Any girl trying to have a child always wants to find out whether the cherished event has happened as early as possible. Fortunately, we live in the 21st century, and the arsenal of tools for early detection of pregnancy in modern medicine is already quite impressive. Impressive, but imperfect: all diagnostic methods have limitations, and no way has yet been invented to check whether conception occurred immediately, a couple of hours or days after the act of love. But, fortunately, you won’t have to languish in anticipation for long.
What is the earliest date when conception can be reliably judged, and on what day a pregnancy test will show a positive result?, and will be discussed in this article.
Determination methods. How early can you find out about pregnancy?
All methods for early diagnosis of pregnancy can be divided into two groups: visual and laboratory.
Visual tests include an ultrasound or examination by a gynecologist in a chair, and laboratory tests include determining the presence of a special hormone in the body, human chorionic gonadotropin (usually abbreviated as hCG). There are two main ways to determine the level of hCG - by taking a blood test or by doing the well-known home urine pregnancy test.
Let’s say right away that visual methods lag far behind “chemical” ones in terms of speed and accuracy of determining pregnancy. It is physically possible to see a pregnancy on an ultrasound only from the third week of embryo development, and then only with sufficient qualifications of the doctor and high quality equipment, since. the fertilized egg at this time is only a few millimeters in size. An examination by a doctor in a chair is also subjective, since certain symptoms (softening of the cervix, changes in its shape) only indirectly indicate the patient’s pregnant status.
In contrast, tests to determine hCG levels can be used as early as a week after the start of fetal development and are free of uncertainty. An increase in the level of hCG (normally absent in a non-pregnant person) starts immediately after the fertilized egg attaches to the wall of the uterus, and serves as reliable evidence that the desired event has occurred.
If we summarize the methods by which of them is the fastest, we will get something like this:
- Blood test for hCG.
- Test strip (urine) for hCG.
- Ultrasound.
- Visual examination by a doctor
And since our article is about how to determine pregnancy as early as possible, below we will talk in more detail about the level of hCG in the body of a pregnant woman and on what day it is worth taking a pregnancy test or running to the laboratory to donate blood.
How does a pregnancy test work?
The principle of operation of the pregnancy test is very simple - the reagents in the test strip change color if the level of human chorionic gonadotropin in the urine exceeds a certain level (this level is written on the test box; standard tests begin to show a second strip from 25 units of hCG. Highly sensitive tests are also available showing a second line of 10 hCG units. However, only an increase in hCG to a level of 25 or more is considered a reliable sign of pregnancy, since lower levels can be caused simply by physiological abnormalities).
On what day will a pregnancy test show a positive result?
Let's figure it out.
A positive result will appear only after a certain level of hCG is reached in the body, but how long does it take for hCG to become sufficient?
Most readers know that fertilization is possible only during ovulation. However, after fertilization has occurred, a number of events must occur, requiring a certain period of time:
The period from the moment of fertilization to the moment when the test shows two stripes is counted from the date of ovulation and consists of the period of several events:
1) Time for fertilization (up to 1 day)
2) Time to move from the fallopian tube to the uterus (up to 4 days)
3) Time for implantation (up to 4 days)
4) Time to produce a sufficient amount of hCG (up to 7 days).
First, you need to determine when ovulation occurred in this cycle. There are quite a lot of methods for determining it - from “folk” calendar methods to 100% accurate ultrasound. If you are not familiar with them, we recommend that you read the article “How to “catch” ovulation”? All about the menstrual cycle day by day."
Let's assume that you were able to figure out when ovulation occurred in this cycle. What's next?
No later than one day after leaving the ovary, the egg must be fertilized. We add 1 day to ovulation, we get 1 DPO (day after ovulation) or 15 day of the cycle (for a 28-day cycle).
3-4 days the fertilized egg moves through the fallopian tube into the uterus. It enters the uterus at 5 DPO or 19 days of the cycle.
The embryo (which at this point already has about a hundred cells) needs 3-4 days to attach to the wall of the uterus. If everything went well, then at a maximum of 9 DPO or on the 23rd day of the cycle, the embryo will attach to the uterus (by the way, a number of pregnancies are interrupted already at this stage - if a normally fertilized egg simply could not attach to the wall of the uterus. This may be one of the reasons infertility . Therefore, girls who cannot get pregnant for a long time in the absence of problems with the cycle should definitely undergo a uterine endometrial examination by a gynecologist).
