Ultrasound examinations, which are prescribed during pregnancy, help the doctor determine whether the baby is developing correctly and whether the embryo corresponds to the gestational age. For any mother, an ultrasound is an opportunity to see her baby, listen to his heartbeat, and examine the baby’s body parts and organs.

Screening studies are carried out 3 times throughout pregnancy.

Research is routine and planned. They are usually carried out 3 times during pregnancy at 10-12, 20-22, 30-34 weeks. Also, if the mother wishes, she can undergo examination at 26-38 weeks of pregnancy; usually, if the pregnancy proceeds without complications, 3 examinations of the baby are sufficient.

In addition, if pathologies are detected in the fetus, selective studies are carried out.

Third ultrasound during pregnancy

The third routine fetal examination is the most important. It is during this period (30-34 weeks) that the doctor examines the pregnant woman to identify abnormalities and defects in the fetus.

The course of the examination during the third planned ultrasound is no different from the course of the previous ones: the doctor assesses the number of fetuses, their position in the uterine cavity, measures the size of the head circumference, abdominal circumference and length femur baby. In conclusion, the doctor writes how many weeks the pregnancy corresponds to, that is, how proportional the size of the fetus is to the average norms for given period pregnancy.

In addition, the specialist determines the location and thickness of the placenta, pathological changes in the placenta, and the degree of its maturity. Determination of quantity amniotic fluid, is one of the main directions during the study at 32-34 weeks of pregnancy. The doctor must rule out complications that could interfere with the birth process.

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

As already noted, the last third ultrasound is aimed not only at studying the fetus, but also at studying the placenta. Let's look at this in more detail and find out what is the reason for such increased interest in the placenta at these stages of pregnancy.

So, the specialist needs to accurately determine the location of the placenta, which wall of the uterus it is attached to - this information can greatly help the doctor in the process of delivery, especially if the woman has indications for a cesarean section.

Also important is the ratio of the lower edge of the placenta to the opening of the cervix. This measurement is very important to determine the likelihood of antepartum bleeding and bleeding during labor.

The width of the placenta is also measured in the place where it is attached to the umbilical cord, insufficient or excessive thickness of which, detected by ultrasound at 32-34 weeks of pregnancy, can be characterized as placental insufficiency. The internal structure of the placenta is also very important to study at the third ultrasound during pregnancy. The doctor, examining this indicator, determines the degree of “maturity” of the placenta. All these indications will help the doctor who is leading the pregnancy to determine how ready the woman’s birth canal is for childbirth and whether there are any risks that could interfere with the normal course birth process.

Norms of baby development and interpretation of ultrasound results at 30-34 weeks of pregnancy

Specialists conducting an ultrasound examination of the fetus determine the size of the baby and compare them with special tables that indicate the norms for the development of the baby at this stage of pregnancy. Sometimes deviations from the norm of 1-2 weeks are possible, which is in no way an indicator of fetal developmental delay.

It is worth noting that all generally accepted standards are conditional and you should not panic if your future baby falls a little short of certain indicators. If you are very concerned about this issue, then it is worth showing the results of the study to the doctor who is monitoring the progress of the pregnancy, he will give the necessary explanations.

During an ultrasound, a specialist measures the fronto-occipital (FOR) and biparietal dimensions(BPR), head circumference (CH) and abdomen (AB), length of the lower leg bone and length of the femur, length of the shoulder and forearm of the fetus, as well as the size of the nasal bones. If the size of the fetus is significantly smaller than normal, then in the conclusion the doctor indicates intrauterine fetal growth restriction (IUGR).

If intrauterine growth retardation is detected, additional studies are prescribed to determine the fetal heartbeat and blood flow in the uterus, in the vessels of the embryo, and the umbilical cord.

You should not try to independently decipher the data obtained from an ultrasound scan and compare them with standard tables; only a specialist will be able to give a complete and accurate conclusion about the progress of fetal development, as well as the presence of deviations, if any are detected.

Additional ultrasounds at 35-38 weeks of pregnancy

If expectant mother or the baby discovers some problems that may affect the course of the birth process, the doctor may prescribe an additional ultrasound examination for last weeks pregnancy.

A pregnant woman can conduct additional research at her own request. At 35-38 weeks of pregnancy, the doctor will be able to accurately determine the date of birth, the weight of the baby and the amount of amniotic fluid, and confirm the gender of your unborn baby. Very often, additional ultrasounds are prescribed at 37-38 weeks to determine whether a woman needs to go to the hospital before giving birth.

