Can there be a pregnancy test error: percentage, probability, statistics, reviews

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You’ve stopped hearing the morning alarm clock, you’re panicked in traffic jams, and the smell of your mother’s recently adored cutlets makes your eyes cloudy and makes you want to run away. Either you are tired and need rest, or... pregnant. A test will definitely help you find out.

All modern pregnancy tests are based on one principle: they are impregnated or coated with a reagent that reacts to the presence of the hormone gonadotropin (hCG). It begins to be produced from the first days of pregnancy, and its amount is constantly increasing. But for the reagent it is not immediately noticeable. The higher the sensitivity of the test, the faster it will be able to detect hCG: if you see a reading of 10 mIU/ml on the package, it means that you have a specimen that recognizes gonadotropin in a lower concentration - on the 7-10th day from the moment of conception. A strip with a sensitivity of 20 mIU/ml will be able to find out whether you are pregnant or not only from the first day of your missed period. Gonadotropin is excreted in the urine, so it will become experimental material for home research: you will need to put the test in it and wait a little. Two lines that appear mean that you are pregnant, one line means a negative result. But keep in mind that most tests require you to pee in a jar as soon as you wake up, when neither coffee nor yogurt has changed the indicators and the maximum amount of hCG in the body.

Strip, jet, tablet

The most common, inexpensive and because of this very popular pregnancy test is the strip strip. It's basically an oblong piece of cardboard, similar to the litmus test your chemistry teacher would hand you during labs. The strip has average sensitivity and costs from 30 to 100 rubles.

The next generation of pregnancy detectors is a tablet test. It can be called the “tuned older brother” of the strip strip. The price of a tablet ranges from 100 to 400 rubles, but its sensitivity is the same as an ordinary one. It's just more modern and convenient. The test itself is placed in a plastic case and does not need to be immersed in liquid: it comes with a charming pipette, and there are two windows on the front side. Just drop a drop of urine into the first and you will get the result in the second. This option is relevant if you want to keep the memory test: it looks aesthetically pleasing, and you can show it to your grandchildren.

If complex manipulations with glasses are not for you, choose the jet test. It costs much more than the first two - 200-600 rubles, but to see the same one or two lines appearing, you just need to pee on the device itself and get an immediate result. Moreover, due to the high sensitivity of the test, this can be done not in the morning, but at any time of the day. The inkjet pregnancy detector contains particles that, when the desired hormone is detected, instantly attach to it, thereby making it visible. Of course, this option is indispensable when you want to know the answer immediately, but don’t have a glass at hand.

The second strip may be pale (the result depends on the hCG level), but it should be clear! Only in this case does its appearance mean pregnancy. If there is a blurry spot instead of a recognizable line, the test is invalid.

Pregnancy test before delay

It is absolutely known that the mentioned hormone begins to be produced in a woman almost immediately after conception, however, its concentration is initially low. In a non-pregnant woman, human chorionic gonadotropin may be present in the body in small quantities - up to 15 IU/l. In a pregnant woman, it is produced in much larger volumes. In the first week - an average of 150 IU/l, in the second and third - 2000 IU/l.

Therefore, it becomes clear that there is a high probability that before the delay, the test will show pregnancy, if any. The study can be carried out at the end of the first week after conception. However, it is worth remembering that the earlier the test is carried out, the greater the likelihood of error. Sometimes two stripes appear on the dough sheet, but one of them is slightly pronounced. In this case, it is impossible to broadcast with confidence that the test is positive. This picture can be observed in several cases. For example, the concentration of the hCG hormone is still low. Therefore, it is advisable to repeat the test after one or two days.

Test for Trinity and Neo

If, in the continuation of the fantasy trilogy "The Matrix", Trinity wanted to find out whether she was expecting a child with Neo or not, she would probably have used an electronic test. Compared to paper strips, it looks impressive, and it costs accordingly - from 350 to 1500 rubles. But in reality it differs from all its predecessors only in the presence of a display on one end of the litmus test. By performing the same manipulations as with the test strips, you will launch the same mechanism for searching for hCG in the urine. Only now the result will be read by a small electronic mind and displayed on the screen, on which it will be written: “you are pregnant” or “you are not pregnant.” Electronic tests, like any other, are disposable, so after enjoying a modern miracle, you throw it in the trash. Therefore, you should think twice before shelling out money for “future technologies.”

