of the hormone appears only by the 5th day of a missed period. Before this period, most tests will not show pregnancy. There are some studies that determine the presence of a fertilized egg in the uterus already on the 10th day after conception. They can be performed on 1 day of missed menstruation. But before this period, pregnancy cannot be detected, since the amount of hCG in the blood is too low.
Pathological course of fetal development. If the pregnancy is ectopic, or there is a threat of miscarriage, then a very small amount of the hormone is produced and it cannot be determined.
Placental insufficiency or weak implantation of the fetus to the uterine wall. In these cases, the body produces very little human chorionic gonadotropin, so the analysis is not able to detect pregnancy, despite its presence. The same result is possible with late attachment of the embryo to the walls of the uterus.

We suggest that you familiarize yourself with: HCG, how long does it take to perform an analysis?
The hCG test can also make mistakes in cases where too much human chorionic gonadotropin is formed in the body of a non-pregnant woman. This is a serious hormonal disorder. Then a blood pregnancy test may give false positive results.

High levels of this hormone can be observed with pituitary adenoma. Typically these tumors are hormonally active. Those who have adenomas often suffer from endocrine disorders, which lead to an increase in gonadotropin. In this case, the hormone is produced not by chorion tissue (embryonic membranes), but by pituitary cells.

False test results and elevated levels of human chorionic gonadotropin, not associated with pregnancy, can be observed with malignant tumors. An hCG test is often a tumor marker. An increase in gonadotropin may indicate the following diseases:

mammary cancer;
lungs' cancer;
ovarian cancer;
stomach and liver cancer.

In addition, an increase in the hormone can indicate tumors such as chorionic carcinoma and hydatidiform mole. Chorionic carcinoma is a tumor of the uterus that forms after a previous pregnancy. In this case, chorionic villi remain in the uterus, which then degenerate into a malignant formation. Chorion particles can continue to produce hormones.

Hydatidiform mole is a pathology of pregnancy that begins in the early stages. Due to incomplete fertilization of the egg, tissue in the form of bubbles grows in the uterus instead of the placenta. The embryo dies, but the pathological formation grows and continues to produce the hormone.

This suggests that an increase in human chorionic gonadotropin not associated with pregnancy may indicate serious pathologies that require urgent treatment.

Of course, a false positive test result does not always indicate tumors and other dangerous diseases. Most often, an increase in human chorionic gonadotropin is associated with hormonal imbalance. In middle-aged women, this hormone increases during the period before menopause.

A false test result may occur in a woman who has recently undergone an artificial termination of pregnancy. In this case, the hormonal levels have not yet returned to normal.

The test result is incorrectly defined as positive when ingesting or injecting drugs containing human chorionic gonadotropin. These drugs include:

Profasi;
Decayed;
Human gonadotropin;
Human chorionic gonadotropin;
Choriogonin;
Horagon;
Ovitrel.

These drugs are quite often used in the treatment of infertility and before the IVF procedure, so the likelihood of an error due to taking the medication is quite high. If the patient has undergone a course of therapy with such drugs, the laboratory assistant must be informed about this. Other medications, including hormonal contraceptives, usually do not distort the results of a pregnancy test.

You should know what to do if the blood test result gives positive or negative results that are in doubt.

Additional research can also be done. For example, take a urine test for human chorionic gonadotropin. You can use a two strip test. Ultrasound can help confirm or refute pregnancy. It shows gestation at 5-7 obstetric weeks.

If pregnancy is not confirmed by any other tests, but human chorionic gonadotropin in the blood continues to remain high, the patient must undergo a comprehensive examination. You should contact an endocrinologist, gynecologist, mammologist and oncologist. You need to undergo a series of tests that will reveal the function of the pituitary gland and ovaries. In addition, the doctor may prescribe a pelvic ultrasound and mammography.

We suggest you read: Throws you into a fever during pregnancy

A high level of gonadotropin production in a non-pregnant woman may be the result of a temporary hormonal imbalance. But sometimes this can indicate serious illnesses that require treatment. In addition, a large amount of this hormone does not leave its mark on the body. Elevated levels of hCG lead to the appearance of luteal cystic formations in the ovaries.

How does hCG normally rise?

