All about the CTG: contractions and heart rate of your baby

Monitor pregnancy with CTG

The CTG device simultaneously records the heart rate of your unborn baby and the contractions. The test results are presented in two different curves and printed out on graph paper. Based on the peaks and valleys that describe the curves of the CTG, your doctor can draw conclusions about the well-being and the current oxygen supply of your child in the womb. The examination is easy and painless.

The CTG pattern

By recording the child’s heart sounds, your doctor can gain certainty about various parameters. Because the CTG strip reveals how often and regularly your child’s heart beats and whether there are deviations in the heart rate up or down. The range of rashes also provides information about how your child is doing. The duration of the recording is recorded horizontally and your child’s heart rate vertically on the measuring strip. A normal CTG has the following characteristics:

• The average heart rate is between 110 and 150 beats per minute
• The curve is varied
• The average heart rate shows “spikes” up and down (small zigzags around the average rate)
• A recording of 30 minutes shows at least two “peaks” which prove that the child’s heartbeat reacts to external stimuli (e.g. contraction of the uterus).
• There are no recurring “valleys” over the duration of the recordings

Conspicuous CTG

A CTG is considered conspicuous if the average heart rate is below 100 or above 170 beats per minute and the pattern has the same shape and no rash. Several atypical valleys and missing mountains are also an impetus for further controls. Noticeably low or accelerated heart rates can also have very harmless explanations. This is how the heartbeat slows down when your child sleeps. And if it is very active, the heart rate can be increased. To be on the safe side, however, diseases must be ruled out in the event of deviating heartbeat patterns.

Influences on the CTG in pregnancy

There can be a number of reasons why the CTG is different than normal:

• Maternal causes : labor, blood pressure , fever, physical activity, supine position
• Placenta and umbilical cord : gestational age, cord compression, placental insufficiency
• Childhood causes : sleep or wakefulness, activity, oxygenation
• External influences : drugs, medicines, smoking

Deviation from the standard curve

The CTG pattern depends on many influencing factors. Conspicuous patterns do not always mean that your child’s care is at risk. For example, it plays an important role in assessing whether your child is sleeping or awake and moves a lot. If the CTG is abnormal, your doctor will carry out further examinations to be absolutely sure that your baby is doing well and that his care is working properly. In detail it is about:

• Doppler ultrasound : It is used to show the blood flow in the vessels and the development of the heart.
• Fetal stimulation : Your doctor will try to wake your baby up with gentle tummy shaking, acoustic and light-optical stimuli and will check the heart rate again.
• Kineto-cardiotocogram (K-CTG) : A third sensor is used during the CTG to check the intensity and duration of your child’s movement.

CTG possible uses in pregnancy

Based on scientific studies, CTG monitoring is only necessary in the case of an unremarkable pregnancy once the due date has passed . Only if there are risks can early CTG checks help to monitor the child’s care. Regular CTG control is important for the child’s well-being in the following cases:

• multiple pregnancies
• Diabetes or gestational diabetes in the mother
• high blood pressure
• Abnormal ultrasound results
• bleeding
• infections
• Noticeably decreasing child movements
• preterm labour

