You know exactly when you have dangerous (or vice versa desirable) days, but one day the test will show you a different result than you expected. Can a pregnancy test be wrong, and what could be the reason for this? In the material you will find the five most common mistakes that can give the wrong result.

And some are waiting

The complete opposite of the previous point, there are those who wait too long to receive their test results. This often happens when a woman takes a test early in the morning, then quickly jumps into the shower, and then proceeds to check the result. The instructions usually indicate that the test result is visible for no longer than 5 minutes.

After this, the test may continue to work and the strips will indicate a weak but positive result when in fact no hCG was detected. Don't be tempted by the thought of reading anything on your pregnancy test the next day or after you fish it out of the trash many hours later.

Distrust of a positive pregnancy test result

False positive test pregnancy is extremely rare. The most common causes of pregnancy test errors are due to user error rather than the test itself.

If you have a pregnancy test that says there are two lines, then you have to believe and understand that you are pregnant and act accordingly. It is even more likely that you will subsequently have a chemical pregnancy or a very early miscarriage than that the positive result was a mistake.

If you have a sufficient level of hCG, then the test will be positive in any case, but no one is safe from a miscarriage soon after.

Every woman planning a child will be interested to know whether the test may not show pregnancy. If your health is good, no drastic changes have occurred recently, and you got a valid test, then there shouldn’t be an error. However, life is not the most stable thing, and circumstances do not always coincide well. Therefore, samplers can indeed make mistakes. But in what cases?

Test and its use

Marriage

No factory can guarantee 100% serviceability of its products. Manufacturers of pregnancy tests are no exception.

Such products can be easily damaged during transportation or storage. Often mothers themselves violate instructions. Increased air humidity, temperature changes, impacts on a hard surface - even individually, these are enough to make the test unusable. Another common reason is expired. To avoid getting into an unpleasant situation, it is better to immediately remember a few simple rules:

• buy tests only in pharmacies (not in markets or online stores);
• check the production date immediately, before calculating the purchase;
• throw away old samples purchased the year before;
• pay attention to appearance products - the presence of cracks, stains, bends and similar defects;
• read the storage rules described in the instructions;
• do not trust the cheapest tests;
• For reliability, use several products from different brands.

Violation of operation

Often women are so worried about the result that they do not consider it necessary to read the instructions for use before starting the procedure. This approach often ends up with a false indicator. The most common mistakes:

• overexpose or, conversely, do not keep the test in the urine long enough;
• completely dip the probe into the container with urine or wet only the edge of its tip;
• touch the indicator with your fingers, wipe it, touch the toilet with it, or do something like that;
• shake the test to “speed up” getting an answer, carry it with you instead of putting it on a flat surface and wait;
• use the same product more than once;
• turn over and hold the body with the tip up, not down (for inkjet and electronic);
• focus on the result after the waiting time specified in the instructions (after an hour or even a day, the strip may disappear/appear).

Reading the instructions is not a convention, but a necessity, especially since the instructions for different tests can differ radically.

Inappropriate urine

Most tests require exactly morning urine, especially on early stages. In the daytime or evening, the concentration of hCG, the “pregnancy hormone”, to which product indicators react, decreases. A test done in the afternoon will not be reliable.

Urine can be stored in the refrigerator for 24 hours, tightly closing the jar with this substance. At room temperature, after just a few hours the liquid loses some of the properties necessary to determine pregnancy.

Another problem is the presence of organic substances in the tested urine. If the container with it was in a dusty place or it itself was not clean, this will also be reflected in the indicators. Even water getting into the container can distort the actual result. It is very important to ensure that the container is sterile and dry before use.

You should not eat or drink before the procedure. It also affects the level of hCG in the blood and urine.

Late use

Even the most sensitive tests will not show pregnancy earlier than 7-10 days after intercourse. To be sure, it is better to wait for 1-3 days of delay and then go through the procedure.

Inkjet tests are usually the most sensitive. And yet, the main indicator of increased susceptibility of the indicator to hCG is the 10 mIU/ml mark on the package. Such a product can detect pregnancy even a couple of days before the delay. The rest begin to show correct results only after a couple of days of absence of the expected menstruation.

