At what gestational age is the last ultrasound done. Ultrasound during pregnancy: decoding

26.08.2019

According to the decree of the Ministry of Health of the Russian Federation, during pregnancy, a woman undergoes 3 mandatory screening ultrasounds. These examinations, including the final 3 ultrasound, are prescribed to all women, even if the pregnancy is normal.

The purpose of the 3rd ultrasound examination is not only to assess the condition of the fetus, the degree of its development, the compliance of functional and physical parameters with the norm, but also to determine the state of the "womb-placenta-fetus" system. One of the main tasks of 3 ultrasound is to assess the condition of the placenta and determine the place of its attachment.

When is the third ultrasound done?

In what trimester is the 3rd scheduled ultrasound scheduled? This examination is carried out, as a rule, at the 32-34th week of gestation. With the normal development of the fetus, this time is most informative for the final ultrasound examination, assessment of the condition of the fetus, the readiness of the uterus for labor and assessment of the condition and location of the placenta.

When can the time of the ultrasound be changed? In some cases, an ultrasound examination can be attributed to an earlier time interval of the third trimester, and can be performed starting from the 30th week. If, at the final study of the third trimester, information of a dubious or alarming nature appeared in the ultrasound data, an additional ultrasound scan at a 35-38-week interval may be prescribed to a woman.

As an examination option, in the III trimester, the doctor may offer to undergo not classical dopplerometry, but a 3-dimensional ultrasound examination - 3D ultrasound. This procedure allows:

see the baby in three-dimensional image;
make a record of the motor activity of the fetus;
more accurately assess the possibility of entanglement with the umbilical cord;
in general, image quality makes diagnostic data more complete and reliable.

The third planned ultrasound is performed between the 30th and 34th weeks of pregnancy. Its main task is to control the development of the fetus and assess the state of the "womb-placenta-fetus" system.

This examination does not require special preparatory measures, including diets. Sleep well before the procedure. It is also desirable to be in a good mood and not to worry. Some signs of stress can be perceived as signs of a threat to bearing a baby.

What is examined during the final ultrasound?

When they do the third planned ultrasound, they look at both the condition of the baby and the condition of the mother's organs that ensure the vital activity of the fetus. In the third trimester, the fetus is sufficiently developed to make it possible to assess the structure of its organs and determine possible defects. The ultrasound procedure in the third trimester allows doctors to prepare for the birth of the baby, with the aim of immediate medical intervention if any pathology is determined. The development of the respiratory organs is of great importance, since the ability to breathe, and, consequently, to live, depends on the condition of the lungs. The following organs and systems are assessed:

fetometric indicators of the fetus are examined (head and limb sizes, abdominal circumference and other parameters);
the internal organs of the fetus are examined for their degree of development and possible pathologies;
the motor activity of the fetus is assessed;
the date of birth is specified;
the gender of the baby is specified;
the amount of amniotic fluid is ascertained;
the presentation of the fetus is found out;
special attention is paid to the presence of signs of fetal hypoxia, in order to take immediate measures to eliminate it;
the length of the cervical canal is established;
the umbilical cord is evaluated: the number of vessels and the level of blood flow.

At the third planned ultrasound, you can examine the child well, establish its gender, and take fetometric indicators. The doctor also assesses the condition of the umbilical cord, placenta, determines the amount of amniotic fluid

Features of the structure of the placenta in the 3rd trimester

When the third ultrasound is performed during pregnancy, most of the time of the final study is allocated for the diagnosis of the placenta, the features of its structure and condition. With normal gestation, its thickness is:

at 32 weeks - 23.5-41.6 mm;
at 34 weeks - 26.8-44 mm.

The position of the placenta is determined in order to determine the possibility of natural delivery. In some cases, the body of the placenta covers the cervix of the uterus, this condition is an indication for operative delivery. With a low position of the placenta and its attachment at a distance from the internal pharynx of less than 4 cm, it requires monitoring the condition of the pregnant woman, as bleeding may develop (both before the onset of labor and during childbirth). Warning signs are also hyperplasia or hypoplasia.