If doubt is your middle name, buy several tests at once. By trying again to determine pregnancy the next day, you can check whether the previous copy “lied” to you.

How tests determine the presence or absence of pregnancy

Many women want to see the two coveted lines on a pregnancy test, so almost the next day after unprotected intimacy they begin to conduct a home test. But what period is considered optimal for such studies? To answer this question, we need to delve deeper into how tests work.

Immediately after conception and the attachment of the egg to the uterus, the pregnancy hormone hCG (human chorionic gonadotropin) begins to be intensively produced.

The hCG hormone is constantly present in a woman’s body, but in the normal state its concentration is not enough to confirm the state of gestation and the appearance of the second strip on the “assistant” of the expectant mother or, if we are talking about an electronic gadget, then the “+” sign.

Whatever fashionable and modern pregnancy tests exist, they all operate on the same principle: responding to an increase in hCG. Inside all tests there is a test strip colored with a special reagent that reacts to changes in the chemical composition of urine that are observed after the birth of a new life in the womb.

The presence of two lines on the test is a sign of pregnancy

Experts recommend conducting the study a few days after the day when menstrual flow should have started. But ultra-sensitive tests can inform about the onset of conception two to three days before menstruation.

HCG is found both in the urine and blood of a pregnant woman. Therefore, to confirm a positive test result in a medical facility, specialists examine blood from a vein. It is possible to determine conception in a laboratory several days earlier than with a test.

False alarm

Surely you have heard stories more than once: “I took two tests, both showed that I was not pregnant, and after three months someone moved in my stomach.” Indeed, the stripes can be wrong. The accuracy of the result depends both on the integrity of the manufacturer (quality of the reagent and technology) and on the storage conditions of the test. Therefore, experts advise using well-known brands with a proven reputation. But they can also show incorrect results. For example, if you drink too much liquid the day before, it will dilute your urine and reduce the concentration of the pregnancy hormone in it. You also risk getting a false negative result if your hCG levels are still very low. However, sometimes tests show two stripes in the absence of pregnancy. After all, gonadotropin is also released in the blood during certain diseases: ovarian dysfunction and various tumors. And, of course, you should not hope for a true result if you are taking hormonal drugs or diuretics.

When choosing a pregnancy test, look at the expiration date of the strip. It is important that it expires no earlier than in a month.

Interesting statistics on the banding of tests and hCG on DPO and DZ with further CONFIRMED B.

STATISTICS of banding tests and hCG according to DPO and DZ with CONFIRMED later B. Preface. The statistics were created to show at which DPO the earliest WHAT test was shown by B (it is clear that these were the most sensitive tests, from 10 units + Blue, View). The number of stars (*) next to the nickname means which day the test is being done, for example * - the first day, ** - the second day, etc. The name of the test is not indicated everywhere, because it was not always indicated by the lucky owner of the striped test. Statistics also show that the rate of hCG synthesis, depending on DPO, is indeed very individual. I remind those who are especially impatient that the test will most likely show B starting at 12DPO, at least at 10DPO, since implantation is usually completed around 12DPO. Early test results are very rare, they are the exception, not the rule, so try to wait patiently for at least 12DPO, and ideally 1DPO. From our practice, situations are very common when the test showed a ghost before the delay, but everything ended with M - the fact is that only 50% of fertilized UCs are able to successfully implant and develop. If implantation is unsuccessful, BD (biochemical B) may occur - UC will be rejected during M. So, in order to avoid unnecessary frustration, it is better to wait for 1DZ. Here I also attach data from Fertility about the same test streak statistics: https://www.fertilityfriend.com/Faqs/When_can_I_expect_a_positive_HPT_if_I_am_pregnant.html Implantation statistics:

