Is ultrasound harmful during pregnancy: the effects of ultrasound on the fetus and when to do it

April 10, 2020 Admin Home page » Ultrasound during pregnancy and childbirth Views: 164

Ultrasound research methods today are a completely common diagnostic procedure. They are prescribed to people with a wide variety of diseases and, of course, pregnant women. Almost every woman knows that she will be prescribed an ultrasound, but cases of refusal are not uncommon, even despite the doctor’s belief in safety and harmlessness. Why does this happen, what are expectant mothers afraid of and how do they justify their refusal?

The role of ultrasound studies in a woman’s life

Before the advent of ultrasound, monitoring the baby was limited to the woman regularly undergoing various tests and frequently measuring changes in blood pressure. On their basis, a rather vague conclusion was made about the general condition of the fetus and the degree of its development, without a clear definition of all its sizes.

Gynecologists most often prefer 3D ultrasound examination. Based on the results of such a study, it is always possible to determine a multiple pregnancy or abnormal location of the placenta, as well as the age of the fetus, although here, too, sometimes there are discrepancies with the actual period of up to 15 days. However, there is an opinion that frequent ultrasound during pregnancy can harm the baby. Is it true?

Is ultrasound harmful to humans?

The procedure itself takes no more than a quarter of an hour and its results are available to the doctor almost instantly. This allows you to decide what actions and how urgently should be taken in a given situation.

For this reason and due to the high information content of this diagnostic method, even cardiac ultrasound (echocardiography) is often used in clinical practice. Is heart ultrasound harmful? There are no contraindications identified for this procedure:

it does not harm either the skin or the body itself;
absolutely painless;
Since it does not have a cumulative effect, it can be repeated many times.

In other words, it is completely harmless for the body to do ultrasound frequently. This fact is very important, since there is a real opportunity to monitor the dynamics of the disease and the effectiveness of the treatment.

However, what is harmless for an adult organism can negatively affect the health of a tiny person developing under the mother’s heart.

Indications for ultrasound examination during pregnancy

There are many rumors about the dangers of ultrasound. But do they have any scientifically proven basis? How dangerous is it for the unborn child to have such an examination? Or all this is prejudice and ultrasound does not have a detrimental effect on the fetus. First you need to understand when and why this type of examination is prescribed.

Ultrasounds are performed three to four times throughout the pregnancy. The only exceptions are those cases when the mother has any pathologies that interfere with the normal development of the fetus. The first screening ultrasound is usually done before the fifteenth week. Its purpose is to confirm pregnancy, determine the number of fetuses or the presence of any pathologies. At this time, it is possible to identify such a pathology as Down syndrome. To do this, the size of the nasal bone is measured, which in such special babies is either very small or absent altogether. In the early stages, ultrasound examination is carried out only according to strict indications, since science has not proven the negative impact of ultrasound on the fetus in the same way as its absolute safety. Therefore, it is impossible to say that there is absolutely no danger for the unborn child.

The second ultrasound is scheduled at 18-20 weeks. At this time, 3D and 4D ultrasound are considered the most informative. At this time, all the internal organs of the fetus have already formed. The diagnostician must carefully assess the degree of their development. All bones of the skull are examined, as well as the main structures of the brain. Amniotic fluid, degree of maturity and integrity of the placenta are studied.

The third time an ultrasound is performed at 32-34 weeks. The exact amount of amniotic fluid is determined, and the general condition and development of the growing baby is assessed. The approximate weight of the fetus is also indicated, which is quite important for further delivery.

Research and confirmation from scientists

There are no official documents confirming that ultrasound is harmful during pregnancy. There are versions of scientists who in every possible way assure and cite dubious facts that this examination can cause:

Autism.
Epilepsy.
Developmental delays.
Speech problems.
Left-handedness.
Destruction of the placenta.
Low birth weight of the child.
DNA deformations (chromosomal abnormalities).
Epilepsy, etc.

The above was diagnosed in children whose mothers had frequent ultrasound examinations during pregnancy. Particularly dangerous is the increased depth of exposure to ultrasound. But it is not known whether this diagnosis affected the fetus or other factors.

The influence of ultrasound on the course of pregnancy

Many women are mistaken in their judgment that ultrasound is x-ray radiation, although x-rays and ultrasound have nothing in common. So is ultrasound harmful during pregnancy?

