When a pregnancy is suspected, the most used method to confirm or rule it out is the pregnancy test that you buy at the pharmacy and you can do at home. Thanks to it, you can quickly and easily know if you are expecting a baby or not.
There are many doubts that arise around the pregnancy test, so we answer here the seven most frequent questions about the pregnancy test .
1) How does the pregnancy test work?
The home pregnancy test has a very simple operation. They come in different forms, but they all have a reactive absorbent strip inside that detects the presence of the hormone chorionic gonadotropin (hCG) in urine , the pregnancy hormone.
At the beginning of pregnancy, the cells that will form the placenta begin to secrete this hormone in women, which can be detected through blood or urine , which are the ones we will talk about here.
When the test strip comes into contact with urine, it is able to recognize, with greater or lesser sensitivity, the amount of pregnancy hormone contained in your urine.
2) What pregnancy test to buy?
There are several brands on the market. The best sellers are those that have an elongated shape, similar to that of a pen. They all have in common that they incorporate a display to read the result and an absorbent test strip at one end. Also only the test strips that must be immersed in a bottle with urine are sold, but the first ones are more practical.
There are those that indicate the result in the form of lines, the best known, or the digital ones that represent the result with faces (happy for positive and sad for negative) with an estimate of the weeks of pregnancy.
You should also know that the sensitivity of the test is important, that is, the amount of hormone capable of detecting. There are some with greater sensitivity than others, depending on the brand. Try to buy one that detects the lowest concentration of hCG . For example, a test that claims to detect hCG at 20 mIU / ml (International milliUnits per milliliter of urine) will be more sensitive than one that claims to detect it at 50 mIU / ml.
There are even advanced ones that detect hCG concentrations equal to or greater than 12.5 mIU / ml and promise to give a reliable result even four days before the first fault.
3) When to take the pregnancy test?
As I mentioned before, it depends on the sensitivity of the test. For greater security, it should be done from the first day of absence of menstruation .
But of course, it is not the same in women with regular cycles, who know the day their period should come, than in irregular women who have less control over their cycle.
If you are not regular, it is recommended to do it or repeat it a week after the scheduled date for the arrival of your period .
4) How to do the pregnancy test?
It can be done at any time of the day, although for greater safety it is recommended to do it with the first urine in the morning , which is the one with the highest concentration. First of all, you should open the package and read the instructions.
You must remove the packaging, uncover the test and soak the test strip with your urine for 5 seconds. There are two ways to do this: urinate directly on the strip, or do it in a bottle and immerse the strip in the urine for 5 seconds.
Once done, you should replace the lid and let it rest on a flat surface for 3-5 minutes (according to the instructions). Then you can proceed to read the result.
5) How to read the result?
Most of the tests give two results: a line that indicates if there is pregnancy or not and another of control, that indicates if the test has been done well or not.
If two lines appear, even if the intensity is low, the result is positive , on the other hand, if only one line appears in the control window, it indicates that the test has been carried out correctly but the result is negative .
In the digital ones there are no lines, but the result appears in the form of a happy face when there is a pregnancy and a sad face when there is no pregnancy.
6) Can the pregnancy test fail?
Home pregnancy tests have a reliability of between 75 and 97 percent if the result is negative, while if the result is positive the reliability is 99 percent.
Can the test give a false positive? In women with hormonal disorders or with certain diseases that cause the secretion of the human gonadotropin hormone, such as trophoblastic diseases or some cancers, the result can be positive without pregnancy.
Can the test give a false negative? If done too early, the levels of the pregnancy hormone can be very low and not yet detected in the test.
7) In which cases should the pregnancy test be repeated?
If the result has been negative but menstruation still does not occur, you must repeat the test 2 to 4 days later , when the presence of the pregnancy hormone should already be detected.
You should also repeat it if no result appears in the control window, you may have done it wrong. Read the instructions again and repeat the test.
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In Babies and more | Ask the midwife: What is a pregnancy test? Can a pregnancy test fail?