CTG implementation

The lateral position is best for writing the CTG. Find a position that is as comfortable as possible, as the recording takes about half an hour. A belt with two sensors is placed around your abdomen to record your child’s heartbeat and contractions. The heart sounds are derived via a double ultrasonic pickup. This sends pulsed ultrasound signals to the heart of your unborn child. Your child’s heart reflects these and the ultrasound probe receives them. The examination device automatically records the received signals as a curve. The cardiotogram usually does not reflect the heartbeats one-to-one. For this reason, about five heart cycles in a row are necessary to be able to reconstruct the actual course. Contractions are registered using a pressure sensor. During contractions, the uterus rises against the abdominal wall, causing the pressure sensor to mechanically deflect. This in turn is converted into an electrical signal and recorded in the contraction channel of the CTG recorder. If there is a suspicion of a health risk to the unborn child during pregnancy, your doctor can order a cardiotocography as early as 24 weeks of pregnancy to be on the safe side. How often a CTG is written depends heavily on the individual situation. In some cases, a one-off CTG performed on an outpatient basis, i.e. without a hospital stay, can be sufficient. In the case of a greatly increased risk, on the other hand, permanent monitoring is sometimes necessary. During contractions, the uterus rises against the abdominal wall, causing the pressure sensor to mechanically deflect. This in turn is converted into an electrical signal and recorded in the contraction channel of the CTG recorder. If there is a suspicion of a health risk to the unborn child during pregnancy, your doctor can order a cardiotocography as early as 24 weeks of pregnancy to be on the safe side. How often a CTG is written depends heavily on the individual situation. In some cases, a one-off CTG performed on an outpatient basis, i.e. without a hospital stay, can be sufficient. In the case of a greatly increased risk, on the other hand, permanent monitoring is sometimes necessary. During contractions, the uterus rises against the abdominal wall, causing the pressure sensor to mechanically deflect. This in turn is converted into an electrical signal and recorded in the contraction channel of the CTG recorder. If there is a suspicion of a health risk to the unborn child during pregnancy, your doctor can order a cardiotocography as early as 24 weeks of pregnancy to be on the safe side. How often a CTG is written depends heavily on the individual situation. In some cases, a one-off CTG performed on an outpatient basis, i.e. without a hospital stay, can be sufficient. In the case of a greatly increased risk, on the other hand, permanent monitoring is sometimes necessary. This in turn is converted into an electrical signal and recorded in the contraction channel of the CTG recorder. If there is a suspicion of a health risk to the unborn child during pregnancy, your doctor can order a cardiotocography as early as 24 weeks of pregnancy to be on the safe side. How often a CTG is written depends heavily on the individual situation. In some cases, a one-off CTG performed on an outpatient basis, i.e. without a hospital stay, can be sufficient. In the case of a greatly increased risk, on the other hand, permanent monitoring is sometimes necessary. This in turn is converted into an electrical signal and recorded in the contraction channel of the CTG recorder. If there is a suspicion of a health risk to the unborn child during pregnancy, your doctor can order a cardiotocography as early as 24 weeks of pregnancy to be on the safe side. How often a CTG is written depends heavily on the individual situation. In some cases, a one-off CTG performed on an outpatient basis, i.e. without a hospital stay, can be sufficient. In the case of a greatly increased risk, on the other hand, permanent monitoring is sometimes necessary. To be on the safe side, your doctor can order a cardiotocography as early as 24 weeks of pregnancy. How often a CTG is written depends heavily on the individual situation. In some cases, a one-off CTG performed on an outpatient basis, i.e. without a hospital stay, can be sufficient. In the case of a greatly increased risk, on the other hand, permanent monitoring is sometimes necessary. To be on the safe side, your doctor can order a cardiotocography as early as 24 weeks of pregnancy. How often a CTG is written depends heavily on the individual situation. In some cases, a one-off CTG performed on an outpatient basis, i.e. without a hospital stay, can be sufficient. In the case of a greatly increased risk, on the other hand, permanent monitoring is sometimes necessary.

CTG under birth

During the birth, CTG monitoring is the safest method of detecting an undersupply in your child in good time: Because the device immediately registers the drop in the child’s heartbeat, appropriate measures can be taken immediately. The first CTG is written when the baby is admitted to the delivery room. Depending on whether there is a risk for your unborn child, it is repeated regularly after 30 minutes to two hours. A continuous CTG recording then takes place during the late opening and expulsion phase so that the safety of your child is guaranteed in any case. In the case of a high-risk pregnancy, a CTG is taken throughout the opening and expulsion phase. In well-equipped clinics, special CTG devices are used restricting the mobility of the pregnant woman as little as possible. In this case, the CTG signals are transmitted by radio.