Quite often, hyperplasia (thickening) of the placenta is observed with Rhesus conflict, as a function of compensation. A change in the thickness of the placenta in any direction (both hypo- and hyperplasia) is considered as an alarming symptom. In the case of significant hyperplasia, the doctor may suspect an infectious lesion or inflammation of the placenta.

Determination of the degree of maturity of the placenta on ultrasound

Great importance in the final ultrasound is given to the readiness of the placenta for labor activity - the degree of its maturity. During the entire gestational period, changes occur in the placenta, the so-called “maturation” process takes place. Allocate 4 degrees of maturity of the placenta from 0 to III. The degree of "maturity" or "aging" of the placenta is determined by its structure and the state of the layer adjacent to the myometrium. With an increase in the "age" of the placenta, its tissue acquires a lobed structure. At stage 0, there is no division into lobules; at stage III, the entire placenta is divided into lobules.

At the moment, the most common pathology of the placenta is its accelerated "aging". That is, the III degree occurs before the 36-week period. Too early, the "aged" placenta is not able to fully fulfill its functional purpose. To improve the nutrition of the fetus, medication is prescribed.

During the examination of the placenta, other pathological changes can be detected, including calcifications (petrificates). These are calcified areas of the placenta, which have previously undergone ischemization (rapid bleeding). Many negative factors can serve as the reason for this phenomenon, including drug addiction of the mother and smoking during pregnancy. Late gestosis can also cause a similar phenomenon.

In addition to data on the condition of the fetus, the sonologist also carefully examines the condition of the placenta. This important tissue of the body must necessarily come into a state of readiness for delivery, otherwise significant difficulties will arise.

Damaged areas are not able to perform their functions, so a healthy area of the placenta has to bear a repeated load, performing the “work” of its dead areas. The placenta has significant capabilities to compensate for such losses, but nevertheless, in such a situation, constant monitoring of the blood supply to the fetus is necessary.

Functions of the placenta during ultrasound examination

Ultrasound diagnostics allows you to evaluate not only the structure of the placenta and its "maturity", but the functional state. The functional state of the placenta is detected indirectly by the blood flow in the "womb-fetus" system, the size of the fetus, and so on. Thus, the nutritional function performed by the placenta is evaluated. To study its respiratory function, it is required to conduct a rather long (up to 30 minutes) study of fetal biophysics:

number of movements;
the number of respiratory acts;
muscle tone.

When deciphering the results, the tone is judged by the posture of the fetus. Normally, the baby's limbs are bent, the hands are clenched into fists. With fetal hypoxia, his posture is relaxed.

Results of the final study

When conducting an ultrasound, an ultrasound specialist follows a certain research scheme. The doctor compares the data obtained with the existing standards. The existing norms depend on the gestational age. For example, on the 32nd week they are:

average fruit weight - 1.8-1.93 kg;
growth rate ranges from 42-43 cm;
OG (head circumference) - 28.3-32.5 cm;
Coolant (abdominal circumference) - 25.8-31.4 cm;
biparietal head size - 7.8-8.9 cm;
DB (thigh length) - 5.6-6.6 cm;
DP (shoulder length) - 5.2-6.0 cm.

When processing the results, the doctor takes into account the height and weight of the parent couple, since very large parents can expect that the baby will not be small. And if the expectant mother of a miniature married couple carries a fetus whose size is somewhat smaller than the standards, this is not a reason for panic.

If, when deciphering the results of ultrasound, diagnostically significant deviations were recorded, the obstetrician leading the pregnancy should take measures to eliminate the causes of this pathology. In such a situation, it may be necessary to undergo preventive treatment, but it may be enough to change the diet or amount of physical activity.

The health of the baby is, first of all, a healthy lifestyle for the expectant mother. The more responsibly the couple, expecting offspring, approaches the issue of conception and the process of bearing, the more likely the child is to be born strong and healthy.