So, after the embryo has attached, its outer shell (chorion, which will later become the placenta) begins to secrete the treasured chorionic gonadotropin. It is this hormone that blocks the onset of the next period.
Before implantation, its amount is approximately 0-5 units. HCG levels by day of pregnancy approximately doubles every day. That is, if the first day after implantation it is equal to an average of two units, on the second day after implantation it will be equal to 4, on the third 8, on the fourth 16, and finally, on the 5th day after implantation it will exceed the threshold of 25 units and will be equal to 32 mIU /ml. Let's remember that implantation occurred on 9 DPO (23rd day of the cycle), add 5 days to this and we get that the required concentration will be achieved on the 14th day after ovulation or on the 28th day of the cycle (that is, 1 day before the start of the expected menstruation) .
But this is the concentration of the hormone in the blood! Required concentration HCG in urine by day after implantation lags behind that in the blood by about 1-2 days. That is, the test will be positive approximately 1-2 days later than menstruation is missed.
But there are ways to “cheat” a little and find out the information earlier. Here they are:
- Buy highly sensitive tests (look at the box at the pharmacy. It should indicate that the sensitivity of the test is not 25 mIU/ml, but, for example, 10 or 15).
- Collect more “concentrated” urine. The highest concentration will be in morning urine, because... it accumulated over a long period of time - that’s why A pregnancy test should be taken in the morning. And if you drink a few glasses of water and take a test after that, the concentration of the hormone in your urine will be significantly lower.
- Take a closer look at the test. Often, at a very short time, a very, very pale second stripe is visible. If you notice such a “ghost”, it makes sense to repeat the test in a couple of days.
- Well, or just don’t do magic with urine, but go to an independent laboratory and take a blood test for human chorionic gonadotropin. One of the disadvantages of the method is that it is more expensive (the price of an hCG test in Moscow is about 500-700 rubles, and the price of a pregnancy test is about 150).
Test positivity calculator.
To simplify calculations, we have created for youhCG calculator.Enter your cycle length in the field below and the calculator will calculate, On what day will a pregnancy test show a positive result?
| 21 days - cycle length | ovulation occurred on day 7 of the cycle | conception occurred on the 8th day of the cycle | implantation occurred on day 17 of the cycle | on day 2 of the cycle, a blood test for hCG will show a positive result | on day 2-4 of the cycle the test will show a positive result | 22 days - cycle length | ovulation occurred on day 8 of the cycle | conception occurred on day 9 of the cycle | implantation occurred on day 18 of the cycle | on day 23 of the cycle, a blood test for hCG will show a positive result | on day 25 of the cycle the test will show a positive result | 23 days - cycle length | ovulation occurred on day 9 of the cycle | conception occurred on day 10 of the cycle | implantation occurred on day 19 of the cycle | on day 24 of the cycle, a blood test for hCG will show a positive result | on day 26 of the cycle the test will show a positive result | 24 days - cycle length | ovulation occurred on day 10 of the cycle | conception occurred on day 11 of the cycle | implantation occurred on day 20 of the cycle | on day 25 of the cycle, a blood test for hCG will show a positive result | on day 27 of the cycle the test will show a positive result | 25 days - cycle length | ovulation occurred on day 11 of the cycle | conception occurred on day 12 of the cycle | implantation occurred on day 21 of the cycle | on day 26 of the cycle, a blood test for hCG will show a positive result | on day 28 of the cycle the test will show a positive result | 26 days - cycle length | ovulation occurred on day 12 of the cycle | conception occurred on day 13 of the cycle | implantation occurred on day 22 of the cycle | on day 27 of the cycle, a blood test for hCG will show a positive result | on day 29 of the cycle the test will show a positive result | 27 days - cycle length | ovulation occurred on day 13 of the cycle | conception occurred on day 14 of the cycle | implantation occurred on day 23 of the cycle | on day 28 of the cycle, a