What is looked at by the ctg of the fetus. Problems with decoding the results. What are the norms for examining the fetus during pregnancy with the CTG method?

09.05.2019

What is CTG in pregnant women? Cardiotocography (CTG) is a method of functional study of the state of the fetus in the womb of a pregnant woman, which is based on sequential recording of the baby's heart rate and its changes in accordance with the contractile movements of the uterus, the impact of environmental factors and the activity of the baby himself.

This recording of the heartbeat is carried out for 15 minutes and can be carried out both in a calm state of a woman outside the labor process, and during labor and childbirth. This feature makes CTG a rather effective and useful method for resolving the issue of tactics of childbirth.

What does CTG show? First of all, this type of research is carried out in order to obtain information about fetal heart rate, the regularity of his cardiac activity, as well as active movements.

In addition, the information content of CTG is very important in relation to determining the frequency of contractions of smooth muscle cells of the uterus and the child's response to these contractions.

Cardiotocography is an effective research method to exclude or timely determination of pathological conditions of mother and child that threaten the course of pregnancy and for the future health of the newborn baby, such as intrauterine infection of the fetus, oligohydramnios, congenital abnormal development of the cardiovascular system, placental insufficiency and the threat of childbirth starting earlier than planned.

The main indications for CTG

A woman with Rh-negative blood, at risk of developing hemolytic disease of the newborn.
A history of premature labor, miscarriages and abortions.
Feelings of decreased fetal movements in the pregnant woman herself.
Complications during pregnancy (, multiple fetuses, polyhydramnios, oligohydramnios, fever or low-grade fever in a pregnant woman, incorrect presentation of the baby, post-term pregnancy).
Violations in a child that were previously found with (developmental delay, disturbances in the amniotic fluid, decreased activity, pathological changes in blood circulation in the placenta, too large or small size of the child, not corresponding to the month of pregnancy).
Endocrine and systemic diseases in a pregnant woman (the first and second types, diseases of the cardiovascular system,).

This method of examining the state of the child during the period of his intrauterine life is safe, since the sensor reproduces an ultrasound wave of weak strength, does not negatively affect the baby.

How long does CTG of the fetus take?

The use of cardiotocography can be started with approximately, but a high-quality and informative recording of the above parameters characterizing the state of the child in the womb is possible only with.

This is due to the development in the baby of periodically replacing cycles, when he is active or calm in a motor relation. The baby is most active from 9 to 14 o'clock in the afternoon, as well as from 19 to 24 o'clock in the evening.

How to prepare for CTG during pregnancy? CTG is contraindicated after a meal, since increased CTG can significantly affect the fetus, enhancing its movements and response to external environmental stimuli.

How is fetal CTG done during pregnancy

Cardiotocography is performed using specialized sensor, which has an ultrasonic effect and is based on the effect.

This device is tightly attached to the front of the pregnant woman's belly, where the baby's heart sounds are most clearly heard. Such an area is preliminarily determined without problems with an obstetric stethoscope.

The sensor, producing a signal in the form of an ultrasonic wave, directs it towards the baby's heart in the womb. The wave is reflected from the heart, which is perceived again by the same sensor as a result. The information received is converted to values fetal heart rate in one minute... The research results are reproduced by sound, light and graphic method on a tape.

If the pregnancy is normal, CTG is carried out no more than once a week. With a complicated course of pregnancy, but with good results from previous methods for examining the fetus, this procedure is performed with a pause of an average of 6 days.

If it has developed child hypoxia in the womb, CTG is indicated for daily use or every other day for constant dynamic monitoring of the child's condition and timely taking measures for emergency childbirth.

Deciphering the results of CTG of the fetus during pregnancy

Evaluation of the results of the performed analysis of cardiotocography is carried out a specialist in a number of indicators, which include the basal rhythm, variability, acceleration, deceleration and, finally, the activity of the baby's movements in the womb. All this is depicted at the end of the manipulation on paper in the form of graphs of various shapes.

How to decipher CTG? You yourself should not try to decipher your CTG, since you, not being a doctor, will be mistaken when deciphering fetal cardiotocography in calculating points according to the results obtained, which, of course, can harm the child.

Basal rhythm Is the average value of the fetal heart rate. Normally, the basal rhythm reaches from 110 to 160 heart beats per minute with the calmness of the baby and the pregnant woman. When the child moves, the frequency of contractions increases to values ranging from 140 to 190 beats.

All normal values of the basal rhythm indicate absence of a hypoxic state the baby's body. And an increase in frequency, as well as a decrease, are a clear sign of fetal hypoxia, which, first of all, is detrimental to its nervous system, although it is not yet fully developed.

Variability(in another way, amplitude) - the change in the value of the heart rate and its amplitude relative to the obtained values of the basal heart rate of the baby's heart.
Outside of pathology, the heart rate of a child in the womb should not be constantly the same and monotonous, which is well visualized by the continuous change of numerical values on the monitor during CTG. Normal changes in the corresponding parameters should be in the range from 5 to 25 beats per minute.

An increase in amplitude may indicate the same fetal hypoxia or, which is undoubtedly a pathology. Decreased amplitude values may be normal if at the time of CTG the baby is in a calm state. In order to "wake up" the baby, mom can just eat some sweetness.

Acceleration(increase) - an increase in the number of heart beats compared to the level of the basal heart rate. The amount of acceleration is expressed on the cardiotocogram in the form of teeth, normally it is at least 2-3 times within 15 minutes... It is permissible to increase the number of trainings up to 4 in half an hour. Their complete absence for the specified time period is pathological.

Deceleration(decrease) - decrease in heart rate values in comparison with the level of basal heart rate. The amount of deceleration is expressed already in the form of dips ("negative" teeth). Normally, such manifestations on the graph should not attend or be insignificant in depth, duration and occurrence.

The deterioration of the baby's condition in the womb can be confirmed by the occurrence of decelerations after 20 minutes of the study. Also a bad result is their repetition and different appearance throughout the entire graph. All this may indicate decompensated fetal stress.

Overall decryption norms of CTG results the fetus looks like this:

The basal rate is 120-159 per minute in a calm state.
Variability from 10 to 25 beats per minute.
2 or more accelerations within 10 minutes.
Lack of decelerations.

Pathological CTG as follows:

The basal rate is less than 90 and more than 180 per minute.
Variability less than 5 beats per minute.
Absence or small number of accelerations.
The presence of different types of decelerations.

