Can they not notice the pregnancy ultrasound. Is it possible not to see a pregnancy on an ultrasound? How long does an ultrasound show pregnancy
Among all methods for determining pregnancy, ultrasound is considered one of the most reliable and convenient. Despite the fact that modern pharmacy test strips are highly accurate and affordable, and an experienced gynecologist is able to recognize a pregnant uterus even at the earliest possible time, the last word, nevertheless, always remains with the uzist. Only according to the results of an ultrasound examination, the fact of pregnancy is considered confirmed.
Therefore, many women are perplexed when there seems to be a pregnancy, but ultrasound does not show it. In this regard, many questions arise, and sometimes even difficulties: after all, it happens that a woman needs to know about the completed conception as early as possible.
Let's see if an ultrasound can not show pregnancy if there is a delay in menstruation and the test is positive.
Why ultrasound does not show pregnancy
It is quite natural that just like that a woman will not go for an ultrasound in order to check if she suddenly became pregnant. Of course, such a decision has serious grounds. As a rule, women undergo ultrasound diagnostics for this purpose, in whom at least one or two tests showed two strips, and often their suspicions were also voiced by the gynecologist after examination on the chair. It also happens that a girl decides to visit an uzist's office based only on her own feelings: pulling pains in the lower abdomen or lower back, heaviness in the chest, nausea or a change in appetite, inexplicable irritability or weakness - such symptoms make us think about a probable pregnancy.
It is not always easy to figure out in which cases ultrasound does not show pregnancy. However, it is possible if we analyze the following factors.
Ultrasound does not show pregnancy, but no periods
A delay in menstruation is one of the very first and most likely signs that conception has occurred in the last cycle in the female body. It was the delay that our grandmothers mainly focused on when there was no ultrasound yet. But we must know that you can trust this symptom with caution. Because besides pregnancy, there are many other reasons why menstruation does not start on time or does not occur at all. These can be hormonal disruptions and other endocrine disorders, tumor formations in the organs of the reproductive system, chronic physical exhaustion, stress. Often, even such harmless reasons as a change in the climate zone or sudden weather changes lead to disruptions in the menstrual cycle.
Therefore, one should never jump to conclusions based only on the delay. Even against the background of absolute reproductive health, normal changes in the duration and course of the menstrual cycle can sometimes occur.
When ultrasound does not show pregnancy in the early stages
However, even if the delay turns out to be "real", do not rush to run to the uzist. Because if the period is still very short, then the result of the study may turn out to be unreliable, and this gives rise to unnecessary worries and misunderstandings.
In practice, there are a large number of cases when ultrasound did not show pregnancy at week 3, but after a few weeks the result turned out to be the opposite. This is not surprising.
Firstly, the fetal egg may still be too small to be seen, or even not yet reach the uterus, but is located at the time of the ultrasound in the fallopian tubes. Often, women themselves are mistaken in their calculations if ovulation moves closer to the end of the menstrual cycle, which they may not be aware of.
Secondly, for a number of reasons, a fertilized egg can land before it reaches the uterus - in this case, an ectopic pregnancy develops, which is not always possible to notice in the early stages, and it is more likely to do this when diagnosing using an intravaginal sensor.
Thirdly, what can be seen on ultrasound at 4 weeks depends largely on the sensitivity of the apparatus used. If the equipment is outdated, then at week 6 the embryo may not be recognized.
Fourthly, the experience and skills of the specialist conducting the ultrasound examination are of great importance. The human factor can never be discounted. It often happens that an inexperienced specialist takes a fetal egg for a tumor and vice versa. So the first ultrasound cannot be trusted 100%.
By the way, the cause of the error may also be an inflammatory process in the uterine cavity, in which its outer layer swells - and it becomes extremely difficult to examine a tiny spot on the endometrium.
In general, if the situation can wait at least a little, then schedule the first ultrasound no earlier than at 7-8 weeks of the intended pregnancy, so as not to be nervous and not mistaken in vain.