Photo of the baby as a souvenir

On ultrasound at 32-33 or more later you can take a photo in which the baby’s face and limbs will be clearly visible. Thanks to modern technologies future parents may even ask to take a three-dimensional photo. For any expectant mother, it is very important to get a photo of the baby before he is born.

Typically, three ultrasound examinations are performed during pregnancy. They are planned, that is, the sonologist cannot help but carry them out in order to judge proper development fetus Let's look at why and when routine ultrasounds are done and what they show.

When should an ultrasound be done?

The timing of ultrasound examinations during pregnancy is strictly regulated. And this schedule is approved by the Ministry of Health. Each medical institution can make certain adjustments to it, but in general all clinics adhere to a strict schedule of medical research.

First screening, 14 weeks

So, the first ultrasound examination during pregnancy is carried out at a period of 10 to 14 weeks.. On it, the doctor receives valuable information about the condition of the unborn child and the functioning of the mother’s organs that can support his life. If at this period the mother’s inability to bear a fetus is determined, then the question of drug interruption pregnancy.

The second ultrasound is usually done between 18 and 22 weeks. During this period, it is clearly visible whether the fetus has developmental anomalies, and whether there are pathological condition female genital organs. At this time, such pathologies can still be corrected. However, if the examination shows gross disturbances in the vital functions of the fetus, then the issue of terminating the pregnancy is also decided, this time by abortion.

The third examination is usually done at 30–34 weeks. The purpose of it is to find out the following important information:

• determining the method of delivery (during this period, for example, indications for caesarean section, which were not yet present, say, during the second examination);
• finally establish the time of birth;
• degree of development of the baby;
• determine whether the baby will need emergency help in the first minutes after birth.

You cannot ignore routine ultrasounds during pregnancy, as this is sometimes the only way to find out the degree of development of the baby.

Ultrasound screening of the third trimester of pregnancy

When can you do the examination?

Usually the fetus can be seen in the uterine cavity from the fifth day of delay of the next cycle. That is, it is visible in the third week of the gestation period. For so much early stages Pregnancy, you should visit the ultrasound diagnostic room in the following cases:

• when discharge appears, regardless of its color and quantity;
• when a woman is bothered by pain in the abdomen (in its lower part);
• when severe weakness and dizziness appear.

Such signs most likely indicate that the fertilized egg is not implanted in the uterus, that is, an ectopic pregnancy is developing.

However, recently more and more foreign clinics do not advise women to undergo the first ultrasound examination up to 10 weeks of pregnancy.

About the first ultrasound examination

As already noted, the latest period for such an examination is no more than 14 weeks. But at the same time, doing it earlier than the 10th week is also not recommended. Only if there are certain medical indications, it can be carried out much earlier.

Not only if a pathological pregnancy is suspected, the first ultrasound is prescribed earlier than the 10th week. There are approved indications for which routine ultrasound during pregnancy should be done earlier:

• if there is pain in the stomach (and not only below);
• if there is a history of spontaneous abortion or ectopic pregnancy;
• in cases where pregnancy occurred through in vitro fertilization;
• if the woman has ever had fetal malformations;
• when pregnancy occurs during stimulation of ovulation.

The positive side of such an early ultrasound examination of the fetus is that it makes it possible to detect pathologies that will be incompatible with life in the future. In these cases, an artificial termination of pregnancy is performed.

Very rarely, invasive methods of diagnosing the fetus are required. To do this, amniotic fluid is usually examined. Much less often, a biopsy of future placental tissue is performed.

When a pregnancy is terminated due to the non-viability of the fetus, the harm to the body of the mother is much less than if an abortion is performed at a later date.

What will the second ultrasound show?

Usually the period for such a study is 22, less often 24 weeks. Between the first and second ultrasound may be prescribed additional examination if a woman experiences changes in hormonal levels.

The objectives of such a survey at this time are as follows:

• accurately determine the size of the child;
• determine its gender;
• determine whether he has dangerous pathologies of the liver, kidneys, heart;
• such an ultrasound makes it possible to determine possible abnormalities in the condition of the placenta and, based on its results, carry out a more detailed diagnosis;
• allows you to determine the presence of calcium deposits in the placenta;
• find out the volume of amniotic fluid in the uterus (both an increase and a decrease in the amount are equally dangerous).