Cycle Features

Late ovulation

As a rule, ovulation occurs approximately in the middle of the menstrual cycle. However, sometimes it shifts by several days. In women with a regular cycle, the egg may be released 1-3 days later. For those whose menstrual schedule is irregular, ovulation is sometimes delayed by a week. In rare cases, it occurs even on the first day of menstruation. However, a delay in the ovulatory process for more than 10 days is considered pathological and indicates health problems.

If ovulation actually occurred later than usual, the test will begin to show correct results at approximately 5-7 days of delay.

Delayed implantation

Normally, transportation of a fertilized egg to the uterus and attachment of the embryo to its wall takes 7-10 days. But sometimes failures occur, then the whole process takes even more time.

It is fair to say that such cases are quite rare and are not considered a common cause of “late” pregnancy.

Hormonal disbalance

Stress, illness, changes in climate, diet, and activity cause hormonal imbalance. And while the woman’s body tries to cope with the raging hormones, the test will begin to show uncertain results:

• one day - positive, another - negative;
• false positive;
• false negatives;
• indeterminate, when the second stripe is barely visible;
• Some tests show pregnancy, some do not.

Anomalous processes

Diseases of internal organs

The body is a single system. If one organ does not function properly, it will affect other parts of the body. The test will most likely not show pregnancy if a woman has serious or chronic problems with:

• heart;
• vessels;
• kidneys;
• pituitary gland;
• urinary tract.

These complications inhibit or greatly reduce the production of hCG. An increased amount of protein in the urine also distorts the performance of pharmacy tests.

Pathology

This category of cases may be completely asymptomatic, but that is why it is dangerous. If a woman has had unprotected intercourse, and the tests stubbornly show one line, she should definitely see a doctor. Especially if she begins to feel severe or sharp pain, notice unusual discharge or an increase in temperature above 37.5 ° C. Possible reasons:

• ectopic pregnancy (often tests still show no results);
• frozen pregnancy;
• risk of miscarriage;
• abnormalities in fetal development;
• problems with the formation of the placenta;
• incorrectly or poorly attached embryo.

In order not to be tormented by guesses whether the test may not show pregnancy, if the results are questionable, it is highly advisable to visit a gynecologist. A doctor and a laboratory test for hCG will determine what a pharmacy test cannot show. It is better to secure yourself with expert advice than to suffer from ignorance and uncertainty.

Tests to determine pregnancy are affordable and in a simple way diagnosing conception at home. These days you can purchase a rapid test at any pharmacy or supermarket. But the test result is not always accurate: sometimes the doctor does not confirm the presence of pregnancy, or, on the contrary, it is there, but the test shows a negative result. Are pregnancy tests wrong and how to avoid this inaccuracy?

It is unlikely that in our world there is at least one error-free device, system or equipment - all of them, due to certain factors, have a percentage of errors and can make mistakes. This also applies to rapid tests that women use on their own. Pregnancy test errors are possible, and this will be discussed in our article.

After conception, the fertilized egg implants into the wall of the uterus. From this moment on, the hormonal levels in the woman’s body change. The rudiment begins the production of human chorionic gonadotropin () - the pregnancy hormone. After a few days, the presence of this hormone is detected in the blood, and a little later in the urine. The purpose of a pregnancy test is to detect hCG in a woman's urine.

A certain part of the device is coated with a substance that, upon contact with urine, reacts to the presence of human chorionic gonadotropin. If the hormone is present in the proper amount, a reaction occurs and a coloring component appears, indicating the presence of pregnancy. In this case, the woman sees an additional (second) line on the test strip or in the results window.

If there is no hCG in the urine or its concentration is too weak, the pigment will not appear. The test will show a negative result or one control line.

Why do mistakes happen?

Sometimes even high-quality pregnancy tests carried out according to the instructions give an erroneous result. Why is this happening? It turns out that there are many factors that influence the correctness of the answer. According to experts, diagnostic results can be false positive and false negative.

Reasons for a false negative test:

1. The diagnosis was made too early, long before the missed period. Even ultra-sensitive test systems can give reliable results no earlier than 2-4 days before the expected menstruation.
2. in this . In this case, possible conception will occur somewhat later than expected. Even if the test is done in the first days of a missed period, the hCG level will still be insufficient for a positive result.
3. Use large quantity water or diuretics on the eve of diagnosis. Weak urine concentration reduces the reliability of testing.
4. Pathological pregnancy: , . In this case, it will enter the urine an insufficient amount hCG, and the test may show a questionable and even negative result.
5. Kidney diseases that prevent the growth of normal concentrations of hCG in the urine.