blood test for hCG will show a positive result | on day 30 of the cycle the test will show a positive result | 28 days - cycle length | ovulation occurred on day 14 of the cycle | conception occurred on day 15 of the cycle | implantation occurred on day 24 of the cycle | on day 29 of the cycle, a blood test for hCG will show a positive result | on day 31 of the cycle the test will show a positive result | 29 days - cycle length | ovulation occurred on day 15 of the cycle | conception occurred on day 16 of the cycle | implantation occurred on day 25 of the cycle | on day 30 of the cycle, a blood test for hCG will show a positive result | on day 32 of the cycle the test will show a positive result | 30 days - cycle length | ovulation occurred on day 16 of the cycle | conception occurred on day 17 of the cycle | implantation occurred on day 26 of the cycle | on day 31 of the cycle, a blood test for hCG will show a positive result | on the 3rd day of the cycle the test will show a positive result | 31 days - cycle length | ovulation occurred on day 17 of the cycle | conception occurred on day 18 of the cycle | implantation occurred on day 27 of the cycle | on day 32 of the cycle, a blood test for hCG will show a positive result | on day 34 of the cycle the test will show a positive result | 32 days - cycle length | ovulation occurred on day 18 of the cycle | conception occurred on day 19 of the cycle | implantation occurred on day 28 of the cycle | on the 3rd day of the cycle, a blood test for hCG will show a positive result | on day 35 of the cycle the test will show a positive result | 33 days - cycle length | ovulation occurred on day 19 of the cycle | conception occurred on day 20 of the cycle | implantation occurred on day 30 of the cycle | on day 34 of the cycle, a blood test for hCG will show a positive result | on day 36 of the cycle the test will show a positive result | 34 days - cycle length | ovulation occurred on day 20 of the cycle | conception occurred on day 21 of the cycle | implantation occurred on day 31 of the cycle | on day 3-5 of the cycle, a blood test for hCG will show a positive result | on day 37 of the cycle the test will show a positive result | 35 days - cycle length | ovulation occurred on day 21 of the cycle | conception occurred on day 22 of the cycle | implantation occurred on day 32 of the cycle | on day 36 of the cycle, a blood test for hCG will show a positive result | on day 38 of the cycle the test will show a positive result |
And also a table of hCG by days after ovulation:
| Day after ovulation | HCG level in blood | HCG level in urine | 1 (Conception) | 0-5 | 0-5 | 2 | 0-5 | 0-5 | 3 | 0-5 | 0-5 | 4 | 0-5 | 0-5 | 5 | 0-5 | 0-5 | 6 | 0-5 | 0-5 | 7 | 0-5 | 0-5 | 8 | 0-5 | 0-5 | 9 (Implantation) | 1 | 0-5 | 10 | 2 | 0-5 | 11 | 4 | 1 | 12 | 8 | 2 | 13 | 16 | 4 | 14 | 32 (Analysis is positive!) | 8 | 15 | 64 (Analysis is positive!) | 16 | 16 | 128 (Analysis is positive!) | 32 (Test positive!) | 17 | 250 (Analysis is positive!) | 64 (Test positive!) | 18 | 500 (Analysis is positive!) | 128 (Test positive!) | 19 | > 1000 (Анализ положителен!) !} | 256 (Test positive!) |
Conclusion. On what day will a pregnancy test show a positive result?
Let's summarize all of the above.
How long before your period can you take a pregnancy test?
2-3 days before your period, if you use a highly sensitive test and morning urine. However, the most reliable results are at the end of the first week of delay.
And some of the most common questions that a girl has in connection with pregnancy tests:
There is already too much delay and the test is still negative, how long should I wait?
If the date of the last ovulation is known, and more than 21 days have passed since it, and the test is negative, then it is worth visiting a gynecologist to exclude the possibility of an ectopic pregnancy, especially if symptoms such as pain or spotting are present.
On what day will a pregnancy test show a positive result if you have an irregular cycle?
If you have an irregular cycle, count the latest date of expected ovulation. Add the length of your longest cycle to the date of your last period and subtract 14. This will be your ovulation date for that cycle. Add approximately 15-16 days to this date - by this time the test should already show the correct result.
What does it mean if in a pregnancy test one line is bright and the other is pale?
Most likely you are pregnant. Repeat the test after 1-2 days, on morning urine.