At the same time, a Doppler examination may be performed. It makes it possible to see the condition of the vessels of the uterus and placenta.

Third ultrasound

If there are no deviations in the ultrasound readings (in the second examination), then at approximately 32–34 weeks the next, third examination is performed. During this interval, a repeat Doppler examination may be performed. This is necessary to more accurately trace the dynamics of the development of the baby’s circulatory system and the mother’s placenta. In the same interval, it is very important to do a blood test for coagulation (again, to detect possible problems that may complicate the course of labor).

A repeat ultrasound is performed only when a lag in fetal growth is detected, as well as if there are any problems in the bloodstream. In this study, ultrasound shows:

• congenital malformations (their detection is no less important than in the second trimester);
• hydronephrosis of the kidney (that is, when fluid accumulates in the renal pelvis);
• position of the fetus (head presentation is normal, and if the baby is in an uncomfortable position, the issue of premature delivery can be decided to save his life);
• severe fetal malformations (artificial termination of pregnancy and childbirth);
• the size of the child (the doctor assesses how they compare with the age norm);
• location of the placenta;
• the position of the baby's head (sometimes it can turn as much as 180 degrees).

Diagnostic methods

There are two ways to conduct ultrasound diagnostics: transabdominal and by inserting a sensor into the vagina.

Performing transvaginal ultrasound during pregnancy

In the case of a vaginal examination, a condom is placed over the ultrasound probe. This is done mainly for hygienic reasons. Next, it is inserted into the woman’s vagina. Because the sensor is closer to the uterus, the doctor can better see the fetus, the uterus, its tissues and the placenta. This method of examination is most often used in the early stages. It is advisable to keep the bladder empty.

In the case of a transabdominal examination, a small amount is applied to the woman's abdomen. clear gel. This is done to ensure that there are no air bubbles between the skin and the sensor, which impair visualization. The doctor moves an ultrasound probe over the abdomen to examine the fetus and uterine tissue.

There is no need to make any additional preparations before such studies.. The only requirement is to maintain hygiene of the skin and external genitalia. There is no need to adhere to a diet or drinking regime before these types of examinations.

Why do a 3D study?

Currently, three-dimensional ultrasound is becoming increasingly widespread. Many parents believe that it is more accurate and correct. In fact, this is just an additional diagnostic examination. Sometimes a specialist who has a regular two-dimensional ultrasound machine, can examine the fetus and placenta and draw the necessary conclusions.

Such research attracts future parents primarily because it allows you to see the image in three projections. It will look on the screen as three-dimensional and very High Quality. It also allows you to record the child’s movements on electronic media. And they can be recorded on a disk or other electronic media.

Is such research harmful?

It is known that a planned ultrasound scan is practically unavoidable, since all women undergo it. Provided that the pregnant woman follows all the doctor’s instructions and advice and is registered on time, the number of such examinations is at least three. It happens that more such ultrasounds need to be done.

All studies performed using ultrasound are absolutely harmless. There is no evidence today that ultrasound is harmful and that it leads to any consequences for the female body.

Moreover, the woman does not feel any discomfort during the procedure. Ultrasound is completely harmless to the baby, as is touching the skin of the sensor (or placing it in the vagina). The intensity of such radiation is so low that it does not cause any chromosomal changes and does not affect living cells of the fetus.

However, pregnant women are not recommended to abuse such examinations on their own initiative. This means that you cannot do them whenever you want. For such a harmless examination as ultrasound, there are still deadlines and indications.

Should such research be neglected?

Of course, on different dates pregnancy, ultrasound examination helps to detect fetal pathologies, and at the most early stages. In many cases, it helps to avoid many adverse consequences for the woman. And you shouldn’t give it up. Moreover, it is harmless to the mother and her unborn child.

Every woman should undergo at least three ultrasound examinations. The doctor also decides when unscheduled diagnostics are needed. If he insists on conducting an unscheduled examination, there is no need to ignore it, since the child’s health may depend on it.

It is an ultrasound examination that helps the child to be born healthy and the mother to be happy.