The test shows pregnancy, but the ultrasound does not show
But to start, of course, it is necessary to conduct a test. This is an affordable way for everyone to determine pregnancy at home, and despite the fact that mistakes also happen, pregnancy tests are quite accurate. Moreover, if the test carried out 2-3 times showed pregnancy, but the ultrasound did not show, then it is most likely that the test should be believed. Because there are many reasons why ultrasound does not see a fetal egg in the uterus, as we have already found out, and the test reagent reacts to the growth of the hCG hormone, which normally appears in a woman’s urine only a few days after conception.
Meanwhile, one cannot ignore the fact that hCG can also increase in some diseases, among which, for example, hormone-dependent tumors (and then the test will turn out to be false positive). To dispel doubts in an ambiguous situation, when the ultrasound did not show pregnancy, and the test is positive, a blood test for hCG will help.
Ultrasound does not show pregnancy, but hCG is rising
Human chorionic gonadotropin (abbreviated as hCG) is a special substance that is produced by the membranes of the developing fetus if conception has taken place in the woman's body and pregnancy has begun to develop. The level of this hormone in the blood of the expectant mother increases very rapidly during the first trimester: in the first days and weeks, its amount doubles every second day. Control over the amount and growth dynamics of hCG in a woman's blood allows you to make very accurate conclusions about whether a pregnancy develops or not. If each subsequent analysis shows higher numbers of hCG than the previous one, then we can say with confidence that the pregnancy has occurred and is developing successfully.
That is, if the ultrasound did not show pregnancy, but hCG is positive (that is, the quantitative indicators correspond to the estimated period), then it can be said with almost certainty that there is a pregnancy, and you need to undergo a second ultrasound examination. With hCG levels above 1800 mU / ml (this hormone level corresponds to approximately 3 weeks of pregnancy), doctors do not exclude the development of an ectopic pregnancy if ultrasound does not see a fetal egg in the uterine cavity.
If there is no increase in hCG, then the test will be negative, and the ultrasound will not show, since either the period is still extremely short (we are talking about several days), or the fetal egg does not develop (that is, it died), or fertilization in this cycle does not It was. By the way, there are frequent cases of biochemical pregnancy, which not all women know about.
It should be emphasized that when such uncertain situations arise that ultrasound does not see pregnancy, but the test showed, it is especially important to monitor the level of hCG in the blood in dynamics, that is, to take several tests with an interval of several days to determine whether the level is increasing HCG and whether it corresponds to the norm.
But in general, in the vast majority of cases, one should simply not force events. In fact, only in exceptional situations, confirmation or refutation of the onset of pregnancy at such an early date is urgent and cannot wait. If you're wondering if an ultrasound will show a 2-week pregnancy just to find out early, the best advice is to wait a bit. Earlier than at the 5th week of pregnancy, it is not worth doing an ultrasound at all: the accuracy of the results will be very low. At what time will ultrasound show pregnancy?
How long does an ultrasound not show pregnancy?
In conversations about how good this method is and how great it is that we have the opportunity to use it successfully today, the possibility of determining pregnancy at the earliest possible date is certainly mentioned - starting from 2-3 weeks. But here it should be understood that not any ultrasound scan can recognize any pregnancy so early. The diagnostic abilities of ultrasound diagnostics depend on a number of factors that we have already described above. And one more significant circumstance can be added to them - the location of the fetal egg in the uterus (or other organs if an ectopic pregnancy has occurred) and the anatomical features of the organs of the woman's reproductive system.
So, if the expectant mother has, for example, a bend of the uterus or the embryo is located on its back wall (even if the uterus is “normal”), then not every device and not every specialist will be able to notice the fetal egg.
In general, an ultrasound scan can show pregnancy at 2 or 3 weeks only if it is performed intravaginally (that is, a special sensor is inserted into the vagina), and if the fetal egg develops at a normal pace and is implanted in the uterus, as expected. Please note that an intravaginal ultrasound is performed only on an empty bladder so that there is normal access to the examination of the uterus.