Ultrasound, of course, is a very important diagnostic measure for assessing the course of gestation. Screening is carried out several times in nine months and the last, third ultrasound during pregnancy, no less significant than the first.

When do 3 ultrasounds during pregnancy

For the entire period of 9 months of gestation, a woman will have to undergo three mandatory ultrasound examinations, each of which is important in its own way, but they have slightly different goals.

The third planned ultrasound is prescribed for a period of 31 to 34 weeks. During this period, in addition to the main biometric indicators, various congenital malformations and abnormal deviations in the formation of the fetus are determined. All information on the examination is recorded in the exchange card of the pregnant woman, where the week of gestation by ultrasound will be indicated, the measurements of the baby in accordance with generally accepted standards.

3 ultrasound during pregnancy does not require special training. At this stage, a woman can eat and drink before the examination, since there is enough liquid inside the womb in order to get an excellent image on the monitor screen.

What look at 3 ultrasound during pregnancy

The last, third ultrasound during pregnancy is performed to assess the following parameters:

diagnosis of the functioning of the placenta;
determination of the state of the internal organs of the mother and child;
measurement of the main indicators of the fetus;
assessment of fetal presentation to determine the method of delivery.

The main thing that they look at 3 ultrasounds is how much the placental organ is able to fulfill its intended purpose, i.e. provide nutrition, respiration and protection of the fetus. The structure of the placenta is studied, functionality and localization are evaluated. Information about the place and density of attachment of the placenta is important only during childbirth or caesarean section.

Additionally, when studying placental indicators, the thickness of the placenta is measured at the point of attachment to the umbilical cord. With insufficient or excessive thickness, hypoplasia is diagnosed, which is characterized by an edematous reaction, an infectious process, and is often a sign of Rhesus conflict.

As the placenta forms, the temporary organ goes through all stages from maturation (birth) to aging. At 3 ultrasound check the ratio of the lower edge of the shell and the internal pharynx of the cervix. The gap should be more than 4 cm, if vice versa, then there is a threat of opening bleeding.

Quite often, when 3 ultrasounds are done during pregnancy, premature aging of the placenta occurs, as evidenced by the discrepancy between functionality and gestational age. In this case, the pregnant woman is prescribed a special drug therapy aimed at restoring utero-fetal-placental blood flow.

No less important in recent months is the assessment of the amount of amniotic fluid. Due to the fact that it is not possible to make accurate measurements, only an index is calculated by which oligohydramnios or polyhydramnios is determined. According to the results, an amnioscopy may be prescribed.

Norms of the third ultrasound during pregnancy: table

Screening examination in the third trimester involves the assessment of fetal parameters of the fetus and Doppler ultrasound diagnostics. The latter values are required to determine the intensity of blood flow, the blood circulation in the arteries of the uterus, in the umbilical cord is monitored, the contraction of the heart - systole and relaxation - diastole is studied.

There are certain terms for conducting Doppler diagnostics, which correspond to the normal index values of the LMS - the systolic-diastolic ratio:

gestation period	LMS in the umbilical artery	LMS in the uterine arteries
30-31	2,89	1,78
32-33	2,50	1,73

The interpretation of blood flow indicators implies three degrees of severity and, taking into account the results, therapy is prescribed, most often in a hospital setting. If the deviations are minor, then a healthy diet is recommended for the pregnant woman, as well as spending a lot of time in nature.

When calculating fetometric parameters, the norms of the third ultrasound during pregnancy are evaluated, which are presented in the table:

We take a week.	BPR (mm)	LZR (mm)	coolant (mm)	DBK (mm)	Weight (g)	Height (cm)
28	76	89	241	55	1319	37,2
29	78	92	253	58	1482	38,6
30	81	95	264	60	1636	39,9
31	83	97	274	62	1779	41,1
32	85	100	286	63	1930	42,3
33	86	102	296	65	2088	43,6
34	88	104	306	67	2248	44,5
35	89	106	315	69	2414	45,4
36	91	108	323	71	2612	46,6
37	93	109	330	73	2820	47,9
38	94	110	336	74	2992	49
39	95	112	342	75	3170	50,2
40	96	116	347	76	3373	51,3

The height and weight of the child is determined not only in order to assess the formation of the fetus, but also in order to understand the capabilities of a woman when giving birth to a large baby. If the mass of the baby and the circumference of the head exceed the allowable dimensions, then labor activity can take place with complications. With much smaller parameters, doctors make a diagnosis, which implies a delay in the development of the fetus.