The fetus is examined using high-frequency sound waves that are inaudible to humans. And although the harm of ultrasound during pregnancy has not been proven, some experts do not exclude the negative impact of ultrasound on the fetus. That is, scientists still cannot provide any proven facts about whether ultrasound is harmful to the fetus or not.

If the examination is carried out on a conventional 2D device and, as expected, 3-4 times during the entire pregnancy, then any harm from ultrasound for the pregnant women themselves and their future babies is minimized. Doctors can often prescribe Dopplerography of the fetus without any reason, which can also have a negative impact on it.

Despite all the disadvantages, experts call ultrasound the safest research method. With the help of this study, pathologies or delays in fetal development can be identified in a timely manner. A timely ultrasound examination undoubtedly brings more benefit than harm. But this procedure should not be abused. In the normal course of pregnancy, three times is enough; additional ultrasound examinations are possible only as prescribed by a doctor for women at risk. It is dangerous to do the study more than 6 times, especially in the later stages.

Ultrasound diagnostics and introduction to it

When new discoveries are made in medicine, quite often, along with admiration, there is a certain fear, due to the fact that all new technologies need to be learned. This is similar to buying it for your home, which comes with instructions for use. The doctor prescribes medications using approximately the same principle. All packages contain an insert with instructions for use, indications, contraindications and a list of side effects. According to this rule, it is convenient and habitual for the patient to judge medications, auxiliary medical devices and diagnostics, therefore, from this point of view, ultrasound examination will be the best option to consider.

A transducer is a kind of device that captures the image of an embryo in a woman’s belly. This sensor is similar in appearance to a microphone. The transducer makes certain vibrations in the form of sending ultrasonic waves with an increased frequency. They are called ultrasonic or supersonic waves because they are elusive to the ear. These wave vibrations easily penetrate inside the pregnant woman’s abdomen, colliding with all the internal organs and body parts of the fetus located inside the womb. All organs and parts of the body differ in density. Ultrasound reaches a part of the body and is reflected, then comes back. It is precisely captured by a transducer device, through which the data is sent to the analyzing parts of the ultrasound machine.

The influence of ultrasound on fetal development

As ultrasound passes through the tissue of the mother's abdominal wall, the cellular structures are slightly internally heated. It is this heating that is considered harmful to the fetus. But scientists cannot say for sure whether ultrasound during pregnancy is harmful or not. The brain of the developing embryo is most affected.

Ultrasound during pregnancy must be performed to determine the presence of pathologies in fetal development, its growth, size and presentation, which will largely help determine the process of childbirth. It has been proven that as the fetus grows, ultrasound does less and less harm. Factors such as poor environment, bad habits and poor lifestyle of parents can cause much more harm to the child than an ultrasound examination. How many times a pregnant woman needs to have an ultrasound so that it does not cause harm to the baby, the doctor decides on a purely individual basis, based on the clinical picture of the developing pregnancy.

How does ultrasound affect the body?

In order to impartially say whether ultrasound is as harmful to the embryo as possible, it is necessary first of all to study the principle of operation of the ultrasound machine and understand why it is considered dangerous to the body. What is it?

The working area is a plate that acts as both a sensor and a receiver. Once it receives a signal, it emits sound that penetrates the tissue. The sound is at such high frequencies that the adult ear is unable to detect it.

Passing through the tissue, the sound resonates and returns back to the plate, which now works as a transmitter. The sound turns into an electrical signal, which is instantly processed by a special program embedded in the device. This is how a picture appears on the screen, which is studied by a specialist, and later seen by the patient if he receives the picture.

However, the frequencies at which sound is emitted can vary, which determines the wavelength that travels through the tissue. The volume of the image, in turn, depends on it - a long wave can even show a 4D picture, while a short wave usually produces a flat one.

Is ultrasound harmful to humans if only short waves are used? Scientific studies have shown that such diagnostics do not pose any threat to health.