The usual abdominal ultrasound (when the sensor is driven along the abdominal wall), provided that the doctor is highly qualified and there are no facts that make it difficult to make a diagnosis, usually shows pregnancy not earlier than the heart of the embryo begins to beat. This happens after 5-6 weeks: at this time, the future baby reaches a size of about 2-4 mm and resembles a grain of rice, which begins to take the form of an embryo, that is, it bends. Soon, this "seed" has processes - the rudiments of future limbs.
It should be said that it is more correct to raise the question not “when can I do the first ultrasound during pregnancy”, but “when is it better”. And it’s better - at 7 or 8 weeks, at least (and then only if the doctor sends you for such an examination, that is, if there are medical indications for this - suspicion of an ectopic or missed pregnancy, spotting or bloody discharge, pain in the coccyx etc.). Because practice shows that diagnostics carried out at an earlier date quite often turns out to be inaccurate and does not bring any benefit to pregnancy. Moreover, there have been cases when ultrasound does not show pregnancy even for a long time. But this is already an exception.
Experts say that it is advisable to undergo an ultrasound scan no earlier than the 10th day (or two weeks later) of the delay in menstruation.
What to do if the ultrasound does not show pregnancy
So we can draw some obvious conclusions. If you feel obvious signs of pregnancy, and especially if the test is positive, but nothing is visible on the ultrasound, then first of all you should try to guess what the term may already be (remember the dates of ovulation or the dates of "unreliable" sexual intercourse).
If it is not yet 8 weeks, then you just need to wait, after passing a second ultrasound later, but certainly on modern equipment, so as not to be nervous again.
If you need to know the situation already, then the most accurate method will be to monitor the level of hCG in the blood.
If the tests showed pregnancy, and then became negative, then the blood for hCG will certainly need to be taken and an ultravaginal ultrasound should be done again to exclude ectopic attachment of the fetal egg. Such a pregnancy will have to be terminated because it is unable to develop safely and poses enormous risks to the health and life of the woman. That is, it is very important to identify an ectopic pregnancy as early as possible. As soon as you feel signs of something wrong, you need to go to the doctor immediately.
However, we want to reassure you: almost always, when ultrasound does not show pregnancy, the reason for ignorance is too short a period. Listen to your feelings and take care of your nerves: what if everything happened? .. So, just in case, already refuse to take any medications and bad habits. And do not rush to undergo an ultrasound examination: without medical indications, you should not once again disturb the uterus during the period when embryo implantation is likely to occur.
If, in the first weeks of pregnancy, according to the results of an ultrasound scan or a blood test, it is determined that it is ectopic or frozen, then do not rush to take any action either! Repeat the study in at least two other places and undergo an additional examination (give the same blood test for hCG) to compare the results. Even doctors do not hide the fact that due to ultrasound errors, many normally developing pregnancies were interrupted. We hope that this will not affect you in any way, but this fact should also be taken into account.
Especially for - Margarita SOLOVIEVA
The moment when a woman assumes her pregnancy is very exciting. And everyone has their own reasons. But whatever they are, I want to find out as soon as possible about the result, whether it is positive or not. Nowadays, you can resort to many methods for determining pregnancy, these are all kinds of tests, and hCG analysis, and even folk methods. But perhaps the most common of them is the diagnosis using ultrasound.
Ultrasound examination (ultrasound)
One of the common methods that doctors use to determine the onset of pregnancy (starting from 3-4 weeks), as well as pathologies and female diseases.There are such types of ultrasound examination of the pelvic organs:
- Transrectal - done through the rectum. This procedure is carried out for girls who do not live sexually.
- Transvaginal - is carried out through the vagina in early pregnancy. Provides the most accurate result.
- Transabdominal - is carried out through the anterior abdominal wall (lower abdomen).
- Combined - a combination of vaginal and transabdominal ultrasound methods. Assign for a complete diagnosis.
- 3D and 4D ultrasound - with the help of these two types of studies, you can get a realistic image of the child. And let 4D still, and observe his movements and even facial expressions in real time. Shown to clarify the condition of the fetus.
The goals of ultrasound during pregnancy
The most informative way to determine the condition of the future baby, at almost all stages of development, is an ultrasound examination. In addition to monitoring the development of the fetus, using this method, you can also understand the state of the placenta, amniotic fluid, the inside of the uterus, detect deviations in a timely manner and eliminate them.
