Many women have a pregnancy test in their home medicinecabinet , while others buy it with some frequency if they notice a delay in menstruation.
Thanks to the plentiful amount of information about the “two stripes”, many people know that on a pregnancy test it means a positive result, that is, that the woman is pregnant. But is this always the case? How does this test work, can it fail?
There are many tests for rapid diagnosis of pregnancy, but the principle of operation is the same for all – the detection of the hormone HCG (human chorionic gonadotropin) or, as it is also called, the pregnancy hormone. HCG is formed in women at the onset of pregnancy – it is released by the fetal membrane in the uterus.
Most often, a paper text is used, which is a litmus that helps detect the presence of hCG in a woman’s urine. Pregnancy tests give a reliable result only 7-10 days after fertilization, since the hormone in the body appears in sufficient quantities to determine it immediately.
there are two strips on the test:
- The first bar shows whether the test itself is suitable, whether it is defective or expired.
- The second bar shows whether a woman has the hormone hCG in her body.
The scheme is simple: one strip – there is no pregnancy, two strips-there is a pregnancy, not a single strip-the test is unsuitable. Also, the second strip may be slightly noticeable. In this case, you need to take the test again in 2-3 days.
Are mistakes allowed in the pregnancy test?
Yes, the test does not give a 100% guarantee for the diagnosis of pregnancy, even if all instructions are followed. Consider the factors that can distort testing:
- Low concentration of HCG. If you take the test too early (1-3 days after fertilization), the amount of the hormone may not be enough to determine pregnancy.
- Violation of the instructions. It is necessary to strictly maintain the time (4-5 minutes), collect urine in the morning, do not drink a lot of liquid the day before, observe sterility. Instructions are available in all tests, read them before using.
- The presence of other sources of hCG in the body. This hormone is released in the vast majority of cases during pregnancy, but its presence may also be associated with undergoing treatment for infertility, taking certain medications, ectopic pregnancy or oncological diseases (cancer) of the genitals. In the latter case, a pregnancy test can be positive even in men (for example, with testicular cancer, but this is not the only possible cause).