Given what the reviews say, the planned ultrasound of the third trimester is mainly combined with a Doppler study, so it often takes a long time. Doctors try to more accurately determine the date of delivery, congenital malformations are detected by the totality of measurements, the degree of lung maturity is assessed, because this is one of the most important parameters for the subsequent life of the child.

At the last ultrasound examination, you can accurately examine the sex of the child, detect hypoxia in the fetus in a timely manner and prevent insufficient oxygen supply.

In our country, it is legally prescribed to conduct so-called screening ultrasound examinations three times during pregnancy. That is, even if a woman is not bothered by anything and her pregnancy develops within the normal range, she will have to visit the ultrasound room three times. There are no contraindications for these studies.

When is it necessary to pass the mandatory examinations? The first, second and third screenings are performed respectively at 10-14 weeks, 20-24 and from the thirtieth to thirty-fourth week of gestation. It has been proven that any risks from exposure to ultrasound are many times lower than the risks of refusing ultrasound during these periods. This article will talk in detail about the last, third ultrasound: about the goals, timing of its implementation and interpretation of the results.

By the thirtieth week, when the timing of the third screening begins, the pregnancy comes to a logical end. All the organs of the fetus have already formed, and the baby is making final preparations for the birth. Even if delivery occurs prematurely, the fetus is able to breathe on its own and survive from a full 28 weeks of gestation.

By the 34th week, the baby occupies the position in the uterus in which it will be born. And already from the thirty-sixth week, pregnancy is considered full-term. The main "task" of the child at this time is the growth and accumulation of fat mass. Another important process in the third trimester is the myelination of nerve fibers, with the help of which nerve cells increase their protection and speed of impulse conduction.

For a woman, thirty weeks is the time of the cherished maternity leave. In a pleasant bustle, it is easy to forget about the necessary visit to the doctor. But you definitely need to visit a gynecologist!

Many are interested in the question: if I went through all the studies in the early stages of pregnancy, their results are within the normal range, and I feel good - what is the final one for? How many studies are really needed? It turns out that the last screening is still necessary.

What does the third screening include?

The third ultrasound during pregnancy is the main part of the screening study, but not the only one. In addition to conventional ultrasound, late gestation is mandatory. Doppler is a special ultrasound scanning mode that allows you to evaluate blood flow in the vessels of the fetus, umbilical cord and placenta.

Another part of the screening prescribed for all pregnant women is CTG (cardiotocography). Uterine contractility and fetal heart rate are assessed. Together with Doppler measurements, CTG indicates the quality of the fetal blood flow and the condition of the placenta. By indicators of blood circulation, you can understand whether the baby has enough nutrients in the womb and whether the mother-fetus system is functioning within the normal range.

And the last study is a test of biochemical markers of the blood of the expectant mother. This procedure is not prescribed for everyone, but only for women at risk (with a mother over 35 years of age or women with a burdened obstetric and gynecological history).

Why is the third ultrasound prescribed?

Firstly, a specialist in ultrasound diagnostics carefully checks the condition of the fetus and additionally evaluates the structure of all its organs and systems. The state of the heart, blood vessels, brain, internal organs should already be checked at an earlier date during the second and third screening. But it is from the 30th week of pregnancy that the size of the fetus allows us to evaluate this thoroughly.

If deviations from the norm are found, this will affect the tactics of monitoring the patient and the delivery process for this woman. For example, if there are congenital anomalies of the valvular apparatus of the heart, a caesarean section will be recommended instead of natural childbirth, etc.

But the main part of the study will be devoted to examining the baby in connection with the upcoming birth.