Fisher's ten-point scale

The results of cardiotocography are assessed by specialists on a ten-point Fisher scale, which is based on assigning points from 0 to 2 to each of the above indicators. These points are summed up, and a general conclusion is made about the information content of CTG and the presence of pathological changes in the fetus. The so-called Fetal health indicator(PSP).

If sum of points CTG made from 1 to 5, then the condition of the baby in the womb is poor, he experiences hypoxia (lack of air).
What does it mean if the sum of KTG points was 6-7 ? The child shows initial signs of developing oxygen deprivation.
What does it mean if the sum of KTG points is from 8 to 10? This speaks of the norm and good condition of the baby.

With a PSP of 1-5 points, immediate childbirth is indicated, with a PSP of 6-7 points - repeated CTG, with a PSP of 8-10 points - continuation of periodic monitoring of the pregnant woman and the fetus using this research method.

How pregnancy can affect CTG indicators

If CTG is performed earlier than 29-32 weeks of pregnancy, it can become uninformative and meaningless, since it is by this period that the fetus develops a sleep and wakefulness regime, and earlier it manifests itself only as calmness in the mother's stomach.

Depending on the week, the indicators are approximately the same, but the smaller the week, the higher the variability (amplitude).

The fact that the doctor did not like the results of cardiotocography does not mean the final determination of the fetus of hypoxia and pathology in principle. There are cases when young doctors without sufficient work experience misinterpreted the information that the received schedule carries, although everything was completely normal for the baby and his mother.

Therefore, you should not rush and immediately panic when you get a bad result. But one should not relax either, since this may and in fact indicate a real pathology that requires immediate treatment and action on the part of medical workers.

Most likely, in case of results with alarming deviations from the norm, the doctor will ask you to travel to hospital in maternity hospital, where they will conduct regular CTG and will be able to quickly respond in a dangerous situation.

How contractions manifest on CTG

This research is required will indicate the presence of contractions, since normally the uterus should respond to the active motor activity of the baby with its spasms. In addition, the uterus has the ability to contract spontaneously. On CTG, in response to contractions, a decrease in the number of heartbeats of the child and deceleration will be seen, which is rare.

The second curve (hysterogram) reflects the increase in the force of contraction of the myometrium (the muscle layer of the uterus) during contractions. The higher it is, the stronger the contractions. Some women in labor do not feel the contractions, CTG helps to determine their strength and frequency.

What is the Fetal Reactivity Index

This indicator tells the specialist about the state of the fetus's nervous system reactivity to external influences, which, first of all, affects the state of the cardiovascular system.

The counting is done in a point system. and further interpreted:

0 points mean an absolute lack of reactivity in the baby.
1 point means severe disturbances in the reactivity of the organism.
2 points mean pronounced disorders of the baby's reactivity.
3 points mean a moderate degree of impairment in reactivity.
4 points mean the initial stage of the pathology of the child's reactivity.
5 points indicate normal fetal reactivity.

What is a non-stress test?

This type of research on the state of the baby in the womb is heart test according to the movements of the child.

A good result is a negative non-stress test (the presence of 2-3 increases in the number of heartbeats by about 15 beats per minute for 15-20 seconds). In the case of a positive or no result at all, it can be concluded that the baby is in a hypoxic state, which, in fact, may be a false phenomenon if at the time of the study the fetus was calm and asleep. In this case, the non-stress test is shown to be repeated.

Cardiotocography is one of the most accurate methods for determining the baby's hypoxia in the womb of a pregnant woman, which is very valuable for its timely diagnosis and taking measures to eliminate it. In the presence of hypoxia on CTG there are the following changes:

Reduction or complete deficiency of fetal heartbeats.
An increase in heart rate when the fetus moves or the uterus contracts involuntarily.

Erroneous assessment of CTG results

Errors in the interpretation of information obtained using cardiotocography are certainly possible. For example, in case of hypoxia, but despite the fact that the baby's tissues have already managed to adapt to it, CTG is not able to show this pathological condition. The same can happen if there is a sufficient amount of oxygen in the bloodstream, but the tissues cannot adequately accept and use it, which indicates actual fetal hypoxia.

The presence of errors obliges specialists to evaluate the results of CTG only in conjunction with the results of other studies carried out by a pregnant woman, and after that make a final diagnosis.

Video about fetal cardiotocography (CTG)

We invite you to watch a video about the CTG of the fetus. The obstetrician-gynecologist will tell you how and why this examination is carried out, how its results are assessed, what are the normal CTG indicators.

Any pregnant woman will sooner or later undergo CTG, some of the readers have already met with this study. That's why tell us about your impressions from cardiotocography, how you deciphered its results, and what gave you the passage of this painless manipulation. Do not forget to leave reviews, ask questions about CTG, the answers to which excite you the most or still remain unclear.

To assess the condition of the fetus, doctors prescribe various tests for pregnant women. The most common is ultrasound. In addition to ultrasound examination, women undergo CTG - cardiotocography. This method allows specialists to identify serious pathologies in unborn children and take the necessary measures in a timely manner. What is CTG and what is it prescribed for? What important information do doctors receive from this study?

Cardiotocography is the most acceptable way to assess the condition of a child who has not yet been born. During the study, a graphical registration of uterine activity and the frequency of fetal heart contractions is carried out. Experts evaluate the results obtained and draw appropriate conclusions.

The essence of cardiotocography

The study is carried out using a special device called a cardiotocograph. An ultrasonic sensor is designed to record heartbeats. Uterine activity is recorded by strain gauges.

All information is recorded on a cardiotocogram. It is a graph with two lines. The first curve is a tachogram. It is used to assess the work of the child's heart. The second curve on the graph is the histogram. It is used to assess the change in the force of contraction of the uterus.

CTG during pregnancy and during delivery

Cardiotocography is done during pregnancy. The strain gauge is installed in the area of the fundus of the uterus. It is not placed on the lateral surfaces of the abdomen. The ultrasonic transducer is then placed. Its location is determined depending on the presentation and maturity of the fetus.

For cephalic presentation and full-term pregnancy, the sensor is placed slightly below the navel. As a rule, only in this place is it possible to receive a stable audio signal. With breech presentation, the ultrasound sensor is placed closer to the bottom of the uterus, and in premature pregnancy, closer to the pubic joint.