Ultrasound waves began to be used in medical diagnostics to obtain information about organs and tissues. Simply put, an ultrasonic device consists of two parts: a wave generator and a sensor. The generator sends high-frequency sound waves, inaudible to the human ear, and then receives the reflected echoes and converts them into an image. Since the tissue density is not the same, a special screen creates a picture that is clear to the doctor about what is happening inside the body.

Since 1960, ultrasound has been used to study the condition of the fetus during pregnancy. The method turned out to be so successful that by the end of the twentieth century, ultrasound became a mandatory part of the general examination of all pregnant women.

For the effectiveness of ultrasound, the qualifications of the specialist, equipment and uniform timing of the procedure are of great importance.

Three screening examinations are considered mandatory at the recommended times for everyone when an ultrasound scan is performed during pregnancy:

1. The first diagnosis is prescribed from 10 to 14 weeks after the expected conception. At this time, gross malformations are determined. The procedure also makes it possible to calculate the timing of pregnancy.
2. carried out at 20-24 weeks. By this time, most systems and individual organs have been formed, and the anatomical structure is clearly visible.
3. The last scheduled ultrasound occurs between the 32-34 week intervals. It is recommended for all women, even if everything is normal and the child is developing without any abnormalities. The main task at this stage is to assess the condition of the placenta and determine how the fetus is located in the uterine cavity.

Scheduled ultrasounds during pregnancy: how many times and at what dates

Ultrasounds are routinely performed three times. However, the doctor may prescribe additional ultrasound examinations to clarify the results of previous diagnostics or if the pregnant woman complains of poor condition. Each of the three mandatory screenings is done to evaluate certain parameters.

First examination

During this procedure, starting from , gross developmental disorders and risks of chromosomal pathologies are diagnosed through measurements of the cervical fold (nuchal translucency). Where the chorion (future placenta) is located is carefully studied, its structure and the presence of detachment are assessed. The first ultrasound determines the time of conception.

Second ultrasound during pregnancy: at what stage is it best to do it?

The anatomical structure of the baby is most fully determined during the period from 20 to 22-24 weeks. By this time, almost all organs have been formed, and echography can be used to examine whether they are developing correctly. Particular importance is paid to the work and structure of the heart muscle.

Before the 20th week, echography is prescribed if certain hormones are abnormal and if the woman is over 35 years of age.

Third ultrasound during pregnancy: at what stage and why is it done?

During this time, it is possible to diagnose the degree of fetal development and its location in the uterus. The third examination is mandatory for all expectant mothers. If pregnancy is normal and the results of other tests are good, then a third echography is prescribed from the 32nd week. If possible violations are suspected, the procedure is carried out earlier - from 30 weeks. To monitor the presence or absence of abnormalities in dynamics, the diagnosis can be carried out again at 35-38 weeks.

Diagnostic features

Ultrasound examination is a non-invasive method, that is, not associated with damage to human skin or tissue. It allows you to monitor the growth, condition and structure of the fetus, and effectively diagnoses intrauterine developmental defects. Examinations of the baby in the womb are carried out in two ways:

• transvaginal (the sensor is inserted inside) - a particularly informative method, since there is less different tissue between the sensor and the child, which allows you to get a more accurate signal;

• the usual abdominal one (the sensor is placed on the stomach).

How to confirm pregnancy using ultrasound

Using ultrasound, you can not only determine conception, but also find out the place of attachment of the embryo (in the uterus or outside it); see whether pregnancy is developing as expected or not. For a more accurate result, the doctor may not prescribe the usual examination procedure through the abdominal wall, but recommend access of the sensor through the vagina (transvaginal). Transvaginal examination helps to better visualize internal processes, more accurately predict the due date, and determine the number of fetuses in the uterus.

By week 8, the study determines with high probability the motor activity of the fetus and its subsequent viability.

How to prepare for diagnosis

In the first trimester, in some cases it is recommended to carry out the procedure with a filled bladder. To do this, you need to drink half a liter of water 30 minutes before the examination. Your doctor will tell you whether you need to drink water or not.

There is no need to do anything special before the second and third screening. A woman can eat as usual, and there are no regulations regarding the degree of bladder fullness.
But it is better to exclude foods that cause gas formation a day or two before the examination, since the accumulation of gases in the intestines can affect the accuracy of the result.

Just in case, bring a diaper to your appointment to cover the couch and wipes to remove any remaining gel.

Fetal size chart by ultrasound

The table shows the average sizes and weights for each week of pregnancy.