(taken from here https://www.eva.ru/forum/show?idPost=16472595) 3-5 dpo - 0.68% 6 dpo - 1.39% 7 dpo - 5.56% 8 dpo - 18.06% 9 dpo - 36.81% 10 dpo - 27.78% 11 dpo - 6.94% 12 dpo - 2.78% To the same data:
ARTICLE “PHYSIOLOGY OF IMPLANTATION” (CIR)
https://www.cironline.ru/articles/pregnancy/book1/125/ These data once again show that only by 12DPO implantation is usually completed, and the developing PU begins to synthesize hCG and enter the mother’s body, which is what the determination of B by a test or blood test for hCG is based on.
It is believed that hCG appears in the blood earlier than in the urine. On Fertility, in the gallery of graphs and tests for B, there is data that only by 17-18DPO tests began to show B, until 16DPO they were negative. Occasionally there is evidence that they found out about B even later - the latest information I know is 24DPO. at 20dpo the blood test for hCG was still negative. This is also worth considering when doing a test or donating blood. And now the statistics themselves: Our statistics on DPO and DZ: 4DPO
1. Masyapa* - 2-3 tests - |
(tests were Frau, I-test, Evi). 5DPO
1. lyubasha - hCG = 0 2. Masyapa** - 2-3 tests - |
(tests were Frau, I-test, Evi). 6DPO
1. Masyapa*** - 2-3 tests - |
(tests were Frau, Blue, I-test, Evi). 7DPO
1. lyubasha* - in the morning hCG = 0, evening Blue electric.
weak.2nd weak. (the test should have written “Pregnancy”, but it didn’t, but when you look at it, it was weak. 2nd weak.) - ***THE EARLIEST B-TEST RESULT OF OUR STATISTICS*** 2. Masyapa**** - 2-3 tests - | (tests were Frau, Blue, I-test, Evi). 8DPO
1. lyubasha** - Blue electric.
weak.2nd weak. (the test should have written “Pregnancy”, but it didn’t, but when you look at it, it was weak. 2nd weak.) 2. Masyapa***** - Evie - the shadow of a ghost, appeared 10 minutes later. 9DPO
1. Buble* - Blue, View of ghosts 2. lyubasha*** - Blue morning is weak + 3. Masyapa****** - Frau - the shadow of a ghost, appeared 10 minutes later.
10DPO
1. Shaggy* - Vue ghost 2. Mill* - 6 tests (Frau, Evi, I-test) 2nd weak, in the evening Blue + 3. italove* - BB, I-test 2nd weak, Blue weak + 4. Buble** - simpleHCG ||
5. lyubasha**** - Blue morning weak + 6. Masyapa******* - 2 times Blue (day, evening) - weak + (a thin light blue line appeared after 2 minutes). 7. LSt* - evening cassette Frau ghost, appeared after 10 minutes. 11DPO
1. cayenne* - ghost 2. Shaggy** - View 2nd weak.
3. lyubasha - hCG 39 - ***EARLIEST B-result of hCG of our statistics*** 4. Red Katenok* - Blue + 5. Masyapa******** - Frau (morning) - very weak, but the plump 2nd strip, hCG = 34 - ***THE EARLIEST B-result of hCG of our statistics*** 6. LSt** - morning cassette Frau 2nd is weak, Evitest 2nd is weak. morning, afternoon, evening, appeared after 10 minutes. 12DPO
1. Talesya* - Canada ghost 2. cayenne** - Eva 2nd weak.
3. Niki* - Blue + 4. Shaggy*** - (evening) Frau 2nd weak. 5. tigriza* - beShure 2nd weak. 6. Gordeniya* - (evening) Frau (?) ghost 7. I'm pregnant (Yulek+)* - (day) Blue +, hCG 78.9 8. Masyapa******** - Blue + (much more noticeable than at 10DPO). 9. cookies* - (morning) Frau 2nd weak, (evening) Blue clear + 10. LSt*** - morning Evitest regular and cassette, evening Frau 2nd weak. 13DPO
1. Lyalik* - (day X) ghost 2. Lysenchik* - Frau 2nd weak.
(before this there were ghosts) 3. Mill - hCG = 173.6 4. italove - hCG = 96.5 5. tigriza** - View, Itest, and some other 2nd weak. 6. lyubasha***** — sense test from 25 units. 2nd weak, hCG = 144 7. Gordeniya** - (morning) Frau (?) - 2nd weak. 8. cookies** - (day) Blue +, hCG = 37.6 9. LSt**** - morning, evening Evitest || 14DPO
1. Lubov28* - Blue + 2. Rafaella* - ||
3. Shaggy - hCG 783 4. Lyusenchik - hCG 200 5. Gordeniya*** - (evening) Frau (?) || 6. cookies*** - (day) bishur 2nd weak. 7. LSt***** - morning Evitest || 15DPO
1. chertenok13* - BB ||, Be sure 2nd is weak.
2. Talesya** - (1DZ) Mon Ami 2nd weak. 3. Panti - hCG 28.5 4. Niki - hCG 429.6 5. lyubasha****** - sensitivity test from 25 units. 2nd weak. 6. geisha* - Evitest ghost 7. cookies**** - (day) I-test 2nd weak. 8. LSt****** - morning, evening Evitest || 16DPO
1. Mill - hCG 895.8 2. Gordeniya**** - (morning) Frau (?) ||
3. Talesya*** - (2DZ) Mon Ami 2nd faint.brighter than yesterday. 4. I’m pregnant (Yulek+) - (3DZ) hCG 746.8 5. geisha** - 2nd weak. brighter than yesterday 6. LSt******* - morning Evitest, afternoon evening Frau || 7. Masyapa********** - Evitest ||, the 2nd bright one appeared immediately. 17DPO
1. Rafaella - hCG 590 2. italove - hCG 542.1 3. Talesya**** - (3DZ) (day) I-test ||, hCG = 734 4. geisha - (5DZ) - hCG 69.9 5. LS******** - morning, evening Frau ||, hCG = 559.4
18DPO
1. Gordeniya***** - (evening) Frau (?) ||
2. cookies - hCG = 415 3. LS********* - morning Frau || and so on until 30DPO, +1 I-test. Day X
1. setamm* — ||
2. Lyalik* - ghost 1DZ
1. setamm** - ||
2. cookies* - only 3 tests, one has a ghost, the rest (apparently Blue) + + 3. Talesya** - Mon Ami 2nd is weak. 2DZ
1. setamm*** — ||
2. Talesya*** - Mon Ami 2nd weak. (brighter than on 1DZ) 6DZ
1. Kapuzik* - ||
2DZ
1. Gamma* - Frau 2nd weak (tests did not show this before)
7DZ
1. Gamma - hCG 214

