Cheerful blonde woman talking to her doctor

FAQ - Fetal Medicine

Can the fetus hear the ultrasound?

No. The frequency of ultrasound - as its name implies, ultra-high-frequency sound - is the frequency range that can be heard by the human ear. a thousand times, so it is not audible to the human ear, and therefore not even to the fetus.

After a certain gestational age, yes. In order for someone to "hear" sound, three things are necessary: a system that captures the sound waves and transforms them into nerve impulses (in the case of humans, the pinna, auditory canal, auditory ossicles, inner ear), another that transmits these nerve processes to the brain (auditory nerve), as well as a third one that processes them in an "intelligible" form (the brain's so-called auditory cortex). Either one is missing, and that person does not hear sound in the traditional sense. The auditory bones and inner ear of the fetus develop around the 20th week of pregnancy, so it cannot "hear" any sounds before that, which does not mean that it "hears" and processes sounds in the same way as an adult does in the 30th week. since the development of the auditory cortex takes much longer. Stronger sounds (e.g. a concert), however, can already be perceived as vibrations.

No. Regarding the sounds, see the previous question regarding pressure; the fetus is surrounded by fluid /amniotic fluid/, but fluids are not compressible, so the fetus cannot be "squeezed". When the fetus starts to move during the ultrasound examination, it does so "of its own accord", not as a result of an external stimulus. It happens that the fetus does not "move" for half an hour, other times it moves continuously while the ultrasound examination is still taking place. In summary, the fetus does not feel anything from the ultrasound examination.

No. The frequency and strength used during the ultrasound examination do not endanger the fetus in any way, so - within reasonable limits - it can be performed and repeated with any frequency.

No. The fetus does not receive the food consumed by the expectant mother "one-for-one" as the expectant mother swallows, but the mother's body first breaks it down into its main components / carbohydrates (sugars), protein (amino acids), fat (fatty acids), vitamins , as well as additional elements and ions (magnesium, calcium, iron, etc.)/, and then these components pass through the placenta and umbilical cord and feed the fetus. From the point of view of the fetus, it does not matter where these important elements come from, it is another matter that a varied diet rich in vitamins and trace elements is very important and useful for the mother's body. There is also no need to worry about bacteria entering the fetus from moldy cheese, since on the one hand this is so-called noble mold, so it does not harbor pathogenic bacteria, on the other hand, these are not absorbed into the mother's body, so they do not enter the mother's blood, because that would mean a very serious, almost life-threatening condition, so-called blood poisoning. Perhaps the only foods to avoid are raw meat and eggs, but these raw foods are not unusual in our sense anyway, foods prepared during normal cooking procedures and heat treatments do not pose a danger to the fetus.

No. The substances in hair dyes and cosmetics are not absorbed either through the hair fibers or through the skin, which, if it were not so, would harm the mother's body first, not the fetus. Of course, the situation would be different if the pregnant woman drank or ate these substances, hopefully no one will think of it...

No. Ultraviolet rays - which could have a harmful effect - are absorbed in the uppermost 1-2 mm layer of the skin, so the fetus several centimeters "deep" is completely safe from them.

This should always be discussed with the attending physician. In general, it is said that if there are no complaints (there are no cramps, bleeding, etc.) there are no contraindications. The vagina is not sterile, so usually pathogens do not get there "from the outside", our larger natural waters are often said to be of drinking water quality, and the water of beaches and swimming pools is regularly disinfected. However, if you are still afraid of infection, avoid these places during pregnancy.

This should also be discussed with the attending physician. In general, it can be said that traveling by plane does not have any direct harmful effects on the fetus, it affects the body of the pregnant woman just as much as it does on the body of the non-pregnant woman (nausea, sickness, risk of thrombosis when sitting for a long time, etc.). applies to pregnancy without complaints. However, everyone must take the risk themselves, that if a problem related to pregnancy occurs thousands of kilometers away, which cannot usually be foreseen (danger of premature birth, febrile illness, bleeding, high blood pressure, etc.), then it must be solved on the spot, which can cause problems. On the other hand, for the flight - if the signs of pregnancy are already visible on the mother-to-be - the airlines can ask for a certificate that the mother-to-be has no complaints. In all cases, this must be requested from the doctor caring for the pregnant woman.