Investigation for suspected ectopic pregnancy

Availability and location ovum determined using the vaginal method of examination at 5 weeks, and using the usual method at 7 weeks. If the ultrasound examination shows normal attachment of the egg in the uterine cavity, then there is nothing to worry about.

Alarm signals will be: fluid in the uterine cavity, increased size of the appendages, dilated fallopian tube. In this case, doctors say they suspect an ectopic pregnancy.

To confirm the diagnosis, an analysis is performed to measure the level of the hCG hormone. If the hormone level is above 1800 IU/l, and the fertilized egg is not detected during an ultrasound examination, then the likelihood of an ectopic conception is very high.

In what cases is additional research necessary?

Even before the first screening test, a woman can undergo an ultrasound examination to confirm that conception has occurred.

In the second trimester, an additional examination is prescribed approximately 10 days after the planned one, if the doctor has any doubts. This is done to see how the fetus develops over time, whether there is really cause for concern or not.

In the last trimester, another echography is prescribed in case of any deviations from the normal course, in order to assess possible risks, for example, when the umbilical cord is entangled.

Did you know? If the examination reveals slight deviations in size or weight from the norm, this is not a cause for concern, since each child develops at his own pace. In addition, height and limb length indicators depend on the genetic properties of both parents.

Additional examination may be prescribed at any time for the following manifestations:

• nagging pain localized in the lower abdomen;
• bloody discharge from the genitals;
• if the size of the fetus does not correspond to the gestational age;
• any abnormalities in the location of the placenta;
• if there are two or more babies in the uterus;
• malpositioned fetus.

A woman herself may want to undergo a relatively new additional procedure - three and four-dimensional ultrasound. The result of such an examination will be a three-dimensional image of the baby and video recording of his movements. How many such ultrasounds are performed during pregnancy is a matter for each couple, but the clearest three-dimensional images are obtained between 22 and 32 weeks.

Decoding the results

The results of the examination are recorded in a special protocol. The protocol forms differ for each of the three studies. So, in the first trimester the main points include:

• estimated date of birth based on the results of the study;
• whether the size of the fetus from the coccyx to the crown corresponds to the gestational age determined by the last menstruation.
• heart rate: normally this indicator corresponds to 150-178 beats per minute;
• the thickness of the collar space, which is used to judge chromosomal abnormalities;
• how the chorion is located (on one of the uterine walls or on the fundus of the uterus). Heterogeneity of the structure may indicate infection;
• structural features of the uterus and appendages.

In the second trimester the following is recorded:

• anatomical dimensions in mm;
• presentation (cephalic or pelvic);
• where the placenta is located, its thickness, structure; whether her maturity corresponds to the gestational age;
• note the amount of amniotic fluid;
• record the detection or non-detection of congenital developmental defects.

During the third trimester, look for the following:

• once again clarify the location of the child in the uterus and the condition of the umbilical cord;
• determine the degree of development of the baby’s organs and systems;
• assess the size ratio (length of limbs, whole body, head circumference, etc.);
• identify developmental defects in which the baby will require medical intervention immediately after birth;
• assess the frequency with which the baby moves;
• specify the gender of the child;
• assess the thickness and maturity of the placenta. The optimal thickness is considered to be from 25.5 to 44 mm, and maturity of the second degree.

Video about whether ultrasound diagnostics are harmful

Dr. Komarovsky answers the question of how ultrasound examination affects the fetal nervous system and what the real harm may be from frequent echographic procedures.

According to medical estimates, ultrasound diagnostics is a fairly informative and safe method. But still, this is a medical procedure, therefore, the question of “how often can an ultrasound be done during pregnancy” should be discussed with your doctor.

Write how many times during your pregnancy did you undergo this diagnostic procedure, and would you recommend an ultrasound examination to other women?

Ultrasound during pregnancy is an integral part prenatal screening. They are regulated by Order of the Ministry of Health of the Russian Federation No. 572 dated November 1, 2012 (Appendix No. 5).

Timing of ultrasound

Routine ultrasound during the gestation period is carried out three times, the timing of which is optimal for identifying abnormalities of fetal development, pathology of the placenta and internal genital organs, and confirming the timing of pregnancy. If there are indications, an additional ultrasound is prescribed, regardless of the stage of pregnancy.