Terms of passage of ultrasound during pregnancy
Three so-called screenings are mandatory - from 10 to 14 weeks in the first trimester, the second trimester - from 20 to 24, and in the third trimester - from 32 to 34 weeks. In case of suspicion of possible violations, additional ultrasound examinations are prescribed.When you need an unscheduled ultrasound
Failures can occur throughout the entire period of pregnancy. Therefore, an unscheduled ultrasound is prescribed as problems or suspected failures arise. It is necessary to confirm or refute the diagnosis. If confirmed, promptly intervene and fix the problem.
The terms at which you can find out about pregnancy with the help of ultrasound
Transvaginal ultrasound will help you confirm the "interesting position" in the early stages. To do this, a special sensor is inserted into the vagina, on which a condom is put on. Transvaginal ultrasound is able to determine the fetal egg as early as the third week of pregnancy. During this period, the hCG level should be above 1800 units.HCG (human chorionic gonadotropin) is one of the main indicators of the presence of pregnancy and its successful course.
If, with such indicators, a fetal egg is not found in the uterine cavity, in most cases this indicates an ectopic pregnancy. But the presence of a fetal egg does not confirm fertilization (it may be empty). The embryo that is in the fetal egg should indicate the onset of pregnancy. If in the third week of pregnancy you can see only the fetal egg, then from the fifth obstetric week the heart of the embryo begins to beat, and it is during this period that pregnancy can be accurately determined. When there is no compelling reason to conduct an ultrasound in the early stages, it is recommended to perform the first study at 2 weeks of delay.
Is it necessary to conduct an ultrasound examination in early pregnancy?
As we have already said, ultrasound in the first weeks of pregnancy is uninformative. Therefore, without medical indicators (suspected ectopic pregnancy, bleeding, pain, problems with the onset of pregnancy, the threat of miscarriage, etc.), it is not recommended to carry out it.The uterus at the time of attachment of the fetal egg should be at rest. Therefore, in the early stages, you should not bother her with unnecessary interventions, in order to avoid disruption of the implantation process, and as a result, termination of pregnancy.
Are there any mistakes in determining pregnancy by ultrasound
Most often, an ultrasound examination may not notice that conception has occurred. It turns out so because of too early term. You should know that you can see the fetal egg in the uterus at about the 5th week of pregnancy, that is, at the 7th week of the obstetric period, not earlier.A very common mistake is the wrong gestational age. It is believed that ultrasound can determine the most accurate period that has passed from the moment of conception. And this is so if the study is carried out no later and no earlier than 10, maximum 11 weeks of gestation. Later, the development of the baby does not occur evenly, so it becomes more difficult to determine the gestational age by the size of the embryo.
The last most popular mistake on ultrasound is the incorrect determination of the sex of the baby. The optimal gestation period for this is 17-20 weeks. Later, space in the abdomen decreases, the umbilical cord or limbs can be located between the legs of the child and thereby interfere with seeing what gender the baby actually has.
In addition to the errors mentioned, it may also be that the ultrasound could not detect an ectopic pregnancy or embryonic death, they can also miss a genetic abnormality. Nobody is immune from this. Any suspicion of deviation must be rechecked several times.
What to do when ultrasound does not determine the presence of pregnancy?
At a very early stage, when the fetal egg is still halfway to the uterus, it is impossible to fix pregnancy using ultrasound. Then a blood test for hCG comes to the rescue. The level of chorionic gonadotropin in the blood begins to rise gradually from the first day of conception.Ultrasound examination, to date, remains the most informative and safe in monitoring pregnancy. You should not be afraid of the negative impact on the baby. The radiation is so insignificant that even frequent ultrasound examinations will not affect the baby's health in any way.