Cardiotocography is also done during delivery. Heartbeats are recorded using a special electrode. It is inserted into the presenting part of the fetus. Uterine contractions are fixed with a catheter inserted into the organ cavity.

Indications for cardiotocography

The first study of women in position takes place at about the 32nd week of pregnancy. If the results are good, then repeated CTGs are prescribed 1 time in 7-10 days. There is no point in doing research more often.

If the period of bearing a child proceeds with complications, then cardiotocography is performed with any changes in the condition of a pregnant woman. Indications for frequent monitoring:

miscarriages and premature births in the past;
the woman has any chronic diseases;
gestosis (complication during pregnancy, which is manifested by an increase in blood pressure, edema, convulsions);
lack of water or polyhydramnios (decrease or increase in the amount of amniotic fluid);
developmental defects in a child;
multiple pregnancy.

When labor begins, doctors conduct an initial cardiotocographic study. If its results are favorable, then repeated CTG in the first period is done every 3 hours. In the second stage of labor, constant monitoring is carried out.

If, in the course of the initial study, made at the beginning of labor, specialists receive unfavorable data, then continuous monitoring begins immediately. Monitoring is carried out before a decision is made to conduct a caesarean section or to refuse it.

Sensors of the cardiotocography apparatus on the belly of a pregnant woman

Basic rules for conducting CTG

The posture of pregnant women at the time of the study is an important factor influencing the results. Cardiotocography is recommended with the patient on the left side. A sitting position is also allowed. Lying on your back is not worth carrying out cardiotocography. The results will be unreliable due to the compression of the blood vessels by the uterus.

Another rule of CTG is the use of a special acoustic gel. It is applied to a sensor that records the work of the baby's heart. Sometimes the gel is not treated with the sensor, but the belly of the pregnant woman. This is not considered a bug. But the strain gauge must be left dry. The gel is also not applied to the place of its fixation.

The duration of cardiotocography plays an important role. Short-term recordings are undesirable, because in such cases, there is a high probability of obtaining false results. The duration of the cardiotocography should be about 20 minutes. If the study shows pathological or disturbing rhythms, then it is performed within 40 minutes.

During childbirth, the duration of cardiotocography should be at least 20 minutes. If suspicious signs are found, then the study is not stopped. The recording continues until the moment when a decision is made on the further tactics of conducting childbirth.

Assessment of cardiac activity

During the study of the cardiotocogram, all parameters that characterize the work of the fetal heart are considered. Subject to assessment:

deceleration and acceleration;
basal rhythm;
variability of the basal rhythm.

Deceleration and acceleration

When evaluating the cardiotocogram, manifestations of irregularity of the heart are necessarily analyzed. They are called decelerations and accelerations. Deceleration is a slowing down of the heart by 15 beats per minute for 15 or more seconds. Acceleration is called an increase in heart rate.

Normally, on the cardiotocogram, manifestations of a slowdown in the work of the heart should be absent. The presence of sporadic (unpredictable) peak-like deceleration after acceleration with a depth of up to 30 beats per minute and a duration of no more than 20 seconds is allowed. Accelerations in response to fetal movements should be at least 4 for 20 minutes.

Basal rhythm

This term means the average heart rate for a specific time period without taking into account decelerations (decreases in heart rate) and accelerations (increases in heart rate). An indicator equal to 120-160 beats per minute is considered normal.

Sometimes deviations come to light:

Decreased basal rhythm. An average heart rate of 100-120 beats per minute is a sign of moderate bradycardia. A very small basal rhythm (less than 100 beats per minute) indicates the presence of severe bradycardia.
Increased basal rhythm. If the indicator is 160-180 beats per minute, then experts talk about mild tachycardia. If the basal rhythm is higher than 180 beats per minute, then this indicates a pronounced tachycardia.

Basal rhythm variability

This indicator, assessed by cardiotocography, consists of several components. However, experts pay attention mainly to the amplitude and frequency of oscillations (deviations of heart rate from the average basal level).

The amplitude of a particular oscillation is the distance between the peaks of the upper and lower wave. This indicator is assessed using horizontal lines. They are applied to registration paper every 5 beats per minute. For example, if the peaks of the upper and lower oscillation teeth are located on opposite adjacent lines, then the amplitude is 5 beats per minute. Normally, the oscillation amplitude is 6-25 beats.

Oscillation frequency - the number of similar basal frequency oscillations that occur in 1 minute. The indicator is calculated by the number of heart rate peaks. The frequency of oscillations is normally more than 6 cycles per minute.

CTG results: possible pathologies

If most of the indicators are outside the physiological norm, then doctors diagnose intrauterine fetal hypoxia, that is, oxygen starvation. This condition is quite dangerous. Due to the lack of a vital element, the metabolism in the child's body is disrupted. If a lack of oxygen is detected, doctors record CTG daily.

Hypoxia can be severe. For a cardiotocogram reflecting this pathology, the following indicators are characteristic:

basal rhythm more than 180 or less than 100 beats per minute;
no acceleration for 30 minutes;
the presence of pronounced variable decelerations;
the amplitude of the oscillations is less than 3 beats;
the number of oscillations is less than 3 cycles per minute.

Severe hypoxia indicates that intrauterine fetal death may occur suddenly. When diagnosing this pathology, doctors perform an immediate delivery. Timely detection of hypoxia can save a child's life.

Sometimes, with cardiotocography, only bradycardia or tachycardia is detected. No other changes are detected. In such cases, this change in cardiac activity does not indicate the presence of hypoxia. The unborn child may have some kind of congenital heart disease.

Is research dangerous?

Is CTG harmful is a question that arises in almost all pregnant women. In this regard, it should be noted that there are no contraindications to CTG. The study is assigned to absolutely all pregnant women and women in labor. It does not pose a serious danger to the expectant mother and child. In addition, cardiotocography is a painless procedure.

Although the study is safe, complications sometimes arise. They appear only after internal cardiotocography performed when the membranes are ruptured. However, negative consequences are extremely rare. The fact is that the specialists leading the research follow the rules of asepsis and antiseptics.

Cardiotocography is a highly informative diagnostic method. If signs of well-being come to light, then nothing threatens the child in the near future. The results remain valid for 7-10 days. If the cardiotocogram does not indicate the well-being of the fetus, then the child may have hypoxia. In such cases, any outcome options are possible that cannot be predicted using CTG. It all depends on the doctor who decides on the further tactics of pregnancy management.

