Test operation principle
Since the beginning of its existence, the future placenta begins to release a special hormone human chorionic gonadotropin (hCG). On its detection, that is, diagnosis in the urine, the principles of the action of pregnancy tests are based. They are designed so that they "notice" the necessary level of this hormone HCG in the woman's body by the appearance of two strips. From the physiology and characteristics of each woman depends on what day after the delay of menstruation can diagnose a pregnancy. The first day or the fifth is for every woman in her own way. After all, a certain level of this hormone is needed for diagnosis. It increases every day after conception. But on the first day after conception, the hCG level is still quite low. Therefore, to do the test immediately does not make sense: the result will not be seen. Depending on the quality of the tests, that is, their sensitivity, two planes may appear, starting from the 14th day after ovulation. This is the basis for the recommendation of doctors to do the test only after a delay, rather than earlier.
Why is the result false positive?
Firms-manufacturers of tests promise their reliability at the level of 90-99%. And yet, even expensive, sensitive tests can be wrong and in the absence of pregnancy show the long-awaited 2 strips. This is a false positive result. It happens and vice versa, when the pregnancy has come, the test does not diagnose it. Why is it so?
Sometimes the cause may be a wrong test, that is, a violation of the instruction. Probably, the test has exhausted its expiry date. The cause may be the presence of a woman in the body of a tumor that produces hCG, kidney disease. Also, the level of hCG decreases and "complicates" testing in case of threat of miscarriage. But stress, alcohol consumption, taking medication does not affect the test result.
Test Faith: Pros and Cons
The topic of reliability tests on forums is very popular. And many women share their experience of using tests. Some women talk about using the Vera test and a reliable result.
Among those tests, the results of which are doubtful and which should not be trusted, there is a test of Vera. Some women state that the test several times gave a negative result in the presence of pregnancy; others complain about the "weak" second strip, the third women are surprised that the test shows the presence of pregnancy even in the baby's urine. The tests of other manufacturers used simultaneously with Vera gave a negative result.
One of the women, who could not conceive for a long time, shared her method of testing the test Vera: she bought 3 tests at different pharmacies at the same time in the city. All gave a positive result in the absence of pregnancy. So she did 3 months in a row, the results were similar. After that, the lady laid out the experience with the cheating test on the forum.
Women should remember that the Faith test does not belong to highly sensitive tests. For confidence in the result, it is recommended to use tests from different manufacturers. If, for example, all three tests show a positive result (and with them, and Vera), then you can believe them. But best of all, instead of 3 cheap buy one inkjet test. Its reliability is much higher.