When there is a positive pregnancy test
The basis of the pregnancy test is a reaction that reveals the hormone of hCG( human chorionic gonadotropin).It begins to be produced by the body of a woman one week after fertilization, after implantation, or the attachment of a fertilized egg to the uterine wall. Before the implantation of hCG in the body there, so it is impossible to determine the presence of pregnancy.
Types of tests
All tests for pregnancy are divided into three groups.
- Test strips. The principle of this test is as follows. In a clean glass container should be collected morning urine, because it contains the highest concentration of the hormone hCG.Then the test strip is dipped into the urine. On the surface of the test there is a control strip, and if a second appears next to it, this is a positive pregnancy test.
This assay method is not very reliable, because the indicator may not penetrate well enough with urine, and the result will be incorrect. Alternatively, if the test strip is depressed deeper than necessary, or kept in the urine longer than necessary, the error will be required. It is also possible to marry when manufactured, if the test strips are poorly impregnated with the reagent, for example. That's why such specimens are cheap enough. For the test test, repeat the procedure after 48 hours.
- Tablet Tests. They are more expensive than previous ones, and more reliable. These tests are used in hospitals for analysis. In his body there are two windows, in the first of which a drop of urine is applied, and in the second there is a result. In this case, a positive test for pregnancy is the acquisition of a colorless reagent color.
- Inkjet test. To date, this is the most reliable specimen for pregnancy. This type of test contains a special layer of particles that interact with the hCG hormone, provided it is present in the woman's urine, that is, in the case of pregnancy. Unlike other types of dough, this is substituted for a stream of urine, and does not drop into the reservoir, so it is quite convenient for use in any conditions and at different times of the day. The result will be ready in a minute after the procedure, and quite reliable. But the price of this test is correspondingly high in comparison with others.
There are also test systems with a built-in reservoir for urine, with a window for the result. The amount of urine in the tank does not affect the result of the analysis, since the system itself absorbs the required volume for the test. After waiting a little, the result will be displayed in the window.
Erroneous results of
Sometimes the test can produce an error. Maybe the test system was stored incorrectly, or the instruction was not followed during its execution. An error will also occur in the case of carrying out the test at a very early stage after fertilization, since the woman's blood and urine have a very small concentration of the hCG hormone.
Sometimes, very rarely, the content of hCG is increased due to the development of tumor processes in the organs of the reproductive system. In this case, the test will be positive, although pregnancy has not occurred.
Compliance with instructions is a guarantee that the result of the test will be as reliable as possible. The test strip should never be placed under a stream of urine, it is not intended for this purpose. The results should be evaluated only after a few minutes, but do not overdo it( in fifteen minutes or more, a weak double strip can appear on the test strip, which does not mean anything).A reliable result can be obtained within five to seven minutes, no more. Do not touch the reaction zone with your hands, and you must protect it from dirt and moisture. If the test expired - you need to safely throw it away, it is already bad.
The false negative result can be if all the test conditions were not met, or it was expired, or if the pregnancy period is too short. It is better to wait a week, and again to repeat the test.
A false positive pregnancy test can occur if a woman takes HCG-containing drugs. After the termination of reception of such preparations should pass not less than 14 days, differently the test will be erroneous. Or, if there is a high level of other hormones in the blood, which are very similar in structure to hCG, the test will also be false positive. This may be after the onset of menopause.
In addition, if the pregnancy has been interrupted, then within two to three weeks the test can also remain positive. So, under certain conditions, there can be both a positive test in the absence of pregnancy, and a negative test if it is available.
Can there be a positive test for ectopic pregnancy? Since the test responds to the appearance of a hormone produced by the body of a woman, regardless of the location of the fetus( in the uterus or in the tube), the result, of course, can be positive. But whether the pregnancy is ectopic or not - only a doctor can determine.