Reasons for a false positive test:

1. The presence of hormone-producing neoplasms in the body. There are tumors that synthesize hCG. They can be localized in the kidneys, uterus, stomach, etc.
2. Treatment with hormonal drugs containing hCG. For example, conservative treatment of infertility with the drug Pregnil, etc.
3. Transferred in the recent past artificial or.

How can you tell if the test is wrong?

It is impossible to say for sure that the test was wrong or showed the truth. Therefore, experts insist that any study must be rechecked after 48 hours. If two or three tests in a row show that there is no pregnancy, it is necessary to consult a doctor.

You should also visit a gynecologist if the diagnostic result is positive. In both cases, the specialist performs an ultrasound, based on the results of which final conclusions are drawn.

How to avoid mistakes

Even the most sensitive test can be wrong. First of all, expired products can fail. Therefore, when purchasing, it is important to pay attention to the expiration date and storage conditions of the rapid test. It is better to purchase the product at a pharmacy.

When choosing a test, pay attention to the manufacturing company. Popular large manufacturers are unlikely to produce untested defective devices.

Cheap tests are made from inexpensive and low-quality materials. Therefore, the result of the study may be questionable. The absorbent part of a cheap rapid test can get wet and shift towards the coloring pigment, indicating the presence of pregnancy. As a result, the woman will mistake this result for pregnancy.

Pregnancy test errors can also occur if the device is used incorrectly. For example, if this is due to a violation of the time the rapid test indicator remains in the urine. If the time for immersing the indicator in the biological fluid is not observed, it simply will not have time to become saturated with it, and the research result will be erroneous. An error can also occur if you overexpose the indicator in urine or immerse it above the established limit.

To avoid mistakes, the express test must be used according to the instructions. Failure to follow the recommendations for use may distort the diagnostic result.

Which tests are considered the most accurate?

There are three main groups of tests: test strips, tablet and inkjet devices.

Test strips are the most popular. The principle of their operation is simple: the indicator is lowered into a small amount of urine, and after 5 minutes the result can be assessed. The coloring of the second strip means that the test is positive; the absence of pigment coloring indicates the absence of pregnancy.

Sometimes the second stripe is barely noticeable, and such a result is considered weakly positive. In this case, it is recommended to repeat the diagnosis after 48 hours.

Test strips are less reliable. Inaccuracy may be due to low-quality materials from which the system is made, and violation of the instructions - such a test can be easily overexposed or underexposed to the collected urine.

Test systems in the form of a tablet are more expensive, the quality of their results is higher, but the principle of operation is the same as test strips. The device includes two windows: urine is dropped into one of them using a pipette, and the result is read in the other.

Inkjet tests are considered the most accurate. Some inkjet test systems determine the presence of pregnancy 4-5 days before the expected delay. In addition, they are convenient to use - there is no need to collect urine, and diagnostics can be carried out at any time of the day. Errors when using inkjet tests are practically eliminated.

In any case, experts recommend rechecking the test result 2-3 days after the test. It is advisable to use a test system from another manufacturer for this purpose. Whether pregnancy tests can be wrong is a controversial issue. If the test is chosen correctly, its expiration date has not expired, and the diagnosis is carried out according to the instructions at the appropriate time, the likelihood of an error is minimal.

Useful video about using a pregnancy test

Instructions

It should be noted that tests can go both ways, producing both false and false negative results. It is best to buy several tests at once from different manufacturers and use them several days apart; moreover, if you have the slightest doubt, you should consult a doctor.

The most common reason for a false result is a test done too early. Most modern remedies promise a guaranteed result from the first day of the delay, however, unfortunately, in the first days, tests show the correct result with an eighty percent probability; it is at this time that the probability of getting a false negative result is high, since the concentration of the hCG hormone in the urine at this time can be not high enough yet. To guarantee the correct result, it is better to test after four to five days and in the morning.

Drinking too much fluid in the evening can lower the concentration of hCG in your morning urine, so if you are going to test in the morning, try not to drink too much in the evening.

A false result may be due to poor quality of the test or an expired test. Expired tests or tests that were stored in the wrong place can result in completely unexpected results, so buy similar products in trusted pharmacies and from well-known manufacturers.

In some cases, erroneous tests may be due to improper use, so it is very important to read the instructions carefully and not shorten the waiting time required for the chemical reaction.