Yes. If the fetus wants to, it can open its eyes, but it does so very rarely, because it is completely dark inside the womb, no light enters there, so the fetus cannot see anything.

No. At least not during the first two trimester ultrasound examinations, because sleep is created as the end result of an extremely developed brain process, but the fetus's brain is still very underdeveloped, so it is not able to create sleep. In general, you can see that the periods of rest and movement in these fetuses usually alternate every 5-15 minutes, a sleep cycle cannot last for such a short time. In the third trimester, these cycles keep getting longer and when they stretch to several hours, the ability to sleep gradually develops in parallel with the development of the brain.

From the above, it follows that in the first and second trimesters nothing, but in the third trimester gradually more and more, even hours.

It is certain that they feel each other's movements, since the separating membrane that usually exists between them is very thin from this point of view, and only minimally reduces the strength of the movements. But it is also certain that neither of them remains indebted to the other, it is no coincidence that they say that a very close, lifelong bond develops between the twins. Only those affected can tell whether the movement of the other causes any pain to either twin, so you should ask them...

None of them. The substances in the sperm do not come into contact with the developing fetus in the womb, regardless of how the sperm enters the mother's body.

No. In the majority of cases (>90%), the start of labor falls between the 37th and 41st week, within which the time is completely independent of the weight of the fetus. If this were not the case, all babies would be born when they reach approx. 3600g weight, this is the average birth weight in Hungary today. Some fetuses are born weighing well over 4000g, others would not reach the weight of 3600g even if they were still in the womb for a month after the due date, because they are significantly below the average. No. In the majority of cases (>90%), the start of labor falls between the 37th and 41st week, within which the time is completely independent of the weight of the fetus. If this were not the case, all babies would be born when they reach approx. 3600g weight, this is the average birth weight in Hungary today. Some fetuses are born weighing well over 4000g, others would not reach the weight of 3600g even if they were still in the womb for a month after the due date, because they are significantly below the average.

It does not matter. The placenta only adheres to the "wrong" place if a smaller or larger part of it lies on the inner cervix. Its further location is irrelevant.

We never investigate this. To measure this, the baby should be lying or standing with its legs extended. Since the fetus never lies or stands like this - it simply does not have that much space, or it is not a natural pose for it - we never measure this data. The closest data to this is the so-called sitting height (abbreviated: CRL), which means the distance between the top of the head and the rear, but we will not measure this again in the future.

Definitely yes. These tests never have any contraindications, i.e. they are never unnecessary, given that they do not pose any risk to the fetus, and at the same time they work with almost 100% accuracy, i.e. the most accurate procedures of this type. At the same time, the majority of genetic abnormalities in fetuses are not inherited, but develop anew, i.e. babies from completely healthy parents will be affected, and these tests serve precisely to recognize, or rather rule out, these non-inherited chromosomal defects, thereby significantly reducing parental concern reduce it. A negative result does not mean that the test was unnecessary, but it is the "price of peace of mind..."

In the vast majority of cases, no. Apart from extreme cases, babies always take the amount that they feel comfortable with. This is even when we see the "baby reach the top of his head with his toes" because their spine and joints are still very flexible. Of course, this does not mean that certain positions and fetal positions cannot make the ultrasound examination significantly more difficult, which can even increase the examination time several times.

There is no such thing as "too much" as there is no upper limit to the normal amount of fetal movement.

Even during uncomplicated and undisturbed births, it is very common (this number can be as high as 20-25%) that the umbilical cord is wrapped around some part of the fetal body, which at the same time did not cause any complications. If this could be seen earlier during an ultrasound examination, it would only be suitable for the parents to develop a significant level of, but also completely unnecessary, concern, which is why, among other things, it is not examined.

You do not need to bring any data carrier with you to the genetic ultrasound examination, because the recordings made during the examinations will be sent online to the e-mail address you provided after the examination.

During pregnancy, the length of the umbilical cord increases continuously with the fetus from the initial few centimeters to a length of up to 1 meter, which can be measured near term. Since the umbilical cord is not visible as a straight line, but "floats freely" in the amniotic fluid, winding around the fetus, it is not possible to measure its exact length, but it is not necessary.