Cardiotocography is an important study of a still very small human heart and helps to identify pathologies at an early stage, to begin to correct problems. What does the CTG of the fetus show, how to decipher the analyzes and how to determine if the baby's condition is normal?

What is CTG in pregnant women

CTG during pregnancy is a method for assessing uterine contractions and the baby's heartbeat, which develops even in utero. Research is important in that it allows you to identify deviations from the norm at an early stage. Doctors, using an apparatus for listening to the fetal heartbeat, define this procedure as mandatory for the expectant mother as ultrasound and Doppler.

A check with a cardiotocograph is prescribed, starting from the 30th week, before this period, only women who have indications for CTG during pregnancy are examined. The procedure confirms whether the baby is healthy, whether there are dangerous pathologies for a pregnant mother or baby. If a specialist has identified any anomalies, then the doctor from the antenatal clinic should adjust the process of pregnancy, and in some cases, therapeutic measures are taken. Such diseases include:

hypoxia in a child;
lack of water or polyhydramnios;
functional disorders in the placenta;
fetal tachycardia;
disorders of the cardiovascular system.

In what cases is fetal cardiotocography indicated?

Heartbeat and uterine contractions on CTG are checked in such cases:

If the condition of the baby and mother is normal, then CTG is done once with a normal pregnancy. If the recording recorded pathological changes, an overwrite is assigned. The procedure is carried out from the 30th week of pregnancy.
If past pregnancies were unfavorable (death of a child in utero, genetic and chromosomal abnormalities).
Mom's feelings that something is wrong with the child. Every mother already knows how the baby behaves in the womb. If there are changes in the regime, the activity of the child, then the pregnant woman should pay attention to this.
With the course of acute diseases (flu, tonsillitis, ARVI), chronic infections in a pregnant woman and treatment on an outpatient basis or in a hospital.
With gestosis in a pregnant woman.
If a woman is subject to bad habits: during pregnancy, she smokes, takes alcohol or drugs.
In case the pregnant woman suffers from chronic diseases of internal organs.
If the pregnancy is prolonged.

How long does CTG of the fetus take?

If the pregnancy is proceeding normally, there are no complications, then CTG is recommended to take place in the third trimester 1-2 times. If during the first studies some pathological changes are found, then an additional research procedure is prescribed. A checkup procedure is carried out during childbirth in order to comprehensively assess the general condition of the baby. During a contraction, a CTG is recorded, according to which the condition of the child is assessed, and decisions are made on further delivery. This is especially true for babies with an umbilical cord entanglement.

Why do CTG for pregnant women

Using only this research method, one cannot be sure of the reliability of the diagnosis. The condition of the baby inside the mother can change due to the woman taking medication, depending on the food intake, mood, reactions to external stimuli. CTG helps to identify such pathologies during pregnancy:

Umbilical cord entanglement. Such a condition is dangerous by a violation of the supply of oxygen from mother to child. Blood flow not restored in time can lead to a serious condition.
Irregularity of the fetal heartbeat. This is a signal that there are heart abnormalities.
Hypoxia. During the study, small signs of pathology will be noticeable.

The procedure is carried out quickly, which gives a real chance to assess the condition of the child even during childbirth, to resolve labor activity as correctly as possible. If the mother has pathologies that affect the fetus, then the woman is sent to the hospital, monitored and recorded daily. If abnormalities are detected, the expectant mother is examined for ultrasound and Doppler ultrasound is performed. If the diagnosis has been confirmed, then treatment is prescribed, in which CTG is done every day 1-2 times in order to assess the effectiveness of treatment, to monitor the condition of the fetus.

How is CTG performed for pregnant women and during childbirth

The procedure is safe, but you need to prepare. A woman should sleep well, not experience nervous breakdowns, stress, be completely calm. For the study to give the most accurate result, the child needs to be active. To do this, the mother needs to eat something sweet before the procedure, preferably a chocolate bar. The woman takes a lying or reclining position, is comfortable. A pressure transducer (strain gauge) and an ultrasonic transducer are attached to the abdomen. The first controls the contractions of the uterus, the second controls the fetal heartbeat. The recording lasts 30-60 minutes.

Decoding CTG of the fetus

The method of explaining the Fischer results is the most used and takes into account the parameters:

The average heart rate is from 119 to 159 beats in 60 seconds.
Fluctuations in the frequency of heart contractions - the norm is from 5 to 25 beats.
The frequency of changes is normal with 6-10 teeth on the curve.
Increased heart rate of the child (acceleration) - for 10 minutes at least 2 times.
Deceleration is the reverse process to the previous one, in the absence of pathology it should not be.

Each feature is rated on a scale from 0 to 2. How many points should there be for each? The indicator of the norm - 2 points, a slight deviation up or down - 1 point, critical inconsistencies - 0 points. Explanation of the survey looks like this:

4 or less points - the index shows an acute condition, the doctor must prescribe treatment, observe the patient regularly;
5-7 points - an indicator of oxygen starvation;
8-10 - the child is fine.

Video: what is fetal CTG during pregnancy

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Clinics performing CTG

What does KTG ( cardiotocography)?

CTG ( cardiotocography) - This is a research method that allows you to assess the condition of the fetus in the womb during pregnancy. Also, during the study, the specialist can assess the contractile activity of the pregnant woman's uterus. This is a simple, fast and safe procedure that can help to identify various disorders of the fetus that pose a threat to its further development. Timely identification of such violations will allow the doctor to take the necessary measures to correct or eliminate them, thereby preventing further damage to the fetus or the development of complications during pregnancy and / or childbirth.

The essence of the method is that with the help of special sensors, the fetal heart rate is recorded, as well as the frequency and strength of uterine contractions ( in which the fetus is). The registered changes are recorded on special paper, and their study allows the doctor to assess the condition of the fetus.

In order to understand how the method described above works and how, on its basis, it is possible to assess the state of the child in the womb, certain knowledge about the course and development of pregnancy is required.

Under normal conditions, the human heart begins to contract in the womb ( by about the end of 1 month of intrauterine development). However, in the beginning, the heartbeats are uncoordinated and unrelated to the rest of the body. As the central nervous system develops ( CNS), endocrine, circulatory and other systems, they ( system data) begin to have a certain effect on the heartbeat. So, for example, activation of certain parts of the central nervous system can cause an increase or decrease in the heart rate ( Heart rate). Various hormones ( secreted in the body of the fetus or mother), as well as various pathological situations that may occur during pregnancy and childbirth.

