Treasured two stripes. But maybe it's too early to rejoice? There are times when the veracity of pregnancy test results is questionable. Perhaps, in our time, the first thing that women use to determine the onset of pregnancy is special test systems. Although most manufacturers say that their products are highly sensitive and therefore fairly accurate in detecting pregnancy, there are many cases where a pregnancy test produces false results. Christina Prishvina, gynecologist-endocrinologist, gynecologist-reproductologist, specialist in ultrasound diagnostics at the Lito Medical clinic (@lito_medical), member of the RARCH association, ESHRE, named Letidora the main reasons why a pregnancy test can have errors. What are the types of pregnancy tests? A pregnancy test can be produced in different formats. Here are the most common options for pregnancy tests. Test strips or strip tests These are quite convenient and, in fact, the simplest options among all pregnancy tests. They look like an ordinary paper-plastic strip with a reagent applied to it. The mechanics of the test are very simple: just place the strip in a container of urine. A few minutes after contact of the reagent with urine, you can wait for the results of the pregnancy test. The strip will stain in one or two zones, showing either no pregnancy or a positive result. Tablet tests (cassette) According to the principle of operation, they are the same as strip tests. But they determine the presence of pregnancy more accurately. Such tests rarely give false results. The likelihood of error is minimized due to dosing of urine, and also because the test has a limitation of the place of contact with a special window. A pipette is included with the test. It is worth reading the instructions for use, which explains how to use such tests correctly so as not to see false results. Using a pipette, you need to collect urine (dosed) and place it in the first window on the test. After a few minutes, you can watch the result. It will appear in another window: two strips or one - depending on whether you are pregnant at the moment or not. Inkjet tests These tests are considered the most convenient of all pregnancy tests. To obtain pregnancy test results, place the device under the stream of urine for about 10 seconds. After a few minutes, he may show the absence or presence of pregnancy. The main advantage is that the inkjet test does not require collection of urine in a container or pipette. Accordingly, such a pregnancy test can answer an important question anytime, anywhere. How these tests work Tests detect pregnancy by a chemical reaction that occurs when the test strip (with a special reagent applied to it) comes into contact with urine. This reagent reacts with human chorionic gonadotropin (hCG). This specific hormone begins to be produced at the moment when the embryo is implanted into the wall of the uterus. That is, the presence of human chorionic gonadotropin indicates that there is pregnancy. It is to this hormone that most all pregnancy tests respond. If you carefully study the instructions for use, you can find there a recommendation to carry out such tests a day or two before the expected period. During this period of time, the pregnancy test boasts the greatest information content.Some tests determine the presence of human chorionic gonadotropin two or three weeks after the expected day of conception. This is true for girls who have an irregular menstrual cycle. If you strictly follow the instructions for use and follow the recommendations for conducting, such tests are unlikely to show false results. Why the test may show false results However, there are several reasons why two stripes on the test can actually mean no pregnancy, and vice versa. False results happen for the following reasons. The woman was too hasty to carry out the test. In this case, the concentration of human chorionic gonadotropin in the urine is still insufficient. This situation is most likely to happen if conception happened almost before the start of the expected menstruation, and the hormone has not yet accumulated in the woman's body in sufficient quantity to react with the test reagent. Therefore, a pregnancy test may show a result that does not correspond to the true state of affairs. This refers to a situation where the test was not only performed too early, but also too late. With a period of more than 12 weeks, even a test with high sensitivity will be uninformative: during this period, the production of human chorionic gonadotropin stops. With an ectopic pregnancy and if there is a threat of miscarriage In these cases, a rapid test will show false results. This is largely due to the fact that the level of human chorionic gonadotropin decreases during an ectopic pregnancy (a blood test for hCG is prescribed in order to eliminate the problem). Also, low values of human chorionic gonadotropin may indicate cases when there is a threat of miscarriage, gestosis or intrauterine death. The woman has taken a lot of liquids The veracity of the results of a pregnancy test can be questioned if you have drunk a lot of liquids. It cannot be ruled out that the fluid diluted the urine and lowered the human chorionic gonadotropin concentration. Because of this, the test can show, for example, the absence of pregnancy, and not two strips. In order not to get false results, do not ignore the instructions for using the test, where it is often written that it is recommended not to drink a lot of fluids before performing all pregnancy tests. It is also advised to deny yourself the use of drugs containing components that have a diuretic effect. The woman did not perform the test in the morning. There are rapid tests with high sensitivity. If you study their instructions for use, you will find information that such tests can be performed at any time of the day. Still, I would not recommend doing the test at any time of the day or night. I advise you to use morning urine, especially in the early stages of a possible pregnancy. The chances of getting false results in this case are significantly reduced. Pregnancy tests can be false negative or false positive. In what other cases can a pregnancy test give an incorrect result A woman has taken medications aimed at stimulating ovulation When taking medications that stimulate ovulation, and for a couple of weeks after the end of their intake, a serious level of human chorionic gonadotropin remains in the urine. It is not advisable to conduct a test at this time. The woman has previously had miscarriages, abortions, ectopic pregnancy. In these cases, hCG is also stored in the blood. And accordingly, the test may be positive for some time. Pregnancy Frozen Early If this happens, one pregnancy test may be positive and the other negative. Often a woman does not even notice that there was a pregnancy and she froze, because everything goes like normal menstruation, but with a slight delay.In any case, if you are in doubt or the tests show different results, you need to contact a gynecologist and do an ultrasound scan to exclude pathologies. In this case, you will get the most reliable result. There may be tumor processes in the body. A pregnancy test may be positive in case of tumor processes. Therefore, be very attentive to your body, monitor your health and undergo preventive examinations on time. Especially if you have a genetic predisposition to cancer. The test was not of the best quality or expired. Such tests may show erroneous results. You should always check its expiration date and the tightness of the packaging. In this situation, you should not chase savings. This can play a cruel joke on you. The woman violated the rules for collecting urine and conducting the test. Instructions for use accompany each test for a reason. By following all the recommendations, you increase the chances of getting the most correct answer to the question - two strips or no pregnancy. Photo: Depositphotos; freepik.com Let's be friends on social networks! Subscribe to us on Facebook, VKontakte and Odnoklassniki!