That's all. I hope we were able, if not to answer all your questions, then at least to give an idea of the mechanisms by which the mother’s body works in the early stages of pregnancy. If you have any questions, you can ask them in the comments. And if you have already found two lines on your test, then we advise you to read the article: “I’m pregnant. 5 things you should definitely do in early pregnancy”
Thirteen days after ovulation (13 DPO) and the test is negative? You shouldn’t unequivocally assume that “it didn’t work out again” and get upset in advance. At such a short period of time, not all tests for determining the concentration of the hCG hormone in the urine will show an accurate result.
From what day do you count your period as late?
Many mistakes in early pregnancy diagnosis occur only because women do not know how to calculate their menstrual cycle. You definitely need to have a special calendar. It regularly marks the days when menstruation begins and ends. Several months of working with a regular paper calendar or a special smartphone application will allow you to thoroughly study the features of your menstrual cycle. This is important for determining the moment of ovulation and delay.
The duration of a normal cycle is on average 28-30 days. Frequency is an individual indicator. Therefore, for every woman, menstruation can be either short (3 days) or long (7 days).
Your period may start a little earlier or later, and this is not a cause for concern. The moment of the onset of menstruation directly depends on external and internal factors: hormonal imbalance, stress, climate or time zone changes, poor nutrition, women's diseases and, of course, pregnancy.
To understand whether this is a delay, or the cycle has been slightly rearranged, you need to look at the calendar. It marks the end date of the last menstruation. From this day you need to count the usual duration of the cycle. For women with irregular menstruation, another option has been developed. Here the longest and shortest cycles are added together, and then the resulting figure is divided by two. For accuracy, you can calculate the arithmetic average of the last three to six menstrual cycles. By the way, all this is done independently by the mobile application.
The day of ovulation is determined in the same way. However, with an irregular cycle, it will be more difficult to understand this issue. If the number of days between menstruation is approximately the same, then it is enough to subtract 12-14 days from this figure. This will be the approximate day of ovulation. Sometimes the release of an egg from the follicle can occur closer to the end of the last menstruation or the beginning of the next. With an irregular cycle, ovulation can only be determined using special tests.
Why shouldn't you trust the results before the delay?
When will the test show pregnancy, if any? Most special strips can be used from the first day of the delay. However, you should know that there can be a negative test at 13 DPO. This is not surprising, since in a cycle lasting 28 days, it falls just on the last one. That is, in fact there is no delay yet. The concentration of hCG may not have yet reached the required minimum for the test to “react” to it.
The strips have a sensitivity of 20-25 mIU/ml. Before the delay, only expensive and high-quality pregnancy tests can recognize an interesting position. Within seven to ten days after the expected conception, strips with a sensitivity of 10 mIU/ml can determine whether a woman will become a mother in the next nine months.
Will the test show pregnancy on the 13th day after ovulation (DPO)? After all, almost two weeks have passed, and it seems that this time is enough to determine an interesting situation. In fact, this is a very short period of time. When there is no delay in menstruation yet (including at 13 DPO), a negative test should not be taken seriously. To get a reliable result, it is better to wait a few more days.
Pregnancy tests for use at home respond to the hCG hormone, which begins to be produced only after the embryo has implanted. Implantation in 18% of cases occurs at 8 DPO, in 36% at the ninth, and in 27% at the tenth. On the remaining days from 3 to 12 after ovulation, the probability of implantation is less than 10%. After attachment, the fertilized egg should begin to produce hCG, a specific pregnancy hormone (chorionic gonadotropin). For the test to accurately determine pregnancy, the hCG level must reach at least 20 mIU/ml.
"Ghost" stripe
A negative test at 13 DPO can also occur during pregnancy. It’s just that the level of the hCG hormone is not yet sufficient for the reagent to react and clearly show the second strip. But at the same time, some women see a pale line on tests. This result also cannot be considered reliable. The test needs to be repeated in a couple of days.
The line of evaporation is also called a “ghost” stripe, when there was a colored mark, but after a while it became completely invisible. The Phantom has the same width and length as the control sample. It is colored blue, pink or lilac, but is paler and barely noticeable. In some ways, the “ghost” resembles a smoky trail where there should be a brightly colored second stripe.
Negative test at 13 DPO: is there hope?