Reasons why ultrasound does not show pregnancy
Ultra-precise technology, just like people, has the ability to make mistakes. And it is not always possible to diagnose 100% pregnancy. There are cases when even at the 8th or 11th week of pregnancy, ultrasound does not detect the fetus. The pregnancy itself proceeds without pathologies. Often, the doctor in such cases gives a direction for an abortion, suspecting an ectopic pregnancy. What are the reasons for this?- The human factor - qualification of the doctor and his experience;
- Gestational age. The first structural part of the fetal egg - the yolk sac can be seen when the fetal sac is 5-6 mm in size, this is about 5 weeks, there is simply no point in going to do an ultrasound before;
- Anatomical features of the structure of the uterus - an unusual shape, due to which the device does not see the fetal egg (pregnancy is confirmed at a later date)
When a desired pregnancy occurs, all expectant mothers want to reliably make sure that the fetal egg is attached to the wall of the uterus and the formation of the unborn baby is normal. Ultrasound is considered the most reliable and convenient way to confirm a positive pregnancy test.
Despite the fact that a high-precision test strip, readily available in the pharmacy network, shows the onset of pregnancy, and a qualified obstetrician-gynecologist is able to recognize the symptoms of a "pregnant uterus", only the final ultrasound data confirms the fact of gestation. That is why, in the case when a woman believes that she managed to get pregnant, and the fetal egg is not visible on the ultrasound, future parents are perplexed.
In connection with this phenomenon, they have a question - can the diagnostician not see the pregnancy on an ultrasound scan? In our article, we want to provide information on how long it is possible to confirm the completion of the conception process, when the ultrasound scanner will allow the doctor to see the embryo, and whether it is possible not to see the pregnancy on ultrasound.
How are expectant mothers examined?
If the pregnancy test turned out to be positive, this can be confirmed by ultrasound - the diagnosis is carried out in a commercial center or in a antenatal clinic. It is important to know that an important role in obtaining reliable survey results is played by equipment with a high level of resolution and functionality, as well as the qualifications of a specialist.
Up to 9 obstetric weeks, two methods are used to examine pregnant women:
- Transabdominal - through the region of the anterior abdominal wall.
- Transvaginal - using a transducer that is inserted into the vagina.
Up to 5 weeks, the formed fetal egg is very small - its size is only about two millimeters. It is transvaginal that is considered to be an effective method for diagnosing the embryonic period - its high-frequency sensor makes it possible to get as close as possible to the uterine cavity and transfer the smallest sizes of the organs under study to the monitor screen.
The technique of examining a future mother using high-frequency waves is non-invasive and absolutely harmless - it allows the doctor to safely observe the development of the fetus
For the entire period of gestation, a woman performs at least three ultrasound scans. The examination session is short-term, the doctor tries not to hold the sensor in one place for a long time, especially during the formation of the most important organs and systems of the unborn baby.
What is seen on an ultrasound?
The main purpose of ultrasound in the embryonic period is to confirm the onset of pregnancy, this issue is especially relevant in the case of in vitro fertilization. The doctor-diagnostician has several tasks:
- Confirmation of fixation of the fetal egg in the uterus.
- Exclusion of the presence of a neoplasm in the uterine cavity, which can "mask" as pregnancy.
- Embryo viability assessment.
- Exclusion of ectopic pregnancy.
- Determination of the presence of a second fetus.
- Study of the localization of the placenta and fetus.
- Specification of gestational age.
In gynecological practice, there is one important point that all future mothers should know: the doctor measures the duration of the pregnancy period in obstetric weeks - from the first day of the last menstruation. That is why the difference between the real and obstetric term for conceiving a child is two weeks. In a woman of reproductive age with a normal menstrual cycle, recognition of pregnancy during transvaginal examination occurs no later than five weeks. If the cycle is irregular, it is difficult to determine the exact period for menstruation.
At what time is the embryo not visible on ultrasound?
Signs of a viable pregnancy are the following factors that the ultrasound scanner captures:
- the presence of a distinguishable outline of the embryo in the egg;
- listening to the fetal heartbeat;
- fixation of the slightest movements of the embryo.
For each woman, the period of bearing a child proceeds individually and it is very difficult to say exactly how long it takes for the doctor to be able to examine the fetus in the form of a dot and hear the rhythm of his heart.