According to the state of the fetal site and vessels of the umbilical cord, the doctor will assess the degree of maturity of the placenta. This will help to judge the onset of childbirth, to establish a diagnosis of preeclampsia of the third trimester.
In the case of entanglement of the fetal neck with the umbilical cord, the doctor will prescribe an observation of the process in dynamics and CTG. As a rule, this situation worries all pregnant women, and in vain: if the entanglement does not provoke fetal hypoxia (as judged by CTG), it is not dangerous! As a rule, entanglement can arise and pass spontaneously.
By the amount of amniotic fluid, the specialist diagnoses "polyhydramnios" or "oligohydramnios". This may indicate an infection of the birth canal or a frequent and dangerous disease during pregnancy, which is eclampsia.
The position and presentation of the fetus in the uterus is the main criterion for determining the tactics of labor management. If the fetus has not rolled over into a cephalic presentation by the 34th week of pregnancy, and is located with the pelvic end “towards the exit”, the doctor may suggest a planned caesarean section. Until 34 weeks, this situation is the norm.
Estimating the size of the fetus allows you to estimate its approximate weight, which also affects the management of pregnancy and the course of childbirth. The low weight of the child can tell the specialist about preeclampsia and other disorders. Exceeding normal values can change the way of delivery.
An examination of the child's cardiovascular system is an integral part of the last screening. Often, anomalies of the heart and blood vessels are detected at a later date and affect the decision on delivery that is safe for the child. The fetal heart rate is an important indicator assessed by ultrasound at all stages of pregnancy. Given the value of heart rate and its norm, the doctor draws conclusions about the condition of the child.
Examination of the cervix will rule out isthmic-cervical insufficiency that causes premature birth, but this is not always done in the third trimester.

How is the study and how to prepare for it?

As a rule, by the time of the last ultrasound, when the pregnant woman has already visited the ultrasonography room more than once, there are no questions. A day or two before the study, it is recommended to exclude from the diet all gas-producing foods (legumes, cabbage, black bread, carbonated drinks; limit the consumption of fresh vegetables and fruits).

It is highly desirable to have a normal stool on the eve of the study. If a pregnant woman is concerned about constipation, it is undesirable to do a cleansing enema without the consent of the attending physician: in the later stages, this can provoke premature birth. For this purpose, it is better to stick to a light diet, increase the amount of dairy products, prunes, and beets.

Since after 30 weeks of pregnancy, when the third screening is performed, the uterus reaches a large size and it is difficult for a woman to endure the urge to urinate for a long time, it is not necessary to "save" the bladder before the study. The procedure itself is no different from the first and second ultrasound. After questioning, the doctor asks the pregnant woman to lie down on the couch, applies a special gel to the surface of the abdomen and the sensor, and the resulting image is displayed on the screen. As a rule, at the last ultrasound, the examination is carried out only with an abdominal (external) sensor, without resorting to a vaginal one.

Deciphering the results

Thickness and maturity of the placenta

By the 30th week of pregnancy, the thickness of the placenta on ultrasound should be no more than 40 mm. With an increase in the period, its thickness increases - this is associated with the so-called aging of the placenta. The degree of maturity of the placenta is another indicator of the quality of nutrition of the fetus. The first degree should be no earlier than 30 weeks, the second - by the 35th week, the 3rd is normal after 39 weeks.

Fruit size

The doctor evaluates the size according to a special table. The diagnosis and norms will differ depending on individual indicators and on how long the study is being conducted. The abbreviations for the main indicators are given below. Whatever the value of each of the following sizes, the doctor's conclusion is always based on their totality.

BDP - biparietal fetal size

LZR - fronto-occipital size of the fetus

OG - head circumference

OC - abdominal circumference

DBK - length of the femur

DKG - the length of the bones of the lower leg

DBB - length of the tibia

DPC - length of the humerus

LCT - length of the bones of the forearm

Amniotic index (AI)

Characterizes the amount of amniotic fluid - the habitat of the fetus in the uterus. According to this indicator, the degree of full-term pregnancy and the quality of intrauterine processes are judged. The normal value of AI is from 80 to 278 mm and varies depending on the duration of pregnancy. Polyhydramnios or oligohydramnios may be an individual feature (if the results of other studies are normal), but may also indicate pathology.