Since there is no delay on this day yet, this result does not mean that there is no pregnancy. Of course, it's hard not to worry when you've already had several unsuccessful attempts to conceive. However, you will have to wait. To worry less, it is recommended to distract yourself. The results of numerous studies prove that a woman who experiences stress reduces her chances of successfully conceiving by 12%.
In the first two weeks after implantation, the hCG level doubles every 1-2 days. If the fertilized egg entered the uterine cavity on the fourth day after ovulation, then at 13 DPO the hCG level will be only 2 mIU/l. At 5 DPO this figure will increase to 4, at the sixth - to 8, at the seventh - to 16, and at the eighth - to 32. An ultra-sensitive test will show pregnancy a week after ovulation. Normal - on the eighth day. But this is only if the woman knows exactly the day of ovulation, having determined it not by a schedule or tests, but by ultrasound. After all, the probability of attachment at the third to fifth DPO is only 0.68%. And the fertilized egg can produce hCG at different rates.
If we take average statistics, everything will go even slower. For example, implantation occurred on the eighth day after conception, and hCG increases by 2 times every two days. Therefore, at 9 DPO the hormone concentration will be only 2 mIU/ml, at 11 DPO - 4, at 13 DPO - 8, and at 15 DPO - 16. On the first day of the delay, even a high-quality sensitive test will show only a weak second line. But on the third day you will be able to admire the bright and clear line.
It happens that pregnancy develops even more slowly. It's quite normal. Conception at 10 DPO occurs in 27% of cases. Then the hCG will “grow” to 16 mIU/ml only on the third day of the delay, or at 17 DPO.
How else can you find out if pregnancy has occurred?
When will the test show pregnancy? It is possible to reliably find out whether the delay was caused by an interesting situation only on the third to fifth day of the delay. By this point, the hCG level will reach the required minimum, even if implantation occurs late and the embryo is in no hurry to synthesize the hormone. If you can’t wait to find out if you are pregnant, you can do a blood test to detect hCG at the clinic. Blood is donated from a vein in the morning on an empty stomach. The laboratory will also determine the exact gestational age.
Medication support
For some diseases or unsuccessful attempts to get pregnant, the doctor may prescribe medication. For example, Duphaston. And at 13 DPO the test was negative. Should we cancel Duphaston in this case or not? Before making a decision, the doctor will send you to a laboratory for a blood test. Further actions will depend on its result. If pregnancy is confirmed, then Duphaston is usually not canceled for some time. If conception does not take place in this cycle, then the medication should be abandoned.
There comes a moment in the life of every married couple when they decide that it’s time for them to become parents. Of course, you want to know as early as possible that pregnancy has occurred.
For this purpose, a special test is used at home. It is necessary to consider when this tool will be able to show an accurate result.
Every woman should know what a pregnancy test is, the rules for using such medications, and from what day after ovulation it is taken. This can help determine on what day of delay (and before) a true result can be obtained.
What is the device?
Any pregnancy test has the same principle of operation. Such devices contain a substance that is sensitive to the hCG hormone. It is necessary to familiarize yourself with how the research process works before using the presented tool.
Operating principle
Chorionic gonadotropin in the human body produces a fertilized egg from the moment the process of implantation of a fertilized cell into the epithelium of the uterus occurs. This occurs a few days after ovulation.
Most often, the implantation process occurs on the 7th day after ovulation. But it happens that this date shifts. Then implantation should be expected even 10–13 days after ovulation (DPO).
The hormone that indicates pregnancy rises every 24 to 48 hours. Its quantity doubles. Therefore, even the most sensitive test can show a true result no earlier than 11 DPO.
The calculations take into account the characteristics of a woman’s cycle, how long it lasts, and what day ovulation occurs. This is the only way to calculate when to do the test.
The amount of hCG increases in the urine, and on the 11th day after fertilization it is captured only by a hypersensitive pharmaceutical product. However, this happens under ideal conditions. In fact, the specifics of the cycle should be considered before testing.
To accurately determine the onset of pregnancy, all test manufacturers recommend carrying out the procedure from the moment of missed menstruation.
Susceptibility
There are 3 main types of sensitivity of drugs that allow you to determine pregnancy 2-3 days after the delay. In order for the device to be able to show a truthful answer already on the 11th day after conception, the accuracy of the medical device should be taken into account. Testers are made with different sensitivity:
- 25 mIU/ml.