In obstetric practice, there are certain normative terms for conducting ultrasound diagnostics for pregnant women. This takes into account that transvaginal scanning allows you to study the ongoing changes before transabdominal. In order for our readers to evaluate the quality of these methods, we provide a comparative table.
The beginning of contractions of the heart muscle of the future baby falls on the period from 3 to 4 weeks and it is possible to catch it only with the help of a transducer (a special narrow vaginal sensor). It happens that the uzist doctor cannot see anything in the fetal egg and recommends coming for an examination in 7-14 days.
It is the frequency of contractions of the heart muscle of the embryo that will allow the doctor to clarify the gestational age:
- at 5 obstetric weeks, the heart rate is up to 85 beats / min;
- in 6 - from 102 to 126;
- in 7 - from 127 to 149;
- in 8 - from 150 to 172;
- at 9 - 175.
If at 7 obstetric weeks no embryo parameters are observed in the fetal egg and the heart rhythm is not heard, a preliminary diagnosis of anembryony is made - the absence of an embryo in the fetal egg. However, in this case, the woman is also recommended to come for an additional ultrasound after another 7 days.
Embryo parameters
Normally, the fetal egg has an oval shape and a dark gray tint. To fully monitor the formation of the fetus on ultrasound, the following indicators are measured.
Many factors influence the clear visibility of the fetus on the monitor of the ultrasound machine, and if the embryo is not visible, do not panic - you should wait two weeks and repeat the study.
At the beginning of pregnancy, the embryo resembles the letter “C”, as it grows, the appearance changes - at 8 weeks you can already see both the head and the highlighted limbs
Why is the fetus not visible on ultrasound with a growing level of hCG?
The fetal membranes of the developing baby produce a special substance - human chorionic gonadotropin, indicating that the conception has taken place. In the first trimester, the amount of this protein-hormone in the circulating blood of a woman grows very quickly - in the first weeks, its concentration doubles every second day.
Monitoring the growth dynamics of hCG levels allows obstetrician-gynecologists to draw an accurate conclusion about the development of pregnancy.
If, when assessing the amount of this biologically active substance, an increase in its amount is observed, the doctor confirms with certainty the onset and successful development of pregnancy. Every woman wants to know about the onset of pregnancy early, but the accuracy of the ultrasound results in the second week of the delay in menstruation is very low - it is better to wait until the fifth week.
If, with positive hCG tests (in the case when the quantitative final data of the analyzes correspond to the estimated gestational age), pregnancy is not determined by ultrasound, then you need to come for an additional examination. An hCG level of more than 1800 mU / ml corresponds to the third week of pregnancy and, if an ultrasound scanner does not observe a fetal egg in the uterine cavity, the doctor assumes the development of an ectopic pregnancy.
The lack of growth in hCG levels (negative test) may indicate the fact that the development of the embryo does not occur - either it died, or the egg was not fertilized in this cycle.
Not all women know such a phenomenon as biochemical pregnancy or preclinical spontaneous miscarriage. In this case, conception occurs, the fetal egg is attached to the uterine wall, however, when the next period comes, the pregnancy is terminated.
Emphasis should also be placed on those situations where pregnancy is not visible on ultrasound, and the test is positive - monitoring the level of hCG is of particular importance, it is necessary to take a blood test several times, with an interval of several days. The final data of laboratory studies allow us to determine the compliance of the hormone concentration with the norm and its increase.
Practitioners advise future parents to try not to force events, an exception is possible only when it is necessary to confirm or deny the pregnancy as soon as possible
What to do if pregnancy is not detected during ultrasound scanning?
In the event of a situation where the uzist doctor cannot see the outlines of the embryo, and sometimes the fetal egg itself, you must try to remain calm and not succumb to false beliefs! This is possible in the absence of gestation or its period is very short to notice on the monitor. Without the presence of absolute evidence of an interrupted pregnancy, it is impossible to carry out curettage of the uterine cavity!
You should go to another clinic and re-examine - it is better to do this on expert-class equipment with high resolution. It is also necessary that the ultrasound is accompanied by blood tests for hCG levels. You may need to go through the examination several times. Future parents should make every effort so that diagnostic errors do not cost the child's life!