Cervical length

Normally, the length of the cervical canal or cervix should not be less than 25-28 mm. But with an increase in the weight of the fetus and in the last stages of pregnancy, a decrease in this indicator is within the normal range. Before childbirth, the cervix is completely flattened. But the main criterion that is looked at at the onset of childbirth is the onset of contractions. They are usually recorded on CTG, and not with the help of ultrasound.

Conclusion

When the pregnancy is in its final stages, it is time for the final screening. The most crucial stage of bearing a child is behind, delivery is approaching. But this is not a reason to refuse ultrasound. Ultrasound is the easiest, safest and most affordable way to make sure that the pregnancy is proceeding normally, assess the condition of the baby and choose the tactics of childbirth.

Every woman looks forward to the birth of her baby. But while the baby is still in the tummy, you can already get to know him, at least from a photograph. To do this, you just need to undergo a planned ultrasound, which will also tell about the physical condition of the baby. And although there is an opinion that such a study is not very useful for the child, it is still prescribed three times for the entire period of bearing the crumbs. Why is the third done, at what time it is necessary to carry out diagnostics - this and many more useful and interesting things will be discussed further.

A few words about the procedure itself

Why is the third ultrasound during pregnancy so important? At what time it is carried out, we have already found out - at the 32-34th week. And during this procedure, the specialist also evaluates the correspondence of the lower placental edge with the opening of the cervix. This measurement is extremely important, because in this case you can first understand whether there will be a threat of bleeding during childbirth. The doctor also evaluates the thickness of the placenta itself, its attachment to the umbilical cord, and dimensions (for example, an increase in the placenta may be an indicator of an inflammatory process).

The doctor also studies the degree of maturation or aging of the placenta. This is an important factor that indicates how quickly childbirth can occur, whether there will be enough time for the baby to fully mature in the womb. Other important factors are also considered that will help the doctor determine the health status of both the mother herself and her unborn baby.

About norms

If a woman is interested in the question: “3 ultrasound during pregnancy, at what time is it better to do?” - you need to answer that everything is very individual. On average, the doctor sends a lady for such a study at the 32-34th week. But it also happens that a woman goes to the third ultrasound much earlier, because the first one was scheduled for her at the 5-6th week, and not at the 10-12th, as is usually the case. As mentioned above, the doctor sends his patients to all studies according to certain indicators. And do not worry if the doctor prescribes an additional study. After all, this procedure is absolutely not harmful to either the mother, or even more so her baby.

Development indicators

Having figured out at what stage of pregnancy the third ultrasound is done, it must also be said that the doctors enter all the indicators in a special table. Depending on these figures, specialists can also draw certain conclusions about the condition of the baby, as well as the results of future delivery. It is also important to note here that there may be deviations in the development of the crumbs (according to the table), but they do not exceed fluctuations of 1-2 weeks. During his research, the specialist makes the following measurements:

BPR, that is (measurements of the baby's head).
Coolant and OG, that is, the circumference of the tummy and head, respectively.
LZR, that is, the fronto-occipital size is measured.

The doctor should also measure the length of the forearms and shoulder of the crumbs, the bones of the lower leg and thigh bone, and the size of the nose bone is also measured.

About fetal growth retardation

When 3 ultrasounds were performed during pregnancy (at what time, we know: 32-34 weeks of gestation), the doctor can draw conclusions about whether the baby has intrauterine growth retardation. This can be evidenced by the numbers recorded by the specialist during the study. If the measurements turn out to be much less than those that should be according to the table, the doctor will first be able to make the above diagnosis. However, to confirm it, the woman will definitely be sent for additional studies, where the blood flow in the uterus, the umbilical cord itself, and the vessels of the fetus will have to be carefully studied, while the heartbeat of the baby will be carefully listened to.