- 20 mIU/ml.
- 10 mIU/ml.
Each of them is able to show pregnancy when 2–2.5 weeks have passed since DPO. If the period is too short, it is necessary to use products with a sensitivity of 10 mIU/ml. They are able to detect the presence of hCG in the urine even 11 days after conception. But there may be an error.
If the active substance of the tester reacts to a hormone concentration of more than 25 mIU/ml, then even on the fourth day of the delay an erroneously negative result is possible.
On the 9th day after ovulation, even a test that reacts to 10 mIU/ml of hCG in the urine will not determine pregnancy. A woman cannot know when the moment of implantation of a fertilized cell will occur. Therefore, the test is done no earlier than on the 11th day after ovulation. In this case, only the hypersensitivity agent (10 mIU/ml) is used.
However, all manufacturers still indicate that the earliest date when testing can be done is determined from the first day of the delay. Therefore, when wondering how long after DPO they check for the presence of the hormone in the urine, you still need to wait until the day of your expected menstruation.
Types of devices
When a woman decides to take an early pregnancy test, she is faced with a wide variety of pharmaceutical products. Their differences lie in ease of use and the size of the error.
The period from which a device can show a true result depends on its sensitivity and error. Whatever tester is chosen, it is better if its sensitivity is 10 mIU/ml. There are different types of pharmaceuticals that allow early detection of pregnancy:
- Paper strips.
- Inkjet and tablet tests.
- Digital devices.
Paper strips are the cheapest, and therefore in demand. They can be used when the period after conception is 14–15 days. The error of this method is great. He can make mistakes more often than other varieties.
At 11–12 days after ovulation, a tablet or inkjet type of device can be used. In the first case, a drop of urine is applied to the sensor using a pipette, and in the second, the tip of the device is placed under the stream. It is convenient to do such manipulations even when you are not at home. When it is not possible to collect material for analysis in a jar in the morning, this option is ideal.
Most often, sensitive devices detect a hormone concentration of 10 mIU/ml. To minimize the measurement error, you should use an electronic device. It is even able to show the period of development of new life in the belly of the expectant mother.
Even on the 12th day after conception, it will show the exact result. 4 days before your expected period (not earlier than 11 DPO), you can conduct a similar study. If the result is positive, a “+” icon will appear on the screen, and a period of time will be indicated next to it, for example, 1–2 weeks. It should be noted that the device shows how long the development of the fetus lasts from the moment of conception.
How to do testing?
To increase the reliability of the analysis, it is necessary to strictly adhere to the manufacturer's instructions.
The test should be done no earlier than 11 DPO. 3-4 days before the delay, for research it is necessary to take only morning urine and a test with a sensitivity of 10 mIU/ml. In such urine the concentration of the hormone is the highest. After a few days of delay, testing time and test sensitivity will no longer be as important.
Hands should be washed thoroughly and the container for collecting material should be disinfected. If a cardboard strip is used, it must be immersed strictly to the indicated level.
The result is assessed no later than 5 minutes from the start of the study.
In any case, it is better to repeat the study after 2-3 days. If even a faint second line is visible, you should contact a medical professional. This will make it possible to accurately determine whether pregnancy has occurred or not.
Having become familiar with the types and technology of using a home tester to determine pregnancy, every woman has the opportunity to conduct the research on her own and receive a reliable answer with a high degree of probability.
Research errors
When testing is carried out a few days before the next menstruation, you can get a false answer. Why it is better not to take a pregnancy test before a delay should be understood by every woman.
False positive response
Moreover, an incorrect positive test result is possible if a woman takes products containing hCG or certain infertility medications.
In cases where fetal development has recently been interrupted, hCG levels may not decrease quickly. This also leads to a false positive result.
False negative
But more often than not, women still get the wrong negative answer. The research tool may show a false answer if not enough time has passed since DPO.
Indeed, 11–12 days after ovulation and expected fertilization, the concentration of the hormone is not so high that it can be determined. There are a number of reasons why the device may show an incorrect negative result:
- Poor quality of the device reagent.
- When there is a threat of miscarriage.
- Pathology of the kidneys or cardiovascular system.
- Ectopic development of pregnancy.
- Testing is carried out before 10 DPO.
- The instructions are not followed.
