A positive pregnancy test is always a big deal. For some it is joyful and long-awaited, for others it is unexpected and not the most pleasant. But in no case can a 2-strip test leave a woman indifferent. A positive result of home pregnancy diagnostics has its own nuances and subtleties, which this article will tell you about.
When does the 2nd line appear?
If you hold in your hand a test with two strips or a "+" sign, it means that the result of the home self-test is positive. The second line appears for a reason. She suggests that a woman's urine contains a high content of a specific substance - chorionic gonadotropin (hCG). And whatever the test you bought (with a regular strip or an expensive digital device), the principle of operation is stable: there is hCG - there is a strip, there is no hCG or very little of it - there is no strip.
The part of the test system that comes into contact with urine has a double working area. The first line is for any result. She, in fact, says that the device is in perfect order and can be used. But in the second part, the test, a chemical reagent is applied with a sensitivity to the hCG hormone molecules.
As soon as the content of this substance in urine exceeds the sensitivity threshold of the system, the reagent will immediately report this fact by staining in blue, blue or pink color (depending on the type of reagent and the specific brand of the test system).
If your test is positive, it means that the conception was successful and you are pregnant.
HCG does not begin to be produced immediately after fertilization. The embryo, after the fusion of the parental gametes, moves along the oviduct into the uterus for about three days. Then from days to three days can freely "float" in it. Implantation is possible for 6-9 days from the moment of fertilization.
The embryo penetrates into the endometrial layer, literally "burrowing" into it, and the villi of the outer part of the fetal membrane connect with the blood vessels of the mother's body and begin to produce chorionic gonadotropic hormone. This substance is necessary for the embryo to have a chance for further development.
Without it, the corpus luteum, formed during ovulation on the ovary, will die, regress, progesterone will become small, the level of estrogen will rise, and the endometrium will begin to be rejected along with the embryo - a miscarriage will occur. This mechanism is at the heart of every woman's period. And it is precisely because of the high progesterone that the next menstruation will not occur if the woman becomes pregnant.
HCG rises in a woman's blood gradually, subject to certain biological and biochemical laws. So, every 48 hours, the concentration of a substance in a woman's body approximately doubles. The growth of the hormone in urine is slower, in the fluid excreted by the kidneys, the substance appears later, and in smaller quantities. And if the test showed two stripes, this means that the sensitivity threshold has been exceeded.
Tests have different abilities to capture chorionic gonadotropic hormone molecules. Standard (a threshold of 25-30 mIU / ml is indicated on the package) usually determines pregnancy later, after a delay. And ultrasensitive (from 5-10 mIU / ml to 20 mIU / ml) can show a second strip even before the delay of the next menstruation officially begins.
What does it look like?
A positive pregnancy test result usually does not cause significant difficulties in decoding. Depending on the test model, it can be two strips of blue or red color (if the test is a strip strip), "+" in some tablet and inkjet tests, pregnant in the digital model.
Some electronic testing systems can additionally determine the gestational age in weeks.
When using, it is very important to remember that both stripes should be clear. Only two equally colored, clear and bright stripes are a definite positive result, which should not be in doubt. With one strip, the test is called negative, and in a situation where there are no strips at all, it is generally accepted that the test is faulty, it is expired, invalid, you need to purchase another and repeat the diagnosis.
Many women wonder whether a test with a weak two stripes or stripes of varying degrees of staining is considered positive. For example, one is bright and clear, and the other is faint, barely noticeable, indistinct, blurry. Such tests are called questionable or weakly positive.
A questionable reason for obtaining a weak positive result may be too early a period chosen by a woman for self-diagnosiswhen the level of hCG in urine is still insufficient, it is low. It has already approached the threshold of the system's sensitivity, but it is not yet very convincing for the reagent, and therefore the test may well give just such a result. You don't need to do anything special. Wait a day and repeat the test every other day, and then the stripes will definitely become brighter and more convincing.
Unfortunately, sometimes a weak second strip, if the test is done after a delay, can speak about pathologies of early pregnancy, in which the level of hCG is insufficient... In any case, a blood test for the exact quantitative value of hCG will help to clarify the question of the presence of pregnancy, confirm or deny the results of home testing, as well as assess the possible risks. It can be done already from 23-24 days of the cycle, and even before the delay, a woman will be able to get all the answers to her questions.
Timing
The terms on which you can get a "+" are incredibly exciting for women. Especially those who are in a state of active pregnancy planning. To correctly determine the term, Let's first decide from what period we need to count the days. Many people think it can be counted from the day after conception. And it would be ideal if humanity learned to determine the exact day of conception of a person.