It is also important to note that it is not worth trying to decipher the ultrasound indicators on your own. This is a very complex system that only qualified specialists understand. And even the necessary numbers, peeped on the pages of medical books and reference books, will not tell you everything you want to know. After all, it is also important for specialists to evaluate the correspondence of values to each other, their correlation with certain indicators.

About the latest ultrasound

As mentioned above, the third ultrasound may be the last. However, doctors often send a lady for additional research at about the 38th week of bearing a baby. And all in order to accurately determine the date of birth and with delivery.

Ultrasound examinations for every pregnant woman, of course, as well as for her doctor, are of paramount importance. According to the results of ultrasound, they determine how the child develops, whether the embryo corresponds to the gestational age. In addition, ultrasound is a wonderful opportunity for a mother to listen to the baby's heartbeat, to see it with her own eyes.

Types of ultrasound indications

Screening studies are carried out 3 times during pregnancy. For this, there are certain periods of pregnancy, namely: at 10-12, 20-22 weeks and 30-34th. The study at 26-38 weeks is carried out at the request of the mother. It is not necessary if the pregnancy is observed without complications. If, however, certain pathologies are detected in the fetus, then selective studies are indicated.

Third ultrasound during pregnancy

The most important, according to doctors, is the third study (scheduled) of the fetus, namely, 30-34 weeks, this is the period for detecting fetal defects and any abnormalities. The research process in all three cases is the same: the doctor determines the number of fetuses, their location in the uterine cavity, necessarily measures the circumference of the head and abdomen, and also necessarily the length of the child's femur.

Based on the results of the measurements, the doctor writes a conclusion, which records how many weeks the pregnancy corresponds. The size of the fetus for a certain period of pregnancy should correspond to average standards. During the study, the doctor focuses on the location of the placenta, its thickness and degree of maturity, various changes in the placenta of a pathological nature.

It looks like 3 ultrasounds made at 35 weeks of gestation

Doctors also extract valuable information from ultrasonic amnioscopy, such an ultrasound is a study of amniotic fluid. Evaluation in such a study is mainly on their number. In exact numbers, it is not possible to calculate the amount of water. The amount of amniotic fluid in medical practice is estimated by 4 linear measurements. The result of addition should normally be from 6 to 24 cm. The largest of them indicates polyhydramnios, and the smaller one indicates oligohydramnios. With an unsatisfactory condition of the fetus and placental insufficiency, as practice shows, oligohydramnios develops.

Also, important information is obtained from a Doppler study. In this study, blood flow velocity and vascular resistance are determined in large vessels of the fetus and umbilical cord arteries. The biometric ultrasound examination of such an organ as the umbilical cord is also important. Much attention is also paid to methods for predicting the entanglement of the umbilical cord around the neck of the fetus.

Cardiotocography is also interesting and effective for establishing the condition of the fetus. Also applies to ultrasound. The subject of CTG is, of course, the fetal heart rate, its variability and frequency, as well as its reactivity, in which the ability to change in relation to the degree of activity of the physical fetus is assessed.

CTG refers to very "capricious" studies. This is explained by the fact that its final results are influenced by the medications taken, the time interval preceding the meal, as well as weather factors.

Ultrasound at 30-34 weeks of pregnancy - attention to the placenta!

It has already been mentioned above that the last third ultrasound is more aimed at studying the placenta than at studying the state of the fetus itself. What caused the increased interest in this issue of specialists? The information obtained can help the delivery process, especially when a caesarean section is indicated. For this, in fact, the doctor needs to know the exact location of the placenta, as well as to which wall of the uterus it is attached.

An important indicator of the placenta is the correspondence of its lower edge directly to the opening of the cervix. To determine the likelihood of prenatal bleeding, as well as bleeding during childbirth, this measurement is extremely important. The thickness of the placenta at the place of its attachment to the umbilical cord is also important, when excessive or insufficient thickness is characterized as placental insufficiency, while a significant increase in it may be a sign of inflammation, infection. During pregnancy, it is usually detected by ultrasound, directly at 32-34 weeks.