Before you figure out whether hCG can be wrong for pregnancy, you should understand: if the pregnancy develops absolutely correctly, as it should be, then the level of gonadotropin will constantly “grow” until the tenth or twelfth week. Then it starts to decline. This has already been mentioned a little higher.

The change in hormone levels in each expectant mother occurs completely differently, so you should not rely on any established norms for its growth. Still, in most cases, gonadotropin levels double on average every one to three days by the fourth week, and later every three and a half days by the ninth week. It is considered absolutely normal that hCG falls after the tenth to twelfth week.

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If there is no increase or decrease in hCG levels, the woman should immediately contact her gynecologist, because this may be evidence of a miscarriage or that the pregnancy has stalled.

If a reverse reaction is observed, that is, the level increases quite quickly, then you should also go to an appointment with a gynecologist, because this is the only way to eliminate some complications, for example, hydatidiform mole.

Features of the analysis

How to take an hCG test for pregnancy? To do this, a woman needs to come to the biomaterial collection office with a referral. Afterwards, the laboratory assistant will fill out the relevant documentation and ask you to sit in a chair. Blood will be taken from the veins.

For the test to show a reliable result, you need to go only on the 4th day of absence of menstruation (taking into account that they previously came regularly). To clarify the result obtained, you can donate blood again after a couple of days. If you know exactly the day when conception should have occurred, then it is advisable to visit the laboratory office 6-7 days after that.

There are urgent analyzes and those performed during normal operating hours. The first option involves additional material investments on the part of the patient.

Medicines that affect the level of hCG in the blood

Many women are worried about whether hCG can make mistakes before the delay? Especially if they were taking certain medications. Here you need to know one more thing: the level of hCG in the blood is changed only by those medications that contain this hormone (Choragon, Pregnil). Such medications are usually used by women who are being treated for infertility when it is necessary to stimulate ovulation. If you have taken one of these medications or a woman has taken a certain course in order to stimulate ovulation, you must inform the laboratory technicians in the laboratory where she will be tested.

Can a blood test for hCG be wrong? It should be understood that no other medicine is able to distort (that is, increase or decrease) the results of a blood test for hCG. Birth control pills also have absolutely no effect on the results obtained after taking a blood test for hCG and on the results of a pregnancy test.

Incorrect positive hCG test

Except for cases where, according to all signs, a woman is expecting a child, but the result of a blood test does not confirm this, a situation may arise when the hCG test is positive, but the test does not show pregnancy. And again the question arises, can the hCG analysis indicate an “interesting situation”, but the test cannot?

Most often, in such cases, the analysis determines the presence of pregnancy in its actual absence (those scenarios where the home test strip turned out to be defective do not need to be taken into account). This situation can arise for various reasons:

The woman was taking hCG-based drugs to treat infertility;
The body itself began to produce more of the hormone;
Tumor formations;
Choriocarcinoma;
Substances similar to hCG in their composition and properties were found in the blood.

In case of treatment using hCG, you need to wait several days until the hormonal levels return to normal. If during the examination the woman did not find the above diseases or anomalies in the body, then the result may not be erroneous. But this can only be confirmed by donating blood again.

Despite the possibility of obtaining an incorrect hCG test result, modern medicine has not yet invented a way to more accurately determine whether conception has occurred. That is why you should not put off a visit to the laboratory for a long time, since monitoring the dynamics of the hormone level will help detect abnormalities in the development of the embryo when this can still be prevented.

Bibliography

Emergency care in obstetrics and gynecology: a short guide. Serov V.N. 2008 Publisher: Geotar-Media.
Arterial hypertension in pregnant women Preeclampsia (preeclampsia). Makarov O.V., Volkova E.V. RASPM; Moscow; TsKMS GOU VPO RGMU.-31 pp.- 2010.
Gestagens in obstetric and gynecological practice. Korkhov V.V., Tapilskaya N.I. 2005 Publisher: Special Literature.
Emergency conditions in obstetrics. Sukhikh V.N., G.T.Sukhikh, I.I.Baranov et al., Publisher: Geotar-Media, 2011.

Strange changes

Can HCG make mistakes? Most likely, the person conducting the analysis may make a mistake. The human factor should not be excluded in this situation. The possibility of error is quite small. It is quite rare for a laboratory worker to confuse two samples of biological material or misinterpret the results of an analysis.

