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Baby’s Heart Rate During Labour
Monitoring your baby’s heart rate during labor? Don’t be surprised if your healthcare provider does this. Fetal monitoring during labor became a universal norm with the invention of the electronic fetal monitor or EFM in the year 1958. The motive behind applying an EFM is to allow your care provider to see how your baby is coping during labor and tackle any potential complications well before time. While the EFM was invented to handle high-risk pregnancies and help high-risk babies, the machines are now being used widely irrespective of the risk status of the mother.
Why should fetal heart rate be monitored?
The main reason to monitor a baby’s heart rate during labor is to detect any fetal distress, which could impede adequate oxygen supply to the baby. Early detection can help your care provider to make a timely intervention and prevent complications such as seizures, cerebral palsy, and even death. However, different care providers might have different definitions of fetal distress depending on how they regard the fetal heart rate. It might be a matter of concern if your care provider chooses variations in your baby’s heart rate as a sign of fetal distress.
Whatâs the normal heart rate during labor
A full term baby’s heart rate should range between 110 and 160 beats per minute (bpm). Your baby might have trouble coping with labor if the heart rate is higher or lower than this range. Some factors could influence your baby’s heart rate.
Your baby’s fetal heart rate is governed by several physiological mechanisms, namely cardiac mechanisms. By observing the fetal heart rate, physicians can also infer the condition of the fetal brain.
How is the fetal heart rate monitored?
The fetal heart rate is monitored using various devices:
- Doppler ultrasound: It is a tool that the physician holds in her hand and places on your belly. The tool transmits the fetal heartbeat.
- Fetoscope or Pinard: It is quite similar to the traditional stethoscope.
- Electronic fetal monitoring: It consists of two belts that are placed on your belly. The belts have a small monitoring device, which works continuously.
- Internal fetal monitoring: This is used only when your waters have broken because it involves inserting a small electrode into your baby’s scalp.
How frequently should fetal heart rate be monitored
One should comply with the guidelines. A Doppler or Fetoscope monitoring can be done intermittently, which is every 15-30 minutes during the first active stage of labor.
EFM is the most commonly used method in hospitals and can be used either continuously or intermittently. It can be used every 30 minutes in the active first stage of labor and every 15 minutes in the second stage of labor. However, an EFM can increase the risk of using forceps or vacuum during birth. It could also increase the chances of a c-section birth and therefore are best suited only in case of complicated pregnancies.
Different kinds of heart rates
The baseline heart rate is the average fetal heart rate noted during a ten-minute period with specific exclusions. The baseline heart rate helps one assess your baby’s heart rate during labor and as to how it is coping during labor.
Accelerations:
Your baby’s heart rate could rise to at least 15bpm for about 15 seconds. These normal rises of heart rate are called accelerations and usually, occur at different stages of labor and birth. Accelerations indicate that your baby has a good oxygen supply and is coping well. In case accelerations are not observed, then they can induce accelerations by pressing on your baby’s head through the cervix with their finger / rocking your belly gently/ delivering a short burst of sound to the baby.
Decelerations:
It refers to your baby’s heart rate dropping momentarily. There are three types of deceleration:
Early decelerations:
When the baby’s head is compressed just before birth as it descends through the vagina, or when the baby is in a breech position and the head is squeezed during contractions, it could classify as early deceleration.
Late deceleration:
These might occur as soon as a contraction has finished or might begin at the peak of a contraction. Late decelerations are smooth and might be characterized by shallow dips that reflect a contraction. Your baby might not be handling labor well if the heart rate doesn’t recover after the contraction.
Variable decelerations:
Common in most labors, these are the irregular dips in the fetal heart rate when the baby’s umbilical cord is compressed. It could be a cause of concern if the pattern repeats. It might also be an indication that the baby’s oxygen and other important nutrients are being compromised.
What Happens If Baby Isn’t Coping?
Your care provider might draw a tiny sample of blood from your baby’s head for testing. The oxygen levels will indicate how your baby is coping. You could also be put on IV fluids, so you are well hydrated. If you have been reclining on your back, you might also be made to change positions to reduce the pressure of the uterus on the major vein of your body. You should be on good oxygen levels too. If these changes are not implemented, your care provider would want to deliver the child as soon as possible. If by this time the cervix is fully dilated, the doctor might use forceps or ventouse to bring the baby out. If the cervix is not fully dilated yet, you might be wheeled in for a c-section.
While fetal monitoring has become common and might be instrumental in analyzing how your baby is coping during labor, it is up to you to decide if you want fetal monitoring to be performed. Discuss with your doctor if you want to proceed with it.