While this, alas, is impossible, and when exactly fertilization occurred, no one is able to answer.
The thing is that sperm can live in the genital tract for up to 3-4 days without losing the ability to fertilize, and sexual intercourse for such an amount of time before ovulation, during ovulation and during the day after it can equally be decisive. I.e, the day of intercourse and the day of conception are sometimes very different days.
Therefore, it is customary to consider the period of the second half of the cycle from ovulation. In women, it usually falls on a day, which is easy to calculate by subtracting 14 days from the cycle. Of course, you get a very approximate date, and real ovulation can occur both earlier and later, but the error in any case will be small.
The days in which planners measure the waiting time are abbreviated as DPO (days after ovulation). And if we count in them, we can decide when to start doing home testing.
- 1-3 DPO - the embryo moves through the oviduct, it has not yet reached the uterus. If at this stage something interferes with its progress, an ectopic pregnancy may occur. The level of hCG in the body of pregnant and non-pregnant women, and even in men at this time, is exactly the same - it does not exceed the average minimum normative values (from 0 to 5 IU / ml).
- 4-5 DPO - the embryo is in the uterine cavity. It hasn't attached yet. Under the action of progesterone, produced by the corpus luteum (temporary, recall, the gland), the endometrium layer grows and increases, so that the task of implantation for a new life is facilitated.
- 6-9 DPO - during this period, implantation is possible at any time. It lasts 40 hours, and includes two stages: adhesion (adhesion of the ovum to the inner wall of the uterus) and invasion (immersion in the endometrial layer). At the end of 40 hours from the moment of the beginning of adhesion, the chorionic villi produce the first, as yet insignificant portion of the chorionic gonadotropic hormone.
- 10-13 day DPO - the first rise in the level of hCG. Around this time (24th, 25th, 26th day of the cycle, or just DC), a blood test can be done. Ultrasensitive tests (5-10 units of sensitivity) can be done with 25 DCs, and tests with high sensitivity (15-20 units) with 27 DCs.
- At 14-15 DPO you can use tests with the usual average statistical sensitivity.
Thus, after conception, there is no point in trying to get a positive result for at least 10 days.
It's too early to do tests on day 21 of the cycle., because it is during this period that implantation will presumably take place, and the level of human chorionic gonadotropin will be low, even if the conception was quite successful.
Before menstruation, sensitive test systems may show 2 strips, but it is much more likely to get weakly positive results or even negative ones, especially if ovulation is delayed for several days, and conception and implantation occurred later than expected.
Consider this if in the current cycle were nervous, flew on an airplane, changed time and climatic zones, if no later than 2-3 months ago they stopped taking oral contraceptives, with which they were previously protected. All this can affect the timing of ovulation, and it can be both early and late (late is a more common variant of the violation of the ovulatory phase).
Considering that in different cases the amount of chorionic gonadotropic hormone can be strikingly different from the existing tables, norms and, in general, ideas about the rate of its growth, manufacturers of test systems recommend doing tests no earlier than from the first day of missed periods or 2 days after the delay. By this time, hormone levels are usually elevated in all pregnant women.
Manufacturers do not give any guarantees of accuracy for test results before the delay. It is believed that 5 days before menstruation (on the 23rd day of the cycle with a 28-day cycle), the accuracy does not exceed 50%. But with each subsequent day, it grows, and already 3 days before the expected menstruation (on the 25th day of the cycle) it exceeds 85%, and the day before the start of the delay it approaches 90%.
Summing up all of the above, you should remember that the first home tests can be started at the earliest from 11-12 DPO, and blood for analysis in the laboratory can be donated at 10 DPO.
What can affect accuracy?
The accuracy of home test systems for determining pregnancy in reality is significantly lower than that declared by the manufacturer for advertising purposes. A home test cannot give a urine result with an accuracy of 99%, since only one method has such accuracy. - laboratory blood test for hCG. All other methods are less reliable.
Accuracy naturally declines as the woman gets tested early. The more days remain before the expected day of the onset of the next menstruation, the lower the accuracy of the study.
How accurately you will know the features of your cycle and the time of ovulation, and depends on how accurately you can calculate the time before the start of the diagnosis.
Accuracy can also be affected by errors during the procedure. Often women make common common mistakes: immerse the test too deep in the urine, wait too long for the result, and end up risking a so-called ghost strip... This is a gray second line in the test zone, which forms after drying and does not mean pregnancy at all, as many hope, but just a trace at the site of application of the reagent.
