Monitoring your Baby
When your labour starts, so does the monitoring of your baby. This is because labour is probably the most stressful event your baby has ever had to (and possibly will ever have to) cope with. It is vital to keep an eye on how your baby is doing, particularly if we know that your baby has some extra challenges to face on their journey.
Normal heart rate for baby is 110-160 beats per minute. Baby’s heart rate reacts much the same way as ours when we are excited or exercising. It goes up to meet our oxygen needs then down again when we relax. It is normal for the baby’s heart rate to jump around a fair bit if the baby is very active, then to settle down again when they are asleep. These are patterns that we look for in baby’s heart rate that suggest to us that your baby is well and has plenty of energy.
If the baby’s heart rate is not reassuring, we may want to monitor him or her more closely to give us a better picture of how your baby is coping with labour (21). Observing your baby in labour has two formats – intermittent auscultation (listening from time to time) and continuous electronic foetal monitoring (listening all the time).
Intermittent auscultation
Intermittent listening is usually performed at 15-30 minute intervals during the first stage of labour. This should continue into the second stage when the baby’s heart is listened to every 5 minutes or after each contraction. This can be performed using a couple of methods.
- Pinard’s stethoscope – The Pinard’s foetal stethoscope was developed in the 1880s and was in use in the 1950s. The horn is hollow and usually made of wood or metal. The midwife or doctor hears the baby’s heart while they have their ear pressed against one end and the other on your belly. This has mostly been replaced by the hand-held Doppler in current practice. However, it does have its advantages with portability and not needing a power supply.
- Handheld doppler – The hand-held doppler was developed in the 1960s and pushed the Pinard’s out of favour. The advantage of the handheld doppler is that the woman and others in the room can also hear the baby’s heartbeat. It is also light and portable, only requiring battery operation.
Continuous monitoring
Continuous Electronic Fetal Monitoring (CEFM) is usually performed by a monitor called a cardiotocograph (CTG). This can be achieved either externally or internally.
External
In this type of monitoring, women have two straps around their waist, each holding a device that measures different things. One tool is the Doppler ultrasound transducer (similar to a handheld) which monitors the baby’s heart rate. The other is a pressure transducer which monitors your contractions. These patterns are traced onto a graph, and together, they give us an overview of how the baby is coping. The trace of the baby’s heart may indicate when the baby is low on oxygen. While CEFM is reasonably good at telling us that your baby is coping well, it’s not so good at telling us when they aren’t (22). Each CTG trace is interpreted using a set of guidelines and as such is a matter of perspective.
Internal
A Foetal Spiral Electrode is applied to the top of the baby’s presenting part. This device picks up the baby’s heart through their skin, enabling a more accurate reading of your baby’s heart rate. This helps when you are very mobile, and we have difficulty keeping track of the baby’s heart. It is also handy if there is interference when trying to assess your baby from the outside. It may also be recommended if yours and your baby’s heart rate are similar, and we can’t distinguish between the two. While it is slightly invasive, it can be a safer option for your baby in some circumstances. Please discuss the risks and benefits of an FSE with your care provider before consenting to this procedure.
In some hospitals, your contractions may be monitored using an internal device too.
When is CEFM recommended?
These include:
- Meconium liquor (baby has done its first poo in the water he is living in)
- Bleeding from the vagina
- Induction of labour
- Pre-eclampsia
- Prolonged labour
- Epidural
- Evidence by doppler (or Pinard’s) that baby is not coping.
These are just a few of the risk factors that suggest CEFM may be a safer option for your baby.
While it has its place, CEFM during labour is associated with a significant increase in caesarean section and instrumental vaginal births (23).
An admission CTG for a well-woman with an uncomplicated pregnancy when presenting in labour is not indicated unless risk factors have developed (23).
Research suggests that there is no benefit to women or babies in performing this. An admission CTG in the absence of risk factors increases your likelihood of a caesarean section by 20% (23).
We will discuss monitoring your baby with you and obtain your consent before commencing monitoring of any kind.
Dr Janelle McAlpine (PhD), Clinical Midwife
Photo by Eviart used under license from Shutterstock.com