Advantages of ultrasound during pregnancy

Whether ultrasound is harmful for pregnant women or not is not known for sure. The benefits of it in many cases are simply undeniable. It is this kind of examination, carried out at an early stage, that will help identify two serious problems that threaten the life of the mother and her unborn child, which need to be identified in time. It is necessary to find out whether the fertilized egg is developing in the uterine cavity and whether the placenta is growing in the form of specific bubbles instead of the long-awaited child. An ultrasound performed in the second trimester will determine whether the fetus has any congenital defects of vital internal organs. Some of them require urgent artificial delivery. Also at this time it is possible to detect pathology of the placenta, which can be most adequately corrected with medication. An ultrasound in the third trimester must be performed in order to accurately determine what the obstetric situation is and what the delivery will be accordingly.

When is an ultrasound performed?

The woman is offered to undergo the first examination for a short period of time during registration (10-14 weeks). This period is called the first trimester.

Ultrasound indications:

risk of miscarriage;
diagnosis of significant embryo deformities;
detection of pathologies during the initial development of the fetal egg;
exclusion of ectopic pregnancy;
diagnosing multiple pregnancy;
establishing the gestational age;
established disorders in gynecology in the absence of menstruation;
diagnosing hereditary diseases.

Timely detection of fetal development disorders allows future parents to decide on termination of pregnancy and avoid significant psychological stress and trauma due to the birth of a child with serious illnesses.

In the second trimester, a repeat ultrasound is required. Its duration is 20-24 weeks. At this stage, ultrasound makes it possible to discern the position of the child and the correspondence of development to the period of pregnancy, diagnose antiphospholipid syndrome, examine the placental condition, its size, localization of placental attachment and determine the sex of the child.

At this stage, the study helps doctors detect abnormalities in time and prescribe the correct appropriate treatment. Thus, when performing Doppler measurements (studying blood flow in the placental vessels), the later development of toxicosis (preeclampsia) is prevented. Prenatal diagnostics are also performed. The doctor thoroughly examines the ontogeny of the embryo and its organs “from the heels to the crown,” which allows timely detection of the development of congenital defects.

Indications for the third trimester include the location of the fetus, the study of intrauterine growth retardation (the child is born weak and underdeveloped), diagnosis of congenital defects (enlarged kidneys and enlarged ureter). Research in the third trimester helps specialists take objective measures to cure detected abnormalities.

Disadvantages of ultrasound during pregnancy

It is impossible to say for sure whether ultrasound is harmful to the fetus. In the body of the developing fetus there are small cavities that are completely filled with gas. When ultrasound begins to pass through them, they immediately burst, resulting in the formation of specific toxic free radicals that have a destructive effect on DNA. This is precisely what scientists believe is why ultrasound during pregnancy is dangerous.

In any case, it is better to conduct an ultrasound examination according to strict obstetric indications, especially for 3D and 4D ultrasound, the radiation from which is very strong.

Thus, when to perform an ultrasound examination on a pregnant woman should be determined by an obstetrician-gynecologist. Although the harm from the procedure is small, and the benefits and necessity of ultrasound are undeniable, you should not undergo this examination more often than is really necessary.

Do I need to prepare for the procedure?

So, you've signed up for an exciting procedure and want to know if any preliminary preparation is needed.

When examining the pelvic organs with a transvaginal sensor, no special preparation is required, except for basic hygiene. You must be calm and determined to have a positive result, then the baby will not flounder too actively and will allow the doctor to conduct a thorough examination.

Transabdominal ultrasound in some cases may require a full bladder. This nuance must be clarified when registering for the procedure. Bring a bottle of clean drinking water and a chocolate bar with you. Cocoa will help to move the baby and make him take a position that is comfortable for examination.

Perinatal surgery is no longer a myth

Just a decade ago, one could only dream of intervening in a child’s body before birth. In this regard, many babies died, most of whom could have been saved with the help of modern medicine. Now leading Russian clinics have equipment that allows them to carry out not only ultrasound diagnostics, but also intrauterine operations under ultrasound control.

Thus, a common malformation - a hernia of the diaphragm - causes underdevelopment of the lungs and the inability of the child to breathe independently after birth. This complication is now subject to correction: in case of a pronounced discrepancy between the size of the fetal lungs and the norm, surgery is performed under the control of an ultrasound sensor, which significantly reduces neonatal mortality.

Another reason to turn to intrauterine correction is difficulty in the outflow of urine in boys. Stenting the bladder (kidneys) improves excretory function, and then the child has every chance of being born healthy. A phenomenon such as a teratoma (vascular tumor in the sacral area) can threaten to rupture during childbirth and cause miscarriage due to excess pressure on the uterus. It is also amenable to surgical treatment.