Sometimes the test strip may be too pale, in which case you need to use a different test, and you should also read the instructions again, you may have done something wrong.

If you are taking vasoconstrictors or hormonal drugs, diuretics or tranquilizers, this may distort the test results due to “wrong” hormonal levels.

In some cases, the first test may show the presence of pregnancy, and a second test taken a little later may indicate its absence. In such a situation, you should immediately consult a doctor, since such results may be signs of a miscarriage.

note

A false positive result can be obtained in the case of ovarian dysfunction and a number of other diseases of the reproductive system.

An express pregnancy test is not a replacement for a visit to the gynecologist, but it allows a woman to clarify the situation to some extent and clarify what exactly she will go to the doctor with. However, such tests are not always accurate.

A low-quality test or one that has expired cannot give a reliable result. You must be extremely careful when purchasing rapid tests, and you should not skimp on them.

The error may be due to incorrect application of the test. For example, if the strip is not used immediately, but is left in the air for some time, the substance that is applied to it will dry out and the test will become unusable. To avoid such mistakes, you need to carefully follow the instructions on the packaging.

But in some cases, errors in rapid tests are explained by changes in the woman’s body.

Negative result if pregnant

The rapid test reacts to human chorionic gonadotropin. The concentration of this hormone in the urine decreases and becomes insufficient for a positive result if the amount of urine excreted increases. This can happen if the woman has eaten any diuretic foods (such as watermelon) or taken a diuretic drug.

If a woman's cycle is disrupted, ovulation could occur later than usual. In this case, even if it has occurred, it has not yet had time to call the appropriate hormonal changes by the time the woman noticed the delay. If you repeat the test a week later, the result will be positive.

The concentration of human chorionic gonadotropin decreases with certain pathological variants course: threatened, frozen or ectopic pregnancy. Such cases require immediate medical intervention.

Most test manufacturers claim that the accuracy of rapid tests performed using their products is 95-98%. Currently, there are several types of test strips. The most expensive, but at the same time the most accurate, are inkjet tests.

The principle of operation of all products for early diagnosis of pregnancy is the same. Manufacturers impregnate the strips with special reagents that can react with human chorionic gonadotropin. The level of hCG in the urine begins to rise immediately after the embryo attaches to the uterine wall. Every few days, the concentration of the hormone in biological fluids increases approximately 2 times.

In order for a reaction to occur, the test strip must be lowered into a container of urine to the specified level. Its holding time is usually 20-30 seconds. More detailed recommendations can be found in the instructions written by the manufacturer. Most often it is found in a package with dough.

What happens if you overexpose a pregnancy test in your urine?

Improper use of the test may result in a false result. For example, if you hold it in a container with urine for more than 20 seconds, stripes may not appear on it at all. This is due to the fact that with prolonged exposure to biological fluids, reagents may be partially or completely washed out. After washing out special substances, the test is not suitable for use, since it will no longer contain reagents that can react with human chorionic gonadotropin.

Experts assure that if the test strip is left in the urine for too long, it is also possible to obtain a false positive result. Some expensive products for carrying out express pregnancy tests are made so well that the destruction of the reagents is impossible even with prolonged contact with urine.

As the exposure time of a high-quality test strip in a biological fluid increases, the amount of hormone that reacts with the reagents increases. This means that the second stripe may turn pinkish even if you are not pregnant.

A pregnancy test is a convenient invention that allows a woman to find out about her situation long before visiting a doctor. The result obtained at home will help you find out about the presence of pregnancy, provided that the test is used correctly.

Express diagnostics has a number of features that also depend on the type of device.

The principle of operation of any test to determine whether conception has occurred is similar - it is a reaction to the content of a special hormone in a woman’s urine - human chorionic gonadotropin. It is called hCG for short, and the body begins to synthesize it after the fertilized egg attaches to the uterine lining for further development.

That is, a positive pregnancy test can only be seen after conception has occurred.

An important question for many women is when to take a pregnancy test. It should be taken into account here that in the first days after conception the amount of hCG in the urine is minimal, but these figures increase every day. To get an accurate result as early as possible, it is better to donate blood from a vein to the laboratory in the early stages of the intended pregnancy. This way, the result can be obtained approximately 5 days earlier, before the test shows two stripes. And even a barely visible second stripe in the first days after conception makes women doubt.