Deadlines for mandatory ultrasound examination:

• Ultrasound in the 1st trimester - 11-14 weeks;
• Ultrasound in the 2nd trimester - 18-24 weeks, most often performed from the 21st week;
• Ultrasound in the 3rd trimester - 30-34 weeks, including Doppler measurements.

The purpose of ultrasound by trimester

The main purpose of prenatal ultrasound screening is to obtain information to provide timely and optimal prenatal care, and in the later stages, to resolve issues about further prolongation or termination of pregnancy and choose the method of optimal delivery.

Indicators that are assessed during ultrasound in the first trimester:

• confirmation of intrauterine or ectopic pregnancy;
• number of embryos in the uterus;
• measurement of heart rate (heart rate), possible from 5-6 weeks;
• identification motor activity unborn child (possibly from 8-9 weeks of pregnancy);
• identifying signs of a threatened miscarriage;
• measurement of the coccygeal-parietal size (CTP) - precedes the fetal growth rate;
• measurement of the width of the cervical-collar space (diagnosis of gross malformations of the fetus, Down syndrome);
• presence/absence yolk sac and its diameter;
• location of the chorion (future placenta) - in the fundus of the uterus or at the internal os of the cervix;
• chorion structure;
• assessment of the uterine appendages (size, presence of cysts, developmental anomalies);
• assessment of the structure of the uterus (developmental anomalies, myomatous nodes and tumors).

Indicators that are assessed in the second trimester:

• the growth and development of the fetus is assessed, its compliance with the gestational age (detection of a large fetus or intrauterine growth retardation);
• examination of all organs and systems of the fetus (fetal anatomy);
• identification of developmental defects;
• fetometry (assessment of the main dimensions): biparietal, fronto-occipital size, cephalic index, head and abdominal circumference, length of tubular bones (femur, tibia, forearm);
• study of the placenta - its location, size, presence of calcifications, degree of maturation, presence of presentation;
• amount of amniotic fluid and amniotic fluid index (oligohydramnios and polyhydramnios);
• number of umbilical vessels (normally there are 3);
• cervical length (detection of isthmic-cervical insufficiency) - normal 3-4 cm;
• gender of the child (important for some genetic diseases).

Assessment of indicators of the third trimester:

• fetometry and fetal weight, fetal growth from the previous ultrasound (adequate, accelerated, slow or absent);
• fetal presentation (decision of the issue of delivery);
• developmental defects that are diagnosed late;
• addressing the issue of correction of developmental defects (immediately after childbirth or later);
• the presence of knots and entanglement of the umbilical cord;
• degree of placental maturation, localization, structure, detection of fetoplacental insufficiency;
• examination of the uterus, assessment of the consistency of the suture on the uterus (if there have been surgical interventions before);
• measuring the length of the cervix, assessing the birth canal before childbirth.

The need for an extraordinary ultrasound is due to the following indications:

• pregnancy complications (threat of miscarriage, spotting);
• suspicion of an ectopic (ectopic) or frozen pregnancy;
• exposure to unfavorable factors during gestation (previous infectious processes, etc.);
• uterine fibroids and ovarian tumors;
• miscarriage, isthmic-cervical insufficiency.

Methods

Ultrasound during pregnancy is performed in two ways: transvaginally and transabdominally. Carrying out transvaginal ultrasound examination applies only in the first trimester. No special preparation is required for the study. A condom is placed over the transvaginal probe, and then the probe is inserted into the woman's vagina (she lies on a couch with her legs bent and spread). During the examination, the doctor moves the sensor slightly to better visualize the uterus and embryo.

With transabdominal ultrasound, the examination is carried out through the anterior abdominal wall (the woman exposes the abdomen). A special gel is applied to the skin of the abdomen and the sensor is moved along the abdominal wall. When examining in the first trimester, a full bladder is required for better visualization of the uterus and appendages and a diet on the eve of the ultrasound is required, excluding foods that cause gas formation.

Some studies during pregnancy

Sometimes an ultrasound of the pelvic organs helps to understand whether a woman is pregnant. It is in the small pelvis that the uterus is located, where the chorion is fixed, as well as its appendages. Ultrasound can detect both normal and ectopic pregnancy.

This ultrasound is performed after 1-2 weeks of missed period. Pregnancy can be detected not only by the detection of a fertilized egg, but also by an increase in the thickness of the endometrium to 25 mm, as well as a large corpus luteum.