Expert opinion

Mikhail Alyokhin pharmacist:

– Don’t forget that two lines on the test are just a reason to contact a gynecologist for an examination. After all, only in a clinical setting is it possible to reliably determine the presence of pregnancy and its correct development. Although a new generation of tests have already appeared in Europe, the results of which leave no doubt. These devices not only detect the presence of hCG in the urine, but also find an atom in the molecule of this hormone that appears specifically during pregnancy. But the Russian market does not yet even dream of the appearance of such tests in pharmacies. They are too expensive and are unlikely to be in demand among customers.

Using the test

There are several types of home tests to detect pregnancy. Most of them operate on the same principle. The only difference is the diagnostic method and the way the result is displayed.

So, there are jet tests that just need to be placed under a stream of urine. There are tests in the form of a cassette on which you need to drop a few drops of urine from a special pipette. As a rule, such cassettes have high sensitivity. The most common and cheapest are strip tests. They need to be lowered to a special mark in a small container with urine and held for 15-30 seconds.

Most often, the presence of pregnancy can be judged by the appearance of a second stripe. However, its brightness does not matter. The first strip is a control line and indicates that the test is not spoiled. Sometimes, instead of two bars, you can see a plus sign. This result also indicates the presence of pregnancy (accordingly, a minus indicates its absence).