Instructions

The instructions for the pregnancy test are something that you must read. After all, the accuracy of the result depends on the correct use of the device. Much depends on the type of rapid test, of which there are several.

Strip test (or test strip)

An inexpensive and most common device in the form of a paper strip with a reagent applied to it. There are usually no questions about how to use it. Morning urine must be collected in a clean container, lower the strip for about 10-15 seconds, and place the test on a dry surface.

The result will appear in a few minutes. Here, too, everything is simple: one stripe - there was no conception, two stripes - conception did occur.

Tablet

The principle of the device is similar to the previous one, only the paper strip is located in a plastic body. When is the best time to take this type of pregnancy test? Also in the morning. Only here you need to use the attached pipette to drop morning urine onto a special window in the device. The result is also assessed by the number of stripes.

Jet

Probably the most convenient device, it does not require urine collection. To obtain the test, you need to place it under a stream of urine and not necessarily in the morning, since tests of this type are more sensitive.

The result is the same stripes again - two or one.

Electronic

If you choose an electronic pregnancy test, the price will be significantly higher than a simple test strip. But the result should be expected to be as accurate as possible.

The kit includes a sample receiver, which either needs to be held under stream of urine or placed in a container with the collected liquid. The difference with other types of devices is when the results are shown. The result should be assessed after 3 minutes. The result is “+” or “-”, which respectively means the presence or absence of pregnancy.

When to do it?

It is best to take urine in the morning for testing. The reason is that it contains the highest concentration of substances, including.

But jet-type tests can be done at any time of the day due to their higher sensitivity. They indicate 10 mIU/ml.

Before the delay

The test result depends on the hCG content in the woman’s urine. The amount of the hormone increases every day. Will the test show an accurate result before the delay? Here again everything depends on the sensitivity of the device. Some of them, and, as a rule, the most expensive ones, are able to determine the presence of pregnancy 7 days after the expected conception, that is, before.

But already a week after the delay, any test can show probable conception, since the level of hCG is already quite high.

Could the result be wrong?

Whether a pregnancy test can be wrong depends on the device itself. Manufacturers, as a rule, indicate on the packaging an accuracy of up to 95 - 99%. This means there is 1 - 5% left for an incorrect result.

The reasons for a false negative result may be the following:

• testing was carried out very early, so the content of hCG in a woman’s urine is not enough to determine;
• incorrect testing (you should read the instructions);
• a device with an expired expiration date was used (this must be checked upon purchase);
• drink a large amount of liquid on the eve of testing (urine becomes less concentrated, which means the amount of hCG decreases).

If the test is false positive, the reasons may be:

• reception by a woman medicines in the treatment of infertility (these are usually injections that contain the hCG hormone);
• little time has passed since the miscarriage or premature birth (remnants of the embryo may remain in the uterus);
• the presence of malignant neoplasms.

It is worth mentioning that very weak second stripe. If it is, then there is a pregnancy, but the hCG content in the urine is still too low.

If you have doubts about the test result, you should repeat it again after three days. During this time, the amount of hCG will increase, and the second band will appear brighter.

For ectopic pregnancy

The test at will have . After all, almost the same thing happens in the body as during normal pregnancy, with the exception of the place of attachment of the embryo. The egg is fertilized, the embryo develops, and therefore hCG is produced in the body.

It is important to recognize ectopic fetal development in time to avoid dangerous consequences. Its arbitrary interruption usually occurs at 7-8 weeks, which is accompanied by severe pain and bleeding.

An ectopic pregnancy can be suspected if there are symptoms such as nagging abdominal pain and spotting with a positive test. If there are such signs, you should immediately consult a doctor.

To confirm an ectopic pregnancy, an ultrasound will be performed and a blood test for hCG will be taken. Here, the dynamics of the hormone content is taken into account, since during ectopic development of the fetus, the hCG content in the blood is lower than normal.

What will the test show? If during the first test there were two clear bands, and after some time the device shows a negative result, there will be a suspicion of fetal freezing. This diagnosis can only be confirmed by a doctor after an examination.

What to do if a woman sees a positive pregnancy test depends only on her. Some will be upset, but for others this will be the most desirable result. Expectant mothers can only wish them peace of mind, less nerves, and adhere to healthy image life and eating right. And, of course, it is necessary to make a visit to the doctor as early as possible for examination and to receive important recommendations.

Video about proper use