Your midwife has a choice of ways to listen to your baby's heart during labour. The most common is via a sonicaid, which is a handheld Doppler and you may be familiar with this method, as your midwife may have used this to monitor the baby throughout your antenatal period. Most sonicaids can also be used under water and so if you are planning a home birth with a pool, you won’t need to worry about keeping moving in order for your midwife to listen to the baby, she can work around you!
The benefits of the hand held Doppler are that you are able to hear your baby's heartbeat as well as your midwife, however some women prefer not to have a sonicaid to listen to their baby, so instead your midwife can use a Pinards stethoscope. This is a trumpet shaped, wooden, plastic or metal item and is placed onto your abdomen with the widest part of the Pinards and the flat part with a hole in the centre is where your midwife will place her ear in order to listen to the heartbeat. This is one of the oldest methods used to listen to the fetal heart. Your midwife should be trained to use this as sometimes sonicaids can break down!
There is another device, which is sometimes used and this is called a fetoscope. It is a little like the stethoscope your midwife uses to check your blood pressure but has an extra attachment shaped like a bar which your midwife places against her forehead and rests this against your abdomen and then listens to the fetal heart via the stethoscope.
The normal heart rate for a baby is between 120 bpm and 160 bpm, although there can be variations such as accelerations above 160 bpm or decelerations below 120 bpm which are normal.
In labour the midwives will listen to the fetal heart rate every 15 minutes whilst you are in established labour, for at least 1 minute after a surge/contraction. This is so we can determine how baby is coping with the labour and most babies cope very well. Sometimes babies become a little distressed and your midwife then needs to evaluate the situation. This will also depend on other factors, such as how far along in labour you are, position of baby, etc. This may present as the fetal heart having decelerations, especially if they are unprovoked, e.g. not caused by cord compression or could present as a Fetal tachycardia where the heart rate is above 160 bpm for a prolonged length of time. Your midwife is trained to evaluate the situation and to act as necessary. This may mean a trip into hospital to evaluate further.
In the last part of your labour, the expulsion phase where baby is being born, midwives listen to the fetal heart rate every 5 minutes, again to evaluate how baby is coping.
Some women like to use their own hand held Doppler’s to listen to the heartbeat themselves, but please be aware that you may not hear the true heartbeat as sometimes your own maternal pulse can be picked up and also you can sometimes hear the cord pulsating rather than the heartbeat.
If you are concerned at all about your baby please contact your midwife.
Post by Debbie Hibbs, One to One Midwife