- The study was carried out an hour after visiting the toilet or drinking a lot of liquid.
If you incorrectly calculate how much time has passed since DPO, you may not be able to detect the hormone in the urine. After 2-3 days, a repeat study is carried out.
A more accurate result before a missed period can be provided by a laboratory examination. HCG is detected in the blood 1–2 days earlier than in the urine. In any case, only a gynecologist can confirm that a woman is expecting a child after an examination.
Just a few decades ago, women learned about their pregnancy only 2-3 months after conception. And they focused exclusively on general signs in the form of delays in menstruation or a sharp deterioration in health caused by toxicosis. Today, it is much easier to find out about your “status”, because express tests to detect pregnancy have appeared on the shelves of pharmacies. But how to use them correctly? How many days after ovulation should it be performed?
- up to 15 units ml before pregnancy (after ovulation);
- from 25 units ml to 300 - in 1-2 weeks of pregnancy (average value - 140-175);
- from 300 units ml to 5000 – at 2-3 weeks of pregnancy (on average – 1800-2200);
- from 5000 units ml to 30,000 - at 3-4 weeks of pregnancy (on average - 18,000-22,000).
- dysfunction of the placenta (mostly occurs during the first pregnancy);
- threat of spontaneous abortion;
- ectopic implantation of the fetus;
- frozen pregnancy.
- multiple pregnancy;
- defects in fetal development;
- genetic predisposition to high concentrations of sex hormones (is not a disease and does not require any specialized therapy).
Show all
How does the test work?
So, a standard pregnancy test is a small cardboard strip with a special reagent applied to its surface. It reacts to the presence of human chorionic gonadotropin in the urine - the so-called “pregnancy hormone”. Why is it needed in the body? To regulate the physiological process of sex hormone synthesis. It is thanks to him that the corpus luteum, which remains in the place of the ruptured follicle, stops producing progesterone by the end of the menstrual cycle. This, in turn, is necessary to prepare the organs of the reproductive system (uterus, fallopian tubes, and in the future the placenta) for bearing a child.
It is worth noting that human chorionic gonadotropin begins to be produced in the body almost immediately after fertilization of the egg. This is why pregnancy tests can be used even before periodic menstrual bleeding should begin. So what day after ovulation can you take a pregnancy test? The optimal option is for 14-18, but this is a conditional recommendation, because it is not possible to accurately calculate the moment of release of a mature egg from the ovary, as well as the moment of its fertilization. The germ cell itself retains its ability to inseminate for 24-36 hours. That is, a total error of approximately 2-3 days should be taken into account.
Possible reasons for incorrect results
This scenario is also acceptable. They say that conception was successful, but the test strip indicates that the level of human chorionic gonadotropin is critically low (it is produced in very low concentrations even without pregnancy). What is this connected with? With the fact that in such tests the reagent has a composition in which it reacts exclusively to a high level of gonadotropin. This was done deliberately by pharmacists in order to exclude cases where the test indicated a pregnancy that in fact did not exist.
And there are also more modern methods for identifying a fertilized egg. We are talking about the so-called “jet” tests. The principle of their operation is similar to conventional paper strips, but the applied reagent is more sensitive. However, manufacturers openly indicate that such a product has a high probability of “false” results. This can also be explained by the fact that the level of human chorionic gonadotropin for each individual woman can vary dramatically.
HCG level norms
The concentration of human chorionic gonadotropin in the blood is a purely individual parameter for each woman. According to data provided by the World Health Organization, its norm is:
The hCG level gradually increases until 6-7 weeks of pregnancy, after which it stops. At the time of birth of the baby, gonadotropin in the blood varies from 4 to 18 thousand units per milliliter of blood.
Are there cases when hCG remains at a critically low level throughout pregnancy, at which even testing cannot be done? This cannot happen physically, since if the concentration of the hormone is low, the body automatically rejects the fertilized egg. In medical practice, this is called “self-abortion of the fetus in early pregnancy.” In such cases, consultation with a gynecologist and endocrinologist is necessary. It is possible that the mechanism for producing hCG is disrupted for some reason, which causes infertility.