Recently, digital tests have become increasingly popular. The diagnostic result obtained using this test is very easy to interpret. The electronic display will display not only a message that you will soon become a mother, but also the expected period from the date of conception.

Reason to buy a test

Your mammary glands began to hurt and swell.
Instead of menstruation, pink spotting appeared.
You feel a nagging pain in your lower abdomen.
You feel sick or vomit in the morning and throughout the day.
You begin to get tired quickly and fall asleep as soon as you find yourself in the chair.
The desire to go to the toilet in a small way began to arise more often than usual.
You began to experience migraines that were unusual for you.
You have a pigment stripe from your pubis to your navel or the skin around your nipples has darkened.
You suddenly started eating foods that you previously couldn’t stand.
You became nervous and whiny. And in general, your mood ceased to belong to you.

Great-grandmother's methods

Israel - barefoot on the grass. The ancient Israelites forced their young wives to walk on soft grass: if the tracks were deep and the grass was wrinkled, it meant she was pregnant. By the way, this is a very adequate test, because the expectant mother’s center of gravity shifts, and her gait becomes heavier accordingly.

Egypt - a thread around the neck. In the era of the Egyptian pharaohs, a very thin silk thread was tied around the neck of a married girl. If she was torn, this was regarded by her relatives as confirmation of pregnancy. And this happened because in an interesting position the thyroid gland enlarges slightly.

Greece - dust in the eyes . The ancient Greeks had the strangest pregnancy tests. Despite the fact that it was the most advanced power in matters of medicine, with Hippocrates at its head, they... broke some mysterious red stone in front of the girl’s face. If dust from it got into the young lady’s eyes, the Hellenes concluded: she was pregnant.

Online test

If a woman does not have an urgent need to immediately find out whether she is pregnant, it is better to wait until her period (or from a delay). Then confidence in the accuracy of the result will be much higher. While waiting for this time, women can use online services to help determine whether she is pregnant or not.

Of course, any pre-term pregnancy test purchased at a pharmacy will be more accurate than an online questionnaire. On the other hand, it is absolutely free and does not require much time. Women who have used online testing say that the result in most cases reflects the real picture. These reviews show that using an online pregnancy test is not without merit. What is emphasized when creating such a questionnaire:

Features of a woman's body.
Changes in the functioning of the body that she noticed after ovulation.
State of health and analysis of possible signs of pregnancy.

The use of online tests has become very popular among women who would like to find out whether they are pregnant or not, a few days before the expected start of their period.

There is hardly a woman in the world who would not want to find out about her pregnancy as early as possible. The first physiological signs of a delicate situation, such as morning sickness, frequent urination, enlargement and tenderness of the mammary glands, are quite subjective and appear after a delay in menstruation.

An ultrasound examination of the uterine cavity will also show a pregnancy of at least five weeks. That is why scientists have set themselves the task of developing a pregnancy test before a missed period. And modern technologies have allowed them to successfully solve this issue.

A pre-term pregnancy test for home use is based on a qualitative determination of the level of human chorionic gonadotropin (hCG) in a woman’s urine. HCG is a special hormone that begins to be produced by the embryo immediately after it implants into the wall of the uterus.

Below are the norms for hCG levels in blood serum (in mIU/ml) in women:

no pregnancy (0−5)
pregnancy in question (5 -25)
1−2 weeks (25−156)
2−3 weeks (101-4870)
3−4 weeks (1110-31500)
4−5 weeks (2560-82300)
5−6 weeks (23100-151000)
6−7 weeks (27300-233000)
7−11 weeks (20900-291000)
11−16 weeks (6140-103000)
16−21 weeks (4720-80100)
21−39 weeks (2700-78100)

It should be clarified that these standards are approximate and depend on the specific laboratory in which the analysis is performed. In addition, the concentration of hCG in urine is usually slightly lower than in the blood.

Most home tests can “catch” hCG, the content of which in the urine exceeds 25 mIU/ml. Although more highly sensitive tests with a threshold of 20 mIU/ml and even 10 mIU/ml are also sold.