If the increase in gonadotropin concentration in the blood stops, this may indicate a threat of spontaneous abortion.

Can hCG make mistakes in the early stages? A woman should understand that a false negative result is possible if she contacts the laboratory too early to get tested. Doctors suggest donating blood at least a week or even ten days after the date of expected conception. And to increase the accuracy of the analysis, it is taken on an empty stomach in the morning.

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If a woman is too worried about whether hCG can be wrong in the early stages, she doesn’t have to do such an analysis, but just purchase a test at the pharmacy. This strip should be dipped in urine for a few seconds, and then, after just twenty seconds, evaluate the result. If there is an increased concentration of hCG in the urine, the test will show two notorious lines.

Only a doctor can determine more accurately whether pregnancy has occurred or not, after conducting a medical examination. A woman should not run to the laboratory to do various tests and diagnose herself. The doctor will refer the patient for tests if they are necessary.

But can hCG make mistakes in the early stages? Yes, this can happen. Sometimes it happens that the test result is negative, but the woman has some kind of concern. In this case, she can donate blood again after waiting one or two weeks. This way all suspicions will be removed. If the woman is not mistaken and she is really expecting a baby, then during these two weeks the concentration of the hormone in the blood will have time to increase.

Can hCG make mistakes in early pregnancy?

Yes, the test results may show a false negative result. Such an error is possible if the woman donated biomaterial (blood, urine) for analysis too early, when less than 5 days have passed since conception. In this case, a false negative hCG test result is obtained.

In order to accurately select normal values for each patient, it is necessary to know the gestational age, accurate to the nearest week. However, an isolated study on the value of human chorionic gonadotropin is not enough to definitively establish the fact of pregnancy. An additional ultrasound examination should be performed.

If the possibility of pregnancy is clearly excluded, a comprehensive diagnosis is urgently carried out. Since there is a high probability of developing a malignant tumor in the body, which is the source of hormone-like substances.

Exceptional cases should be highlighted separately. According to statistics, approximately 2% of women have high levels of analysis for human chorionic gonadotropin. The reason for such false-positive data most likely lies in a violation of the patient’s hormonal status or oncopathology.

Situations cannot be excluded when pregnant women have a negative result for hCG. The phenomenon is explained by late implantation of the embryo or ectopic pregnancy.

Proper preparation for analysis

In order to reduce the risk of erroneous results, attention should be paid to the preparation rules. Biomaterial is handed over from 8 to 10.00 am, 8-12 hours after the last meal. Biomaterial collected from the patient 4 hours after taking a light snack can be accepted for analysis.

The liquid can be consumed in unlimited quantities before taking biomaterial. It is important that it is not sweet and without gas. This will help make it easier to perform venipuncture and collect enough blood for testing.

You will have to give up sports training 1 day before visiting the laboratory department for the purpose of hormonal diagnostics. Because physical activity, along with emotional stress, stimulates the activity of the glands of the endocrine system. This may result in unreliable results. For the same reason, alcohol and smoking are not allowed 3 hours before taking biomaterial.

Two days before the test you should avoid drinking alcohol.

Read further: How to properly donate blood for sugar from a finger and vein, how to prepare for donation

Pregnant or not

Can hCG make mistakes a week in advance? This is also possible, although not necessary. This was mentioned a little higher. You should also know that if the concentration of hCG in a woman’s blood increases, this does not necessarily mean that she will become a mother in the near future. This may indicate that tumors are developing in her body - benign or malignant. Because of this, hCG levels sometimes increase in men.

By the way, women experience an increase in gonadotropin concentration if they are currently using hormonal pills (in this case, the analysis will not be sufficiently informative) or have recently had an abortion.

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Now let's look at an ordinary situation. In men and women who are not pregnant, the concentration of hCG usually does not exceed 2.5-5 mU/ml. But after a whole week has passed since the implantation of the embryo into the wall of the uterus, the indicator will already be approximately 100-350 mU/ml. Until about the twentieth week of the “interesting situation,” the concentration of gonadotropin in the woman’s blood will increase, and then gradually decrease.

Can HCG make mistakes? The accuracy of this analysis is quite high and the likelihood of errors occurring after misinterpretation of the result or incorrect implementation is minimal.