As a result of many studies, scientists have found that normal ( with a normally developing pregnancy) the heart of the heart beats at a strictly defined frequency ( an average of 110 to 150 beats per minute). They also noted that the fetal heart rate can change depending on various external influences, as well as in the presence of certain pathological conditions and / or diseases. Consequently, certain changes in the heart rhythm allow the specialist to determine the condition of the fetus, as well as to suspect the presence of certain pathologies and take measures to eliminate them.

The principle of operation of the CTG apparatus ( what the sensor shows)?

As mentioned earlier, during the CTG procedure, fetal heart contractions are assessed, as well as uterine contractions ( her muscle layer) and fetal movements. To register these processes, two different sensors are used, the principles of which are also different.

During CTG, the following is recorded:

Fetal heart rate. For this, an ultrasonic device with a Doppler function is used. The principle of operation of this device is as follows. Initially, the device emits ultrasonic waves, which are directed deep into the human body. Colliding with various tissues, these waves are partially reflected from them and returned back to the sensor, which registers them. If you direct such a device to a blood vessel through which blood flows ( including the heart of the fetus, which is in the womb), ultrasonic waves will be reflected from the blood cells, which are in constant motion. Moreover, thanks to the Doppler effect, it will be possible to determine in which direction the blood is moving ( towards or away from the sensor). Thus, evaluating the nature of blood flow through the fetal heart, the apparatus can determine its heart rate with high accuracy.
Contractions of the uterus. For this, a so-called strain gauge sensor is used, which registers the slightest changes in the volume of a woman's abdomen. Outwardly, it resembles a belt that wraps around the abdomen and tightens slightly. During the next contraction of the uterus, the size of its upper part ( bottom) increase slightly. As a result, the sensitive element of the strain gauge will stretch, which will allow registering the uterine contraction.
Movement ( stirring) fetus. They are also recorded by a strain gauge sensor.

It should be noted that during CTG, both sensors are installed simultaneously ( a strain gauge sensor in the upper abdomen, and an ultrasound sensor in the area of the intended location of the fetal heart), also simultaneously registering fetal heart rate and uterine contractions. The data obtained is recorded on special paper in the form of two curved lines, which are located one above the other. This allows you to assess the fetal heart rate during uterine contractions, during active movements and at rest, which is also important for making a correct diagnosis.

What's better ( more informative) - CTG, ultrasound or Doppler?

Each of these methods is used to identify various pathological conditions in specific situations during pregnancy, so it is impossible to say unequivocally which one is better.

To assess the condition of the fetus in the womb, use:

CTG. It allows you to assess the fetal heart rate and the contractile activity of the uterus, which allows you to identify various pathological conditions in late pregnancy ( in the third trimester).
Ultrasound ( ultrasound procedure). At different stages of pregnancy, it is used for different purposes. So, for example, in the early stages, ultrasound can be used to confirm the presence of pregnancy, to detect an ectopic pregnancy ( when the embryo begins to develop outside the uterine cavity, which poses a danger to the woman's life), as well as to identify various developmental anomalies. At a later date, ultrasound can also detect intrauterine developmental anomalies.
Doppler ultrasound. Doppler ultrasound allows you to assess blood flow from the placenta to the fetus, in violation of which there may be intrauterine growth retardation or even death of the child. At the same time, this study allows us to identify some other anomalies ( for example, twisting the umbilical cord around the baby's neck).

What is the difference between CTG and ECG?

Cardiotocography and ECG ( electrocardiography) Are two completely different procedures used to register completely different data.

The essence and principle of cardiotocography were described earlier ( with the help of ultrasound, the heart contractions of the fetus are recorded, and with the help of the strain gauge - the uterine contractions and movements of the fetus). Unlike CTG, ECG records the electrical activity of the human heart. The fact is that the activity of the heart muscle is regulated by electrical impulses. These impulses arise in strictly defined areas of the heart and propagate in a strictly defined sequence, which ensures the regularity and efficiency of heart contractions. Pulse data recording on paper ( electrocardiogram) allows you to obtain characteristic curved lines. With various diseases of the heart, blood vessels or lungs, the electrical activity of the heart will change, which will be reflected in the electrocardiogram.

To perform an ECG, on the human body ( on his arms, legs and chest) it is necessary to install special electrodes, which will record the electrical activity of the heart. Therefore, this procedure can be performed for a newborn, child or adult, but not for a fetus in the womb.

When and why do you need a CTG study during pregnancy ( testimony)?

Cardiotocography allows you to assess the state of the child's heart and its ability to adapt to changing environmental conditions, which can help in identifying various pathological conditions.

CTG can be assigned:

During pregnancy- to assess the condition of the fetus and identify developmental pathologies.
Before childbirth- to assess the child's readiness for birth.
During childbirth- to assess and constantly monitor the condition of the fetus, as well as to timely identify various pathological conditions that may develop when the child passes through the birth canal of the mother.

Is it necessary to do CTG during pregnancy and can you refuse it?

Today CTG is not an obligatory procedure, although most obstetricians and gynecologists recommend performing it during pregnancy for all women. If the pregnancy is proceeding normally, the woman may refuse to conduct this study. At the same time, if any risk factors are identified that may pose a threat to the development or life of the fetus, the doctor may insist on performing cardiotocography at various stages of pregnancy or childbirth.

Indications for CTG may be:

Diseases of the mother during pregnancy- severe infectious diseases, poisoning, increased thaw temperature, high blood pressure ( including preeclampsia, characterized by a pronounced increase in blood pressure and a tendency to develop seizures), lack of water and so on.
Fetal motor activity disorders- for example, if for a long time the mother does not feel the movements or pushes of the fetus in the abdomen.
Abdominal pain, the cause of which has not been established.
Injuries during pregnancy- especially abdominal injuries that could harm the fetus.
Complications from previous pregnancies- spontaneous abortion, fetal anomalies, post-term pregnancy, premature birth.
Problems during a previous birth- entanglement of the umbilical cord around the neck of the fetus, abnormal presentation of the fetus, premature placental abruption, the presence of scars on the uterus ( after the transferred operations) etc.