Photograph of the third screening ultrasound taken at 33 weeks gestation

On the third ultrasound during pregnancy, it is also important to study the internal structure of the placenta, which is undergoing structural changes from the very moment of its formation. Among doctors, there are terms "ripening" and "aging" of the placenta. The terms are not entirely correct and rather conditional, which arose at the dawn of the ultrasonic era.

Experts at certain times have argued that the degree of "maturity" regarding the placenta always corresponds to specific terms of pregnancy. But, this is fundamentally not true. The placenta is divided into four degrees of maturity, which are indicated by such numbers, namely, 0, I, II, III, sometimes the letter G is added. They differ in the degree of division into lobules of the placental tissue and the state of the basal plate. Let's give an example, so the placenta G0 does not have a lobular structure, and at G III (the degree of maturity is maximum), a complete division into placental lobules is observed.

This would not be of particular interest if it were not for the frequent occurrence of premature aging of the placenta, when the II degree of its maturity is observed before the 34th week, and the III is fixed no later than the 36th week. In studies of these cases, the placenta does not fulfill its necessary functions. But this should not be a reason for discouragement. In such cases, to correct the condition, the doctor will prescribe a certain preventive treatment.

There are other diagnostic disorders in the study of the placenta. For example, placental calcification, by the way, is a fairly common problem in which necrosis of ischemic areas of placental tissue occurs. This is especially true for female smokers. In such cases, neighboring healthy areas take over the functions of damaged areas.

Note that all the results and indications for ultrasound are a real help to the doctor leading your pregnancy. They will help in the preparation of the birth canal for future childbirth, and identify risks that may be an obstacle to the normal course of childbirth.

The norms of the development of the baby and the interpretation of the results of ultrasound at 30-34 weeks of pregnancy

Doctors have special tables for determining the size of the baby in specific periods of pregnancy, with the indicators of which they compare the data obtained after ultrasound. Deviations from the table, of course, are possible and range from normal indicators - 1-2 weeks, which is not a clear sign of a fetal lag in development.

The specialist during the ultrasound makes the following measurements:

biparietal size (BDP):
fronto-occipital (LZR);
circumference of the tummy (OJ) and head (OG);
the length of the forearm and shoulder of the fetus;
length of the tibia and femur bones;
the size of the bones of the nose.

Intrauterine growth retardation (IUGR) is indicated by the doctor when the size of the fetus is significantly smaller than the accepted norms. With this diagnosis, the doctor prescribes additional studies, in which the blood flow in the uterus, in the umbilical cord, in the vessels of the embryo is determined, and the fetal heartbeat is also heard.

Photo? 3D ultrasound at 34 weeks pregnant

It is not worth deciphering the data obtained on ultrasound on your own, all the more, it would be extremely unreasonable to compare them with normative tables. Only a specialist should give an opinion on the process of fetal development and any deviations, if any.

Additional ultrasound at 35-38 weeks of pregnancy

If problems are found in a mother or baby that can negatively affect the birth process, the doctor, if necessary, will prescribe another ultrasound examination in the last weeks of the “interesting situation”. It can also be carried out at the woman's own request.

The doctor, at 35-38 weeks, will more accurately determine the date of birth, the amount of amniotic fluid and the weight of the baby, and will be able to confirm the gender of the unborn baby. In most cases, at 37-38 weeks, additional ultrasound is prescribed to determine the need for a woman to go to the hospital before giving birth.

Baby photo for memory

At 32-33 weeks and, of course, at a later date, you can take an ultrasound photo with a distinct face of the baby and his limbs. Modern technologies allow you to make a photo three-dimensional, and it will be very interesting to get a photo even before the baby is born. Finally, I would like to note that ultrasound examinations do not carry any harm to pregnancy.

The main thing is that they are carried out no more than 10 times during the entire course of pregnancy. Remember that these studies, on the contrary, are designed to identify problems in a timely manner and provide timely support and assistance.