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All about the best pregnancy tests, types and sensitivity

pregnancy test types sensitivity

Pregnancy tests: what are they and how do they work?

Searching for pregnancy is a process that can be more or less long, and different for each couple. But if there is a common gesture to anyone who is looking to conceive, it is to take a pregnancy test. 

That wait, those nerves, those desire to see a positive. And also the disappointment when this positive does not quite arrive. 

But "who" is responsible for these positive or negative results? 

Yes. The pregnancy tests. 

And the reality is that taking a pregnancy test can be quite stressful. And it can be even more so if you are not sure how it works, what method to use and, above all, if you do not know the reliability of the results. 

We are going to see exactly how pregnancy tests work, and how and when to use them and also which are the best pregnancy tests and their sensitivity.

At the end of the post you will see the different sensitivities of the tests and when to do the test to know if you are pregnant according to the sensitivity characteristics of the pregnancy tests.

But first ... where do home pregnancy tests come from? 

 

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The history of pregnancy tests

To know where (and when) home pregnancy tests appeared, we have to go back almost 100 years. We have always wanted to find out if there is a pregnancy, the good thing is that now we can find out very easily. Pregnancy tests have evolved a lot, of course, especially increasing the sensitivity and reliability of pregnancy test results, we tell you the details. 

And it is that in 1925 it was discovered that elevated levels of the hormone HCG (human chorionic gonadotropin) were, in some way, related to pregnancy. 

And yes, it is precisely this hormone that is measured in pregnancy tests to determine whether they are positive or not. But let's not advance events. 

In fact, despite having discovered this implication of HCG in pregnancy, it was not until the 70s that pregnancy tests began to be marketed through outpatient measurement of this hormone. 

The first tests consisted of a complicated system with test tubes and the results took hours to arrive. In addition, these first pregnancy tests gave a high number of false negatives.

Starting in the 80s, pregnancy tests were developed somewhat more similar to those we know today.

The first pregnancy test - similar to the current one - that was marketed was the urine test strip with which, in just 10 minutes and with a little urine on the strip, clear information could be obtained. Of course, the tests were still not very sensitive, so it used to be necessary to wait up to two weeks after the first fault to confirm the positive with guarantees. 

Research to date has been aimed at improving the sensitivity of tests to this HGC hormone. Thus, today, we find tests that offer reliable results from the first day of delay. 

The evolution of pregnancy tests have led, especially in the last decade, to get some digital tests, very easy to use, which are even capable of detecting the weeks of pregnancy in which we are. And also, at a fairly affordable price for most pockets. 

⏰When should the test be performed?

The current reliability of pregnancy tests is high, although rushing is often poor counselor - as in so many other things in life.  

In fact, taking the pregnancy test too soon could give us a wrong result. 

Currently, the vast majority of pregnancy tests claim to be accurate. from the first day of the absence of a period, or even before. However, more accurate results are usually achieved if you wait until after the first day your period is due (or what is known as the first day of your missed period).

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Why wait to do a pregnancy test? 

Waiting for a pregnancy test has to do with the egg implantation process. 

After sexual intercourse, if a sperm has managed to reach the egg and there has been fertilization, the fertilized egg attaches to the uterine lining and implantation occurs. 

This usually occurs about 15 days after fertilization, and the formation of the placenta also begins, in addition to the production of the hormone human chorionic gonadotropin (HCG). 

It is precisely this hormone that is detected by pregnancy tests, but it is necessary for the hormone to enter the bloodstream, and hence pass into the urine, where we can detect it thanks to current pregnancy tests. 

As soon as implantation is consolidated, the concentration of the HCG hormone increases rapidly, doubling every two to three days. For this reason, the later the pregnancy test is done, the easier it will be to detect the positive. And vice versa, the earlier the pregnancy test is done, the more difficult it will be for the test to detect the HCG because there will be a lower concentration of it.  

La most pregnancy tests detect the hormone from a concentration of 20 mIU/ml (milliInternational Units per milliliter of urine). Others pregnancy test detect 10mlu/ml and the most sensitive 5mIU/ml that this is before the first fault. 

In addition, and to understand the variability in the results of pregnancy tests, it must be taken into account that the time of ovulation can vary from month to month and the fertilized egg can implant in the uterus at different times. This moment directly influences the production of HCG and determines the moment in which it can be detected (that is, the moment in which a pregnancy test will give a reliable result). 

If your cycles are also irregular, it's easy to miscalculate your ovulation date, so testing too early can lead to a false negative, as well as a good upset.  

When to do the pregnancy test to get a reliable result?

Although there are ultrasensitive tests that seem to detect the HCG hormone from the first week after conception, the most reliable thing is to carry out a pregnancy test with at least one day of delay of the rule. However, if you perform an ultrasensitive pregnancy test, you can do it even before your period is missed. We tell you all about this in this post. PREGNANCY TEST BEFORE MISSING MONTHLY

That said, and if nerves allow it, the ideal would be to perform the test one week after the scheduled date for the next staining. 

At what time of the day should a pregnancy test be performed?

Although the pregnancy test can be performed at any time of the day, it is recommended to use the first urine of the daya, which has a higher concentration of the hormone HCG, so it is best to do the test just after waking up with the first urine of the morning if you have not peed in the previous 3 hours.

If for any reason, the test cannot be performed first thing in the morning, it is recommended not to drink too much water, in this way the urine will be concentrated and the pregnancy hormone to detect in the pregnancy test, also having more options to see the real test result and not have a false negative when there really is pregnancy. 

What test to choose according to the time of taking the test?

Depending on the time when the test is intended to be performed, attention should be paid to the maximum sensitivity level of the pregnancy test. 

In a normal pregnancy, the pregnancy hormone or HCG can be detected in urine and blood only 7 days after conception. HCG levels continue to increase, exceeding 100 mlU / ml after the first failure and doubling their levels approximately every two days until reaching a range of 11500-300000 mlU / ml in weeks 10-12 of gestation, at the end of the first trimester.

7-10 days after conception there is a concentration of 10 mlU / ml or higher of HCG. This would be equivalent, in regular cycles, to 4-5 days before the lack of menstruation.

From 10 to 14 days after conception there is a concentration of 25 mIU/ml or higher. This would roughly equate to the date your period should arrive. Most pregnancy tests have this standard sensitivity.

📌Types of pregnancy test according to sensitivity to HGC

Pregnancy tests are super easy to use. The choice will be more on your sensitivity to get out of doubt and this is where it can be complicated to buy a pregnancy test and easy to choose wrong. According to their sensitivity, pregnancy tests could be classified into:

From the first day of the lack of menstruation, always assuming that these are regular cycles, all pregnancy tests have sufficient sensitivity to detect the presence of the pregnancy hormone.

Here I leave you the 2 tests that today are the best sellers and with greater reliability, something that I warn you that is also noticeable in the price:

  claer blue pregnancy test Ultrasensitive pregnancy test for before having the lack

Clear Blue digital weeks  Digital pregnancy test and what tells you how many weeks you are

Remember, if you want to know if you are pregnant, you can buy a pregnancy test online or at your pharmacy and find out in less than 5 minutes, you just have to take into account the sensitivity of the pregnancy test and the time of day depending on the moment of the cycle or lack in which you find yourself.

 

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