At normal course During pregnancy, 3 scheduled ultrasounds are performed: at 10-12, 20-22 and 30-36 weeks. If a violation is suspected or to confirm the diagnosis, additional studies may be prescribed.

The most accurate results in this case are provided by transvaginal ultrasound. During the procedure, a special thin sensor is used, which is inserted into the vagina. A condom is first put on it. The sensor is very thin, pain and discomfort are excluded. It is located at a minimum distance from the uterus. It is completely safe and does not cause any threat of miscarriage or cause any discomfort.

Advantages of ultrasound in diagnosing pregnancy - to the maximum precise definition deadlines. You can set the gestation time to the nearest day. This also allows you to accurately calculate your due date. Studies at 10-12, 20-22, 30-36 weeks do not have such accuracy due to the fact that each child develops individually in the womb.

Ultrasound in early pregnancy

At 10-12 weeks it is necessary to evaluate:

• The condition of the umbilical cord and make sure that there are two arteries in it;
• Cervix - measure the length;
• Place of attachment of the chorion in the uterus;
• Fruit size.

At this stage, the gestational age is clarified and possible pathologies: Edwards syndrome, Down syndrome, Patau syndrome, abnormalities of the brain and other organs.

How is an ultrasound performed at 10-12 weeks?

The examination method is chosen by the treating gynecologist. Most often, the study is performed transabdominally - through the abdominal wall. The procedure algorithm is simple:

• The woman sits or lies down on the couch;
• A doctor or nurse applies a sound-conducting gel to the woman's abdomen;
• The doctor places the sensor on the abdomen and slowly moves it over the surface;
• The image is displayed on the monitor.

The procedure lasts a few minutes, after which the pregnant woman can immediately return to her usual activities. An ultrasound scan during pregnancy does not require any special preparation; it can be done at any time of the day.

For special indications, ultrasound is performed transvaginally. This is necessary when:

• Attachment of the chorion or placenta at a low level;
• The position of the fetus is difficult for measuring the collar area or other parts of the body;
• The need to assess the degree of isthmic-cervical insufficiency;
• Diagnosis of inflammation of the appendages or neoplasms in a pregnant woman.

Ultrasound at 21-22 weeks

The second ultrasound shows the size of the fetal body parts, its anatomy, internal organs. Allows you to again clarify the duration of pregnancy, identify developmental delays, and find pathologies of the placenta, uterus, cervix, and umbilical cord. The maturity of the placenta is determined premature aging, the amount of water is set. At this time, the sex of the child is most often determined.

The second ultrasound is performed only transabdominally - transvaginal examination is not prescribed until after birth. The procedure is similar to the first ultrasound.

When is the last time an ultrasound is performed during pregnancy?

An ultrasound scan at the third screening is done at 30-31 weeks. As in the second study, the third ultrasound evaluates the condition of the uterus, placenta, umbilical cord, waters and the fetus itself. In addition, it is necessary to determine the presentation of the embryo - the position inside the uterus. Normally it is cephalic, that is, the fetus lies head down, with the top of the head towards the exit. It is important to establish the position of the placenta, the length of the cervical canal, and check the quality of the placenta.

The course of the third study does not differ from the course of the previous ones. An ultrasound is performed only on the abdominal wall.

Ultrasound before birth

Some women have an ultrasound scan upon admission to the maternity hospital. This is necessary to assess the condition of the woman and fetus and plan childbirth. The position of the embryo, height and weight, the condition of the cervix (maturity and degree of dilatation), the child’s heart rate, and blood flow in the vessels of the mother and fetus are taken into account. The study is also carried out only transabdominally.

Which ultrasound is better during pregnancy - 3D or simple?

The difference between 3D ultrasound during pregnancy and a regular one is only in the resulting image. During a normal examination, it is understandable only to the doctor, but the patient, as a rule, has difficulty examining the picture. Three-dimensional ultrasound allows you to see a clear three-dimensional image in color. High contrast and clarity allow you to examine the embryo in detail even at the earliest stages. If desired, a woman can get the first photo of the child printed on a printer from the doctor.

These types of ultrasound do not differ in terms of the level of impact on the child or other parameters - both are harmless to the fetus and painless for the mother. For getting more For positive emotions, it is better to choose a 3D ultrasound, but if it is not possible, you should not be upset.