ACCELERATIONS. Accelerations are transient increases in the FHR (Figure 1). They are usually associated with fetal movement, vaginal examinations, uterine contractions, umbilical vein compression, fetal scalp stimulation or even external acoustic stimulation.
Are accelerations good in pregnancy?
Accelerations are short-term rises in the heart rate of at least 15 beats per minute, lasting at least 15 seconds. Accelerations are normal and healthy. They tell the doctor that the baby has an adequate oxygen supply, which is critical.
Do contractions show on CTG?
If you have CTG before you are in labour you may be asked to press a button on the machine every time the baby moves. At this time you will not be having any contractions so the CTG will only monitor the baby’s heart rate.
Is acceleration normal in CTG?
Normal antenatal CTG trace: The normal antenatal CTG is associated with a low probability of fetal compromise and has the following features: Baseline fetal heart rate (FHR) is between 110-160 bpm • Variability of FHR is between 5-25 bpm • Decelerations are absent or early • Accelerations x2 within 20 minutes.
What heart rate indicates fetal distress?
Canavan, MD, Lancaster, Pa–We define fetal distress as a deceleration of the fetal heart rate to 60 bpm for >2 minutes, unresponsive to medical management such as a change in maternal position, O2, or intravenous fluids, in the face of a medically compromised fetus or abnormal labor; or a deceleration =60 bpm for …
Why does heartbeat drop during contractions?
During uterine contractions, especially during very strong contractions close to delivery, the fetal head is squeezed. This may result in a slowing of the fetal heart rate (a deceleration) during the middle of a contraction, when the pressure in the uterus is highest.
What do accelerations indicate during labor?
Accelerations are short-term increases in fetal heart rate by at least 15 beats per minute (bpm) that last at least 15 seconds. These accelerations occur at different times throughout labor and delivery and are a sign that the fetus has an adequate supply of oxygen.
What causes fetal distress?
The most common cause of fetal distress is when the baby doesn’t receive enough oxygen because of problems with the placenta (including placental abruption or placental insufficiency) or problems with the umbilical cord (for example, if the cord gets compressed because it comes out of the cervix first).
How does a CTG measure contractions?
One transducer records the fetal heart rate using ultrasound and the other transducer monitors the contractions of the uterus by measuring the tension of the maternal abdominal wall (providing an indirect indication of intrauterine pressure). The CTG is then assessed by a midwife and the obstetric medical team.
What is a contraction on CTG?
Contractions – the number of uterine contractions per 10 minutes. Baseline rate – the baseline fetal heart rate. Variability – how the fetal heart rate varies up and down around the baseline. Accelerations – periods where the fetal heart rate spikes. Decelerations – periods where the fetal heart rate drops.
When is Cardiotocography done?
Cardiotocography (CTG) can be applied from 28 week of pregnancy, but its most common use after the 32nd week.
What does an abnormal CTG mean during pregnancy?
Cardiotocography (CTG) is used during pregnancy to monitor the fetal heart and contractions of the uterus. It is most commonly used in the third trimester. Its purpose is to monitor fetal well-being and allow early detection of fetal distress. An abnormal CTG indicates the need for more invasive investigations…
What does it mean if there are no accelerations in CTG?
The absence of accelerations with an otherwise normal CTG is of uncertain significance. Decelerations are an abrupt decrease in the baseline fetal heart rate of greater than 15 bpm for greater than 15 seconds. The fetal heart rate is controlled by the autonomic and somatic nervous system.
How is a CTG used to monitor the fetal heart rate?
One transducer records the fetal heart rate using ultrasound and the other transducer monitors the contractions of the uterus by measuring the tension of the maternal abdominal wall (providing an indirect indication of intrauterine pressure). The CTG is then assessed by a midwife and the obstetric medical team. How to read a CTG
What is the duration of CTG during labor?
Antepartum and on admission to the labor room (admission CTG) the usual (minimum) duration of recording is 30 minutes. Particularly in the third trimester of pregnancy the CTG should be obtained with the mother placed in a left lateral position to prevent vena cava syndrome.