When ( what week of pregnancy) make the first CTG?

For the first time, this study is recommended for women at 32 weeks of gestation. At an earlier date, it is also possible to register the fetal heart rate, but this will not give any significant information about its condition. The fact is that under normal conditions, the heart of the embryo is formed and begins to contract by the end of 1 month of intrauterine development. However, at the same time, it has nothing to do with the nervous system of the body, as a result of which it does not reflect the general condition of the baby.

By 29 - 30 weeks of intrauterine development, the heart "connects" with the so-called vegetative ( autonomous) the nervous system, which will regulate its activity throughout the rest of his life. This system is responsible for the adaptation of the body to changing environmental conditions, and it is this system that ensures changes in heart rate when the state of the fetus changes. So, for example, if a child begins to move in the womb, the need for energy will increase significantly, as a result of which, under the influence of the autonomic nervous system, the heart rate will also increase. Also, changes in heart rate can be observed in various pathological conditions. However, at first, these changes may be incomplete and inaccurate, since the activity of the heart is not yet fully regulated by the nervous system. The final development of this regulation is observed only by 32 weeks. It is from this period that any changes in the state of the fetus will affect its heart rate, which can be used for diagnostic purposes.

How often is CTG done to pregnant women and can it be done every day?

The frequency with which CTG is performed depends on the course of pregnancy, as well as on the results of previous studies.

If the pregnancy proceeds without complications ( the woman did not have infectious diseases, injuries or other pathologies), it is enough to perform the procedure at 32 - 33 weeks, as well as before childbirth ( at 37 - 38 weeks). This is done more for a preventive purpose ( to confirm that the pregnancy is proceeding normally and the development of the fetus is not at risk).

At the same time, in the presence of one or more risk factors ( listed above), as well as when violations are detected during the first procedure ( performed at 32 weeks of gestation) CTG may be prescribed more often ( weekly, several times a week, or even daily). The need for such frequent research is due to the fact that in the presence of certain diseases, damage to the fetus may develop, posing a danger to its further development or even to life. In this case, doctors will need to immediately make a decision on further treatment tactics or on urgent delivery ( through the vaginal birth canal or by caesarean section). Delay in this can lead to the most dire consequences.

What will CTG show during twin pregnancy?

With multiple pregnancies ( when not one, but 2 or more fetuses develop in the uterus) it is also possible to perform cardiotocography, however, certain difficulties associated with the research technique may arise.

As stated earlier, during the normal procedure, 2 sensors are used. One of them ( strain gauge) is fixed around the mother's abdomen and records the contractions of the uterus, while the other ( with ultrasound doppler function) is installed in the area of the proposed location of the fetal heart and assesses its functions. To evaluate uterine contractions in multiple pregnancies, one strain gauge is also sufficient. At the same time, a separate transducer with an ultrasound Doppler function must be used to assess the heartbeat of each fetus, each of which must be installed in the area of the fetal heart. In this case, the heart rate of both fetuses should be recorded simultaneously and compared with the uterine contractions, which will allow the doctor to obtain the most accurate data.

Why is CTG analysis done in the maternity hospital ( in childbirth)?

During birth through the vaginal birth canal, the fetus experiences significant stress. In this case, various pathological conditions can develop that threaten his life ( for example, when the umbilical cord is entwined around the neck and during prolonged labor, oxygen delivery to the fetus can be disrupted, which can cause damage to its central nervous system or even death). With the development of these complications, characteristic changes in the frequency and rhythm of heart contractions will be noted, which can be detected using CTG.

Usually, the procedure is performed at the onset of labor ( at the time a woman enters the hospital). If no abnormalities are detected, and childbirth is proceeding normally, the cardiotocography may not be repeated. If during childbirth there are any complications or deviations from the norm, the study can be performed as many times as necessary. If severe violations of the fetal heart rate are detected, the doctor may decide on further tactics of labor management ( that is, to continue labor through the vaginal birth canal or to resort to urgent surgery in order to save the life of the mother and / or fetus).

Is CTG of the brain done?

CTG of the brain is not done, since such a procedure does not exist. As mentioned earlier, during cardiotocography, the doctor examines the heart rate ( Heart rate) of the fetus, as well as the contractile activity of the uterus of a pregnant woman. Naturally, if the fetus has any serious damage to the central nervous system, this may affect the heart rate and rhythm. At the same time, it is impossible to directly assess the functions of the fetal brain using this study.

Is CTG done to a newborn?

Cardiotocography for a newborn is not done, since this procedure is intended solely for examining the condition of the fetus in the womb. After the birth of a baby, a number of other diagnostic methods are used to assess his condition.

You can assess the condition of the child after birth using:

ECG ( electrocardiography) - allows you to identify violations of the frequency and rhythm of heart contractions.
Pulse Oximetry- allows you to determine if there is enough oxygen in the child's blood, as well as to assess his heart rate.
Ultrasound ( ultrasound examination) - allows you to assess the functions of the heart and other internal organs.
Ultrasound doppler- allows you to assess the function of the heart and the patency of blood vessels.

How to properly prepare before CTG?

In order for the study to be as informative as possible, it is important not only to correctly perform the procedure itself, but also to properly prepare for it.

Cardiotocography is done on an empty stomach or not ( is it possible to eat before CTG)?

Food intake has practically no effect on the results of the study. This is due to the fact that under normal conditions ( with proper nutrition of the mother) the child receives all the nutrients necessary for his normal development.
If the mother does not eat in the morning before the procedure, the supply of nutrients in her body will be sufficient to supply them to the fetus for several hours. If the mother eats right before the test, this will also not affect the heart rate in any way ( heart rate) fetus.

At the same time, it is worth noting that some products may affect ( stimulate or depress) on the central nervous system and cardiovascular system of the mother and / or fetus, thereby causing certain changes in CTG. It is better to exclude such foods from the diet at least 48 hours before the scheduled study in order to avoid inaccuracies and errors during the evaluation of the results.

caffeinated drinks ( Tea coffee);
black chocolate ( more than 100 grams);
alcoholic drinks;
energy drinks;
protein food ( a lot).

However, it is worth noting that many doctors recommend that women eat something sweet ( for example, a few sweets or a cake, a piece of cake, and so on). It is believed that the intake of sugar ( glucose) into the blood stimulates the baby's motor activity, thereby making the study more informative.

