A major part of midwifery care during labour is listening to and recording your baby’s heartbeat to help identify if there are any problems.
Most babies come through labour without any problems, but there are a few babies who run into difficulties. The best way of finding out which babies are having trouble is to listen to every baby’s heartbeat regularly throughout labour.
What is the midwife listening to?
The normal range for the rate of the baby’s heartbeat is between 110 and 160 beats a minute, although this can be higher or lower without meaning that the baby is in difficulty. The variation in the baby’s heart rate may be caused by the womb contracting, which affects the blood flow to the placenta (afterbirth). This is normal and most babies cope without any difficulty.
If your baby is not coping well, this may well be reflected in the pattern of their heartbeat.
As well as monitoring your baby’s heartbeat, your pulse (heartbeat) will also be checked in order to tell the difference between them.
How is my baby’s heart rate is listened to and monitored?
Your baby’s heartbeat can be listened to in a number of different ways, either at regular intervals (intermittent auscultation) or continuously (electronic fetal monitoring (EFM).
Intermittent auscultation - is where your baby’s heart beat is listened to at regular intervals with either a pinard or a small hand-held ultrasound device called a Doptone. If you are healthy and have had a trouble free pregnancy this is the recommended way of listening to your baby’s heartbeat during labour. When pregnancy and labour are uncomplicated, research has now shown that the use of continuous Electronic fetal monitoring does not improve the outcome for the baby.
Midwives and doctors listen to your baby’s heartbeat over a full minute, every 15 minutes once your labour is established and then more frequently as you get nearer the birth.
Continuous Electronic Fetal Monitoring (EFM) - is where your baby’s heart beat is listened to continuously using a machine that produces a paper printout called a cardiotocograph (CTG). The EFM machine works by having two pads (transducers) each about the size of a drinks coaster, held in place on your abdomen with two elastic belts. One is placed towards the top of your abdomen, so that is lies over the upper end of your womb(uterus) to pick up your contractions; the second one will be positioned on your abdomen, over the area where your baby’s heartbeat can be heard best.
The information received by the transducers is converted by electronics within the machine to produce a graph. EFM using the two external transducers is a non-invasive method. Sometimes, for reasons which would be explained to you, the baby’s heart beat is picked up by using a small electrode which is placed onto the baby’s head, and attached by a thin wire to the machine, and this would mean you would need to have an internal (vaginal) examination in order for this to happen.
Which method will be used?
If, when listening to your baby’s heart beat with a pinard stethoscope or doptone device, your midwife or doctor thinks there may be a problem, they may recommend that you change to EFM. If you are in labour at home, you will need to transfer to the Central Delivery Suite for EFM.
If you have had problems during your pregnancy and the midwives or doctors have some concerns about how your baby will cope with labour, they may recommend the use of EFM as soon as you have regular contractions and your labour is becoming established. National guidelines (NICE - National Institute for Clinical Excellence) recommend the use of EFM in the following circumstances:
- Your baby (from external assessment) seems smaller than expected
- You have high blood pressure
- You are expecting twins or triplets
- You had a caesarean birth with any of your previous pregnancies
- Your labour has been induced for any reason on this list.
- Your baby is overdue (more than 42 weeks)
- Your baby is premature (before 37 weeks).
Other factors that may affect your decision about which type of monitoring to choose are the method of pain relief (intermittent or continuous use of EFM is recommended with an epidural), or a ‘drip’ (infusion into a vein) to start (induce) or speed up labour. In these instances your midwife will recommend EFM.
EFM will also be recommended in the following circumstances:
- You have a health problem such as; Diabetes; problems with your heart or kidneys or infection
- Your baby is breech presentation (going to be born bottom first).
What are the benefits and risks?
Listening to your baby’s heart beat in labour is standard normal practice and is for the benefit and wellbeing of you and your baby. In certain situations, as described earlier, the extra information provided by EFM may be appropriate to further monitor your baby’s wellbeing. EFM in itself has no known risks, but when internal EFM is used there may be a very small risk of infection. EFM may also restrict your mobility in labour which may not be helpful, although there is no need for you to be immobile.
If your baby is being monitored by EFM and it shows a problem with the baby’s heartbeat, you may be offered a test called fetal blood sampling. In this test a small sample of blood is taken from the baby’s scalp and tested for the amount of oxygen. This test is performed during an internal examination and it is recommended as being the most accurate way of detecting whether your baby is in difficulty. The doctors can use this information to decide whether your baby needs to be delivered by caesarean birth or it may prevent an unnecessary caesarean birth.
Do I have a choice on the type of monitoring?
It remains your choice as to what kind of monitoring you have during your labour. It might be helpful to consider:
- The hand held doptone can be used whatever position you are in; you can therefore move around as much as you like during labour and it can also be used if you are labouring in water.
- EFM will limit your movement, although you can stand up or sit in a chair, but you may need to ask your midwife for assistance. However, there are electronic monitors available, sometimes, which use a “telemetry” process to pick up the baby’s heart rate and your contractions and this means you will be able to be more mobile e.g. walk away from the monitor, as there will be no leads coming from the transducers around your abdomen (tummy).
If you would like to know more about monitoring your baby’s heart beat during labour please discuss with the midwife.