How does the pregnancy test work? Test strip: the principle of operation

Before almost every woman at a certain time, the question arises whether she is pregnant. Now, to find out whether the woman is in an "interesting position", there are special tests. What kinds are they? How does the pregnancy test work? You will find out the answers to these questions by reading the article.

Principle of operation

What is the principle of the pregnancy test? By the principle of the presence in the urine of the hormone hCG, which appears as soon as the fertilized egg is fixed in the uterus and begins to develop. If a week has passed from the moment of conception, then this time will be enough to determine if a woman has become pregnant by the analysis of urine.

Test work

The surface of the dough is treated with a special reagent. If there was fertilization, a special reaction begins between the specific composition and the hormone hCG. It is reflected in the diagnostic zone in the form of a strip, the color of which can be of varying degrees of intensity.

Accordingly, if the hormone in the body is absent, that is, the woman is not pregnant, no reaction will follow and the test will remain unchanged. The so-called control zone is still present in the test. It is in it appears an additional line with a positive result. Let's sum up what was said, if the woman is "in position", the test will reflect two strips.

Types of pregnancy tests

Tests for determining pregnancy are as follows:

• Test strips;
• Tablet,
• Inkjet;
• Test systems with tanks.

Test strips

How to use this pregnancy test ? This is the very first generation. They are most easy to use. Therefore, their cost is low. Very popular with girls, rank first in terms of sales. Such tests a huge selection is presented in almost every pharmacy.

How does the pregnancy test strip work? The principle is simple. Tests are reagent-impregnated paper or fabric strips. They need to be lowered for a few seconds in the urine collected especially for this, preferably the morning (because of the highest content of hormones in it). Leave it for up to ten seconds and then watch the result. At the same time, the strip is not fully submerged, but only a specially allocated part for this purpose.

At what time does the pregnancy test work? On the first day, menstruation delays are guaranteed up to ninety percent of the truthfulness of the information. With the passage of time, the reliability of the result becomes higher. And in a week's time the data will be 100% accurate.

Among the minuses of such tests can be noted quite low sensitivity. It is also not very convenient that an additional capacity for urine is needed for rapid analysis. Strips often show an inaccurate result due to the fact that the reagent is applied to paper that does not withstand concentration. In addition, when using it, mistakes are often made, which also leads to unreliable results.

Tablet Tests

And how does a pregnancy test of this type work? This species is more sensitive. Such tests determine the "interesting" position much earlier. They also examine urine. For this purpose, a drop of urine is applied to the test window with a pipette. She, spreading through the embedded tissue, reacts with the reagent soaked in it, the result appears. Such tests are much more expensive in cost, but also more true. They are even used in medical institutions.

The advantage of this variety is the presence of a pipette. However, such a test also requires preliminary collection of material for analysis into a separate, clean container.

Inkjet Testing

Inkjet tests are the most advanced method for detecting hCG. It is enough to know how the pregnancy test works to recognize its undeniable superiority. This is a more complex device with a high level of sensitivity. In the jet test, the concentration of the reagent that reveals the hCG hormone is higher. The result can be seen after one minute, and it is very reliable. That's just the cost of these tests is incommensurably high, when compared with strips and tablets.

However, high cost can be forgiven for the convenience of use. No need to look for a jar, just put the tip of the dough under a stream of urine. And you can do this at any time of the day because of the very high sensitivity of the test, and not just in the morning.

The rod of these tests consists of fibers impregnated with a special reagent. Its high concentration makes it possible to isolate the hormone of pregnancy even with the smallest content of it in the urine.

Test systems with tanks

From the title it is already clear that the kit includes a tank, in which the test is built. All this makes the procedure extremely clear and simple. The urine is collected in the reservoir, and the result is subsequently displayed on the test.

Electronic Tests

Until now, how the electronic pregnancy test works , is of great interest. The test strips, which belong to the first generation, are easy to use and affordable. But it is their electronic counterpart that can create a real miracle. After all, he will not only determine the existence of ancestral life, but also name the approximate duration of pregnancy.

In this case, the test is very unambiguous. It shows only plus or minus. When pregnancy is present, her period is additionally reported.

Test Selection

In order not to make a mistake with a choice, it is necessary to know, how many and how a pregnancy test of one kind or another works. Regardless of whether the child is coveted or not, every woman wants to be convinced as soon as possible of a positive or negative result in order to dispel the doubts that torment her. Of course, you can buy cheaper tests, but the result is not guaranteed to be reliable.

How to choose a good test? It is necessary that its sensitivity be high. It would be nice to choose a test from a well-known manufacturer. This in some way can be saved from fakes. It is known: the lower the price, the worse the quality.

Using the test at home

How to use a pregnancy test? Before starting the procedure, it is necessary to read the attached instruction as carefully as possible in order to avoid various problems in the future. The test procedure is largely the same for all types of tests. But there are important trivia, if you ignore them, then the reliability of the result may be in question.

First, the urine is collected. It is best to determine the pregnancy in the morning. Since it is at this time of day, the concentration of the hormone reaches its highest value. The latest developments in rapid tests are considered to be hypersensitive, so they can detect HCG at any time of the day. But nevertheless it is not necessary to drink a lot of liquid specially to quickly go to the toilet and learn the result.

When can I use it?

When does the pregnancy test begin? Depending on the degree of sensitivity of the test, the result may be a week after the delay, on the first day of the delay. Electronic tests are ready to diagnose the result long before the expected menstruation. Thus, through how much the pregnancy test works, depends on the individual characteristics of the female body, on the cost and quality of the diagnostic tool.

Errors in use

Waiting for the result is necessary during the time specified in the instruction. Typically, this is a few minutes, after which the reagent dries. A second weak streak may appear, but it will not mean pregnancy. Do not use tests after the expiry date.

A small conclusion

Now you know how the pregnancy test works. The information in the article will allow you to choose the right option and use it yourself.