It is these second strips that are often misleading, and women are amazed when, with such a "positive" test, menstruation begins on time. The fact is that there was no pregnancy, it was only considered in the usual used reagent.
The hormonal background of the female body also affects the accuracy of the results. If she took hCG drugs, which usually happens in the treatment of infertility by in vitro fertilization, when ovulation is stimulated by hormones, then the hCG level remains elevated for at least one and a half to two weeks, and the test can deceive, showing two strips, while pregnancy actually no.
If a woman has cancer, then such neoplasms are capable of independently producing hormones, and hCG is no exception. The test may be wrong. The possibility of purchasing a low-quality dough should not be ruled out: no one has canceled production defects, violation of the storage conditions, transportation and sale of such products.
Diagnostic rules
You can improve the accuracy of the result if you follow the simple rules of self-diagnosis. First of all, buy tests only at the pharmacy. If you see test systems at the checkout of a store, refrain from purchasing - there is no guarantee that the storage conditions were maintained correctly.
Another important nuance to pay attention to is the expiration date. It is not customary for women to watch it, unless, of course, butter or dairy products are bought. But in vain, because an expired test is a product in which the chemical properties of the reagent are impaired or partially lost.
That is why the expiration date is always put on the packaging.
Do the test in the morning, on your first urine sample after waking up. It is the densest and most concentrated in composition and components, and therefore it is more likely to detect signs of hCG molecules in it. This is very important for those who start testing before missed periods. After there is a 5-8 day delay, there is no longer a big difference in what urine will be for diagnostics. Usually, the concentration of the hormone by this time is already high, and is easily determined in urine throughout the day. The main thing is not to drink a lot of liquids 4-5 hours before the test.
Read the instructions carefully and follow them carefully. Test systems require different approaches, different residence times in urine. For example, strip strips should not be immersed too deeply in a liquid, and very it is important not to get liquid on the working electronic part of the device. Each model has its own nuances. Up to half of all erroneous tests are the result of disregard for instructions.
Price in no way determines the accuracy and efficiency of a test system. There may be cheap and very accurate tests, or they may be expensive and questionable. Therefore, base your choice on the threshold of sensitivity and women's reviews about a particular brand. Before the delay, it is better to take systems with a sensitivity threshold 5 to 15 units per milliliter. And after her - from 20 units and more.
Separately, I would like to say about some women's forums, where women are advised to wash well before the test, and then insert a tampon into the vagina so that particles of vaginal secretion do not get into the urine. All these measures are unnecessary.
You don’t do a general urine test or a bacterial culture test. The home test should not assess clarity, oxalates, urates and other important characteristics of urine. Its task is simply to identify the chorionic gonadotropin molecules.And he will do this in any case, if the level of this substance is increased in the body.
False positive results
In fact, there is a chance of a false positive test, but it is not high. Much more often women receive false negative results (this is when there is a pregnancy, but the test does not show it). If the test shows 2 strips, this means that the level of the hormone has increased, and for good reason.
However, the reasons for the striped test in the absence of pregnancy should be explained.
Hormonal disruptions caused by the presence of malignant tumors in the body can lead to a false positive result. Sometimes a slight increase in hCG is noted with uterine myoma, but with an ovarian cyst, this is extremely rare. But in this case, the test is usually weakly positive, indistinct, dim. It remains so on any day of the cycle, regardless of the phase, since the increase in the hormone is not associated with pregnancy.
False result is very likely after ovulation stimulation and IVF protocol... In both cases, the woman is injected with an injection of hCG to accelerate the maturation of eggs before ovulation, and the increased level in the blood and urine remains for a long time. That is why, in such cycles, women are not recommended to resort to home test systems in general, replacing them with a laboratory blood test for hCG in dynamics: 2 weeks after ovulation or embryo replanting, and then another week later (to assess growth rates).
Testing errors usually lead to false negative results, but it is also possible to receive a false positive test. Be careful when making diagnostics.
A test may be positive in the absence of pregnancy, if a woman had an abortion in the last cycle, suffered a miscarriage or had a frozen pregnancy. Of course, it would never occur to anyone in their right mind to plan a pregnancy in such a short time after the events described, but unplanned pregnancy is a prospect that, to one degree or another, threatens all women of reproductive age who are sexually active. The point is the residual traces of hCG. After any termination of pregnancy (medical, surgical, spontaneous), the level of chorionic gonadotropic hormone decreases gradually, and it is its traces that can be caught by the test system.
The reasons why the test is positive in the absence of pregnancy can be different, but they all need specialist advice.