What could a deviation from the normal hCG level indicate? When reduced it is:
But elevated hormone levels may indicate:
And also, as practice shows, a slightly increased level of human chorionic gonadotropin will be significantly increased if the pregnant woman has been diagnosed with diabetes mellitus (it doesn’t matter what type). The number of hormone units per milliliter of blood in this case can exceed the norm by almost 1.5 times. Because of this, doctors often overestimate the conditional week of pregnancy when compiling a medical record.
The most favorable days to conduct a rapid test
It is believed that it is best to take a pregnancy test after ovulation as early as 16-18 days. Then the probability of a true result is about 99.7% due to the high concentration of hCG. At this point, if the test shows pregnancy, then, most likely, the result will be confirmed during an examination by a gynecologist or after an ultrasound examination of the pelvic organs.
But on the 10th day after ovulation, the probability of a false result is approximately 60%. It is for this reason that tests are recommended to buy 2 pieces at a time, and even from different manufacturers. It is better to opt for ordinary “paper strips” rather than inkjet tests. And we should not forget that the manufacturer necessarily includes detailed instructions for use in each of them, which includes recommendations on when exactly the check should be carried out.
And if the test showed pregnancy already 3-4 days after DPO, should you trust it? There is such a thing as conditional conception. This is when ovulation was normal, and at that time the married couple often made attempts to conceive a child, although in the end nothing worked (the probability of such an outcome is about 15%). Due to the fact that a high concentration of sperm remains in the vaginal cavity over the next 3-7 days, the female body may react inadequately to this by increasing the synthesis of gonadotropin. The increase in hormone concentration will be insignificant, but this will be enough for the rapid test to react to the biochemical change in the composition of urine.
Therefore, doing a check after DPO on days 3-10 is virtually pointless. There is about a 90% chance that the test will show an incorrect result. It doesn’t matter what kind of reaction you get.
Does the time of day matter?
When to take a pregnancy test during the day: in the morning or in the evening? At what time will the result be more reliable? Doctors recommend performing the test in the morning or at least in the first half (before lunch). However, when possible, it is better to refrain from urinating and not drink any drinks with high sugar content for several hours before the test.
And if, 5-10 minutes after waiting, the second strip is only slightly visible, then this may indicate early pregnancy. It should be remembered that it is practically impossible to accurately determine the period of ovulation. The only possible option to find out at home is to measure your basal temperature and draw up a detailed graph of its changes over several months. But very rarely women do this, monitoring exclusively the duration of the menstrual cycle.
And it also happens that no matter what day after ovulation the test was carried out, but the result is still questionable. What to do in such cases? The best option is to be examined by a gynecologist, take a blood test to determine the level of hCG, and then sign up for an ultrasound examination of the pelvic organs.
In what cases is a questionable result normal?
In certain situations, you should not rely on the test result, no matter how long after ovulation the test was performed. This is due to the fact that the reagent that is applied to the test strips may give an incorrect result if there are substances in the urine that are not normal for a pregnant woman. Simply put, if its biochemical primary composition is disrupted. Against what background can this happen? This happens, for example, if a girl took some hormonal drugs in advance, or used contraceptives from the same category.
A similar situation will arise if the woman also took antibiotics. By the way, it is worth considering that they reduce the effect of taking contraceptives (almost any category). There is a huge array of factors that can ultimately affect the result of an express pregnancy test. How different will the actual result be from what the test strip shows? Such information should be obtained from the manufacturer of such products (or look for it directly in the instructions).
Also, the result of the test, which was done 10-18 days after ovulation, can be affected by various kinds of diseases of the reproductive system or the most common inflammation of the appendages. If a woman feels unwell or deteriorating, but at the same time she also has a delay, then it is better to seek help from a gynecologist as soon as possible. Due to chronic diseases in early pregnancy, a real threat arises for the unborn baby. And then it’s better to do a comprehensive check-up of the body and take blood tests to detect infections and viruses (they are still forced to undergo them when registering with a gynecologist).
In total, after ovulation you should wait at least 10 days and only then take a pregnancy test. The ideal option is for days 16-18, when the first few days of delay are conditionally determined. It is better to take the test itself several times with a break of 24-36 hours. And the final result of the tests is announced by the gynecologist based on the research performed. And it is not so important which DPO test showed a positive result, because the main thing is the normal level of sex hormones, which confirms that the pregnancy is going well.