Can I drink coffee before CTG?

Drinking coffee before cardiotocography is not recommended, as it may affect the quality and results of the study.

The fact is that caffeine, which is part of coffee beans, is a stimulant of the central nervous system ( central nervous system). When it enters the human body, it increases the respiratory rate, as well as the heart rate ( heart rate) and blood pressure. With an initially high blood pressure in a pregnant woman ( including against the background of preeclampsia) this can cause it to rise even more or even develop seizures. This can provoke a violation of oxygen delivery to the fetus, which will affect CTG.

At the same time, it is worth noting that even with normal pressure and the absence of preeclampsia, some of the caffeine can cross the placenta into the fetal bloodstream, causing the same changes in it. At the same time, a pronounced increase in the baby's heart rate above the norm will be recorded on the cardiotocogram, which can mislead the doctor.

Do I need to wake up the baby in the stomach before CTG?

It is not recommended to wake up the baby before the procedure with the help of external influences. For this purpose, one should not press on the stomach, run, jump, squat or perform other similar manipulations, since this not only will not give a positive result, but can also harm the developing fetus.

Under normal conditions, from about 28 to 30 weeks of intrauterine development, the child begins to clearly define cycles of activity ( "Wakefulness") and rest ( "Sleep"). At the same time, during sleep, he is relatively motionless, while while awake, he can roll over, "kick" with his arms or legs and perform other similar movements. When performing CTG, it is important to register the moment the child is awake, since it is during active movements that characteristic changes in heart rate will be noted, which are necessary for a correct assessment of the study. If the child is asleep, the study may be uninformative or register the "inactivity" of the fetus.

Considering this fact, as well as wanting the study to be informative and show "normal" results, many women decide to "wake up" the child immediately before the procedure, resorting to various external influences ( up to pressure on the abdomen). However, such actions can not only distort the research results, but also harm the fetus.

The fact is that under normal conditions, the sleep cycle in the fetus is no more than 50 minutes ( usually about 30-40 minutes). In other words, if a child is developing normally, at most every 40-50 minutes he should wake up on his own and start moving, which will be reflected in his heart rate. Therefore, if during the onset of CTG the baby is sleeping ( that is, does not move), it is enough to wait for a while, after which he will wake up and begin to move on his own. If the child does not wake up for an hour or more, it is possible that he has any developmental disorders. In this case, the doctor may increase the duration of the procedure or prescribe other diagnostic measures in order to clarify the diagnosis. At the same time, in the near future, the woman will most likely be prescribed a second CTG.

If, before the start of the study, the woman "wakes up" the child with an influence from the outside, he, of course, will move and CTG will show "good" results. However, if at the same time the fetus had any abnormalities or abnormalities, they may go unnoticed by the doctor and continue to harm the child in the future.

Do I need to take a blood test for CTG?

For cardiotocography, there is no need for any tests, including a general blood test. Also, the CTG procedure is carried out regardless of laboratory data, and the results of the mother's tests do not in any way affect the results of cardiotocography.

At the same time, it is worth noting that if during the study any abnormalities in the condition of the fetus are revealed, the woman may be assigned a number of additional studies and analyzes ( including blood tests) in order to identify the cause of the violation.

With a "suspicious" CTG, a woman can be prescribed:

General blood analysis- to identify anemia ( anemia) or infection.
Blood chemistry- to assess the function of the liver, kidneys, pancreas and other internal organs.
Hormone tests- to assess the function of the thyroid gland, adrenal glands and other glands.
Determination of blood sugar- to detect diabetes mellitus.
Analysis of the blood coagulation system- with an increase in the activity of this system in the blood of a woman, blood clots can form ( blood clots), which can disrupt the blood supply to various organs, including the placenta, which feeds the fetus and delivers oxygen to it.

What do you need to take with you to the CTG?

When going to this study, a woman needs to take only a towel with her, which she will have to lay on the couch, on which she will be during the procedure. You can also put a few dry wipes in your purse. They can be useful for wiping your stomach after the end of the study. The fact is that before applying the ultrasonic sensor to the skin, a gel is applied to it. This is necessary in order to prevent the reflection of ultrasonic beams at the border of air and skin. If this is not done, ultrasound beams will not be able to penetrate the tissues of the body to a sufficient depth and register the fetal heartbeats, as a result of which the study will be uninformative.

After the end of the procedure, the woman will need to wipe the gel off her stomach, as it can wet or stain clothes. Usually, in the office where CTG is performed, there should be napkins or a towel with which patients wipe the gel. However, if the doctor does not have napkins, it is better for the woman to have them with her.

You do not need to take any other devices or things with you for research.

Is it possible to use a telephone with CTG?

It is not prohibited to use a mobile phone, smartphone or tablet during the procedure. During the study, ultrasonic waves and a special strain gauge are used, on which mobile communication has practically no effect. That is why it will not create any hindrances to research.

At the same time, it should be noted that during the research it is recommended to refrain from lengthy telephone conversations ( including business calls), especially if they are accompanied by strong emotional experiences. This is due to the fact that emotional stress can cause an increase in pressure in the mother and activation of her nervous system, which can adversely affect the condition of the fetus. At the same time, he may also have an increase in heart rate, increased physical activity, and so on.

It is best to just listen to music or watch some kind of "neutral" video during your research, which will also not cause strong emotional distress.

How is the CTG procedure carried out?

Cardiotocography can be done at any gynecological clinic, maternity hospital or antenatal clinic. All that is required for this is an apparatus and a specialist who can read and correctly interpret the results of the study.

Which doctor does CTG?

The CTG procedure itself can be carried out even by a properly trained and prepared midwife ( sign up) ... At the same time, only a specialist, that is, a doctor, can correctly assess the results of the study, compare them with the symptoms of the mother, make the correct diagnosis and prescribe the necessary treatment. obstetrician-gynecologist ( sign up) ... This specialist is engaged in the diagnosis and treatment of diseases of the female reproductive system, pathologies of pregnancy and childbirth, and also knows the peculiarities of fetal development in the prenatal period. Only he can correctly assess the data obtained during CTG.

Do you need to sit or lie on your back during CTG?

During the study, it is best for a woman to be in a semi-recumbent position, with a raised ( by about 30 degrees) with the head end of the bed and slightly turning to the left side. In this case, you can put a small roller or a towel folded several times under the right side. This position is comfortable enough for the woman to remain stationary throughout the study ( which can last up to an hour or even more).