There are cases when just such a timely appeal about the "striped" test made it possible to diagnose oncology in women in its early stages in time.
Non-standard situations
By the type of a positive test, of course, one cannot draw conclusions about how well the pregnancy is proceeding, for this there are other diagnostic methods, but some "oddities" cannot be ignored.
For example, a woman received a positive result before the delay. She managed to please her loved ones, her partner, she began to plan for the near future herself (renovation in the nursery, a name for the baby), but after a delay in the repeated test, the results were weakly positive or generally negative. The reason why the test system first showed two, and then one strip, may lie in a frozen pregnancy.
The fact is that the period of 3-4 weeks in the obstetric sense (this is just your last week before the start of the delay) is considered one of the most dangerous, critical in terms of the probability of freezing and stopping the development of the fetus. The reasons why the embryo suddenly stops growing and dies are very numerous and, to be honest, are not well studied by domestic and world medicine. It is believed that the reason may be insurmountable genetic abnormalities, defects that do not allow the baby after implantation to grow and develop as nature intended. The reasons can be infections, inflammatory diseases, a cold that a woman suddenly suffered, as well as the effects of paints, varnishes, alcohol, nicotine, antibiotics, etc.
After freezing, the embryo can remain in the uterus for a long time. Chorion from the moment of death does not produce new doses of chorionic gonadotropin. And for a couple of days, the level of the hormone remains quite high, and then begins to decline. When it drops to the lowest values, progesterone will fall, estrogen will rise, and endometrial rejection will begin - miscarriage. Sometimes, when women are frozen at such an early stage of pregnancy, they have no idea about their position at all, they just start menstruation after a delay, it is more abundant than usual. And if the tests were not done, then this can be perceived as a variant of the norm.
If you get negative or questionable results after a clear positive test, it is important to do a blood test for hCG over time (again after 48 hours), then visit a doctor with the results.
It is possible that the pregnancy was interrupted, and it will depend on how quickly the specialists can clean the uterine cavity whether everything will turn into sepsis and other serious consequences.
Another non-standard situation is an unchanging, weakly positive result. If the strip does not become brighter either before or after the delay, it is worth doing a blood test for hCG and visiting an ultrasound office. It is possible that the embryo is attached outside the uterus, for example, in a tube or cervix. With an ectopic pregnancy, hCG is produced, but in much smaller quantities, the level of the hormone increases extremely slowly, and therefore you will not notice the dynamics in the staining of the strip.
An ectopic pregnancy is a serious threat to a woman's life and health. It is important to diagnose it as soon as possible... This will help avoid rupture of the organ in which the ovum is fixed, bleeding, subsequent resection or ectomy of the affected organ and the development of infertility.
What to do after testing?
If you want a child, and he is welcome, then you should not rush. The earliest period when the presence of pregnancy can be confirmed by a doctor on an ultrasound is a week after the start of the delay. Usually at this time, the ovum is well defined in the uterine cavity, and after 5 obstetric weeks (this is the second week of the delay in menstruation), a tiny heart begins to beat in the baby, and this can also be noticed by an ultrasound specialist.
Ultrasound will help determine that the pregnancy is uterine, in addition, the timing can be clarified - it is in the early stages of ultrasound that it gives the most clear answer to the question, what is your exact date.
2-3 weeks after the start of the delay, you can visit the gynecologist. Obstetric pregnancy is determined as a result of a gynecological examination. It is better not to delay a visit to the gynecologist. Only a specialist can guess at such an initial time that there are some complications, the threat of interruption, problems with the endocrine background, etc.
At home, there is no way to diagnose all this. Also in Russia, women who register for early pregnancy (up to 12 weeks) are entitled to a one-time social benefit.
If pregnancy is not part of your plans and the test is positive, do not hesitate to see a doctor... 2-3 weeks after the start of the delay, an ultrasound scan should be done to make sure that the timing is accurate and that the ovum is indeed located in the uterus.
Up to 7 weeks of pregnancy, you can have a medical abortion, up to 12 weeks - a usual one with curettage of the uterus.
Anyway you need to appear in the gynecologist's office on time - before an abortion, you need to make a large list of tests in order to be admitted to it. It is possible that while you are doing the tests, something will change and you will change your mind. Midwives say that the most important day for them (almost like a professional holiday) comes when a woman who comes to the hospital to terminate a pregnancy says that she has changed her mind and leaves the child's life. Such women are escorted to the exit by all currently available medical staff.
For information on how to correctly make a pregnancy test, see the next video.