Currently, as a result of the spread of IVF and hormonal methods of treating female infertility, cases of twins being born have become more frequent. The life of twins can be threatened by feto-fetal transfusion syndrome, which is detected by ultrasound in the second half of pregnancy. Previously, most such cases ended sadly in stillbirth or serious delays in the development of newborns. Now 80% of successful surgical interventions have a successful outcome.

Such an unpleasant phenomenon as the presence of a negative Rh factor in the mother (if it does not match the factor of the child) sometimes leads to the development of hemolytic disease of the newborn. Often only a blood transfusion can save a baby. Both diagnosis and the actual treatment of the disease are carried out using ultrasound.

Impact of sound waves on cells

There are disputes among specialists about whether ultrasound examination is dangerous and whether it is harmful in early pregnancy. Ultrasonic waves have a thermal and mechanical effect on the cells of the body. Let's consider the thermal and mechanical index.

Thermal index.

Ultrasonic waves, when interacting with tissues, lead to their heating. Naturally, the temperature inside those cells that contain a larger volume of water increases. Such heating can be harmful, especially for the fetus, whose size reaches only millimeters at the time of diagnosis.

Brain cells contain the most water. There is an assumption that it is this tissue that undergoes maximum heating after ultrasound. The consequences of this effect on the development of the embryo were not recorded.

Foreign specialists refer women for ultrasound examination only after 11-12 weeks. Previously, ultrasound was performed only if the patient had complaints. Ultrasound is not recommended for very early pregnancy without strict indications, although no harm has been recorded from it.

Mechanical index.

Ultrasound also has a mechanical effect on fetal tissue, consisting of pressure due to intensive intake. The sound pressure amplitude should not exceed 1.9. During the ultrasound examination, the effect of a sound wave of significant frequency (3.5-5 MHz) on the body is recorded.

Statement No. 4: Ultrasounds are performed only for annual medical statistics

There is a certain amount of truth in this judgment. The necessary screenings are a treasure trove of useful information for modern medicine, genetics and anatomy. Sometimes there are times when an observing specialist may make a mistake and not detect some hidden disturbances in the gradual development of the fetus. It is in such exceptional cases that such a diagnostic study will help to bypass many different problems with the development of the fetus, sometimes even saving the life of the expectant mother herself. This procedure is carried out on a voluntary basis. It is important to ensure that when conducting this research, only the most modern equipment with low radiation parameters is used.

Misconception No. 3: the baby feels bad after another ultrasound

Indeed, some babies, while still inside the mother’s womb, begin to react violently to this planned procedure. Some ardent opponents of this type of research mistakenly believe that in this way the baby is protected from harmful and dangerous waves.

Many experts argue that such active behavior of the baby in the womb is primarily associated with some excitement of the expectant mother and the gradual touch of a cold sensor.

Negative effects of ultrasonic waves

Opponents of ultrasound examination consider all possible deviations in the development of children that can be caused by ultrasound during pregnancy. Now diagnostics are carried out using third-generation ultrasound scanners. Few research centers still have old devices. The new equipment is characterized by high quality control of radiation power.

According to scientific research that experts carried out back in the 70s (using old equipment), no negative impact on the development of the embryo was recorded.

3D ultrasound: is it worth it?

For many couples, going to a pregnancy research clinic together is a regular practice. This is very important for bringing spouses closer together and the psychological comfort of the expectant mother. Watching your baby on screen is great preparation for a future father. But a person far from medicine does not have much chance of making out anything in a black-and-white wavering image.

Today there is an alternative to flat 2D imaging. 3D ultrasound does not cost much more than the traditional version, but you can see your child in great detail. This diagnosis is especially relevant for periods of 30 weeks or more, when both the hair (fluff) on the head and tiny nails on the fingers are formed. The baby sucks the loops of the umbilical cord, plays with its limbs and sensitively reacts to irritation from the abdominal sensor. An unborn child makes funny faces, blinks and makes other touching movements, which helps parents realize their new status. Therefore, this innovative technique is just for those mothers and fathers who want to get to know the little person as soon as possible, even if in absentia.