It is imperative that the woman does not lie on her back or ( which is more dangerous) on the right side ( especially in late pregnancy). The fact is that to the right of the spine there is a large blood vessel - the inferior vena cava, which collects blood from the entire lower part of the body and delivers it to the heart. If a woman lies flat on her back or bends over on her right side, a large fetus can easily transmit the inferior vena cava, resulting in impaired blood return from tissues to the heart. This can cause a drop in blood pressure and an irregular heartbeat in a woman, as a result of which she may begin to complain of nausea, dizziness, and darkening of the eyes. In extremely severe cases, she may lose consciousness ( due to a violation of the flow of blood to the brain).

It is worth noting that to the left of the spine there is also a large blood vessel - the abdominal aorta, through which blood from the heart flows to tissues and organs. When the woman is turned on her left side, the fetus can also put pressure on the aorta, but the blood pressure in it is so great that this will not cause any serious disturbances.

It is also important to remember that the head end of the bed on which the patient lies should be slightly raised throughout the entire examination. If this is not done ( that is, if a woman lies strictly horizontally), a large uterus and fetus can squeeze the lungs of a woman, thereby disrupting normal breathing. At the same time, after a few minutes, a woman may begin to complain of a feeling of lack of air, a feeling of heat, a rush of blood to the head, and so on. In this case, the woman should be immediately seated on a couch and allowed to breathe pure oxygen for 1 to 3 minutes ( if available).

It is worth noting that in some clinics, while performing CTG, a woman does not lie, but sits in a chair. This does not in any way affect the results of the study, and also prevents the development of the previously described complications ( the risk of which increases with multiple pregnancies, severe obesity in the mother, and so on). Also, the procedure can be done in a sitting or reclining position during childbirth, when a woman cannot lie on her left side.

How does CTG recording take place?

Before starting to record a cardiotocogram, the doctor must correctly install the sensors on the woman's body.

CTG includes:

Listening to fetal heartbeats. First, the doctor uses a stethoscope ( a special tube, one part of which the doctor inserts into his ears, and the other is applied to the mother's belly) determines the point at which the fetal heartbeat is heard best.
Installation of an ultrasonic transducer with Doppler function. This sensor is installed at the point of the best listening to the fetal heart rate and is fixed to the mother's abdomen.
Installation of a strain gauge sensor. This sensor is installed in the area of the uterine fundus ( that is, in the upper abdomen of a woman), where uterine contractions are best defined.

In some cases, a woman can be given a special device with a button in her hand, which she will have to press at the moment when she feels the movement of the fetus. At the same time, other devices register the movement data automatically.

After the end of all preparations, recording and registration of CTG begins. The received data is recorded on special paper, which is pulled out of the machine at a very slow speed. At the same time, you can see 2 curved lines on it. The upper line characterizes the fetal heart rate, and the lower ( tocogram) - contractile activity of the uterus. After a certain time, characteristic curves are formed on this paper, which the doctor examines when assessing the condition of the fetus.

How long does CTG take?

The duration of the procedure is on average 30 - 40 minutes. At the same time, in some cases, the study may end in 10-15 minutes, or vice versa, last more than an hour.

The purpose of cardiotocography is to record the heart rate ( Heart rate) of the fetus, as well as a change in its heart rate depending on the contractile activity of the uterus and depending on the movements it performs. The fetus moves intensively only during the wakefulness phase, and during sleep it is relatively motionless, therefore, it will not be possible to register a "normal" CTG.

Under normal conditions, the child's sleep cycle lasts about 30-40 minutes, as a result of which, during the half-hour study, he will have to wake up for at least a few minutes and begin to move. If at the same time characteristic changes are recorded on the cardiotocogram, the study can no longer be continued. Also, the study can be completed earlier if, immediately after the start of the study, the child moves actively enough. At the same time, if the child is inactive or asleep during the beginning of the procedure, its duration can be up to 60 minutes or more.

What does a fetal monitor with CTG analysis show?

A fetal monitor is a CTG examination apparatus that is equipped with a display ( screen). This screen displays in real time the results of cardiotocography, which, if necessary, can also be printed on paper. Everything else ( with regard to the principle of work, research technique and preparation for the procedure) a fetal monitor is no different from a conventional CTG.

It is worth noting that fetal monitors can be equipped with one or several Doppler ultrasound transducers. This means that they can be used to assess the condition of one or several fetuses at once ( with multiple pregnancies).

What do the sounds during CTG say?

During the study, the data recorded by the ultrasonic sensor can be reproduced not only on paper, but also in the form of characteristic sounds ( if your machine is equipped with a speaker). The nature of the sounds reflects the heart rate of the fetus and can also change depending on changes in heart rate. This helps the doctor to better navigate the data during the procedure, to adjust the sensors more correctly and to more accurately interpret the results obtained.

Why might CTG fail?

It should be noted that in a certain percentage of cases, the study may turn out to be uninformative. There can be many reasons for this.

The reason that CTG did not work out may be:

Incorrect sensor installation. Before installing the ultrasonic sensor ( fetal heart rate), the doctor should use a stethoscope to determine where the heartbeat is heard best. If the sensor is installed incorrectly ( not at the best listening point for the fetal heartbeat), the data it records may be inaccurate or may not be recorded at all.
Lack of fetal movement. During intrauterine development, the fetus spends most of its time asleep, remaining in a relatively immobile state. At the same time, the fetus may have a longer sleep, especially at an earlier date. As a result of this, his movements and active movements may be absent for an hour or even more. If during the registration of CTG the fetus does not actively move, it will not be possible to correctly record the cardiotocogram. In this case, the study can be postponed to another day.
Excessive feelings of the mother. If, before the study, the mother had any strong emotional experience or she experienced stress, a large amount of hormones can be released into her body, causing characteristic changes ( in particular an increase in blood pressure and an increase in heart rate). The same changes can be observed in the hearth, as a result of which false incorrect results can be obtained on the CTG. If you repeat the test after a while, the results may be normal.
Improper preparation for the procedure. If, before the study, the woman took medications or foods that stimulate the central nervous system or cardiovascular system, this can lead to an increase in the heart rate in the fetus.
Hardware malfunction. Incorrectly functioning sensors can show incorrect results.

Before use, you must consult a specialist.