Ways to Monitor Baby in Utero: Fetal Heart Tones
One of the many ways that midwives keep out-of-hospital birth safe is by monitoring how the baby is doing in utero. One of the ways that a provider can monitor a baby is by listening to fetal heart tones. There is a variety of ways to do this and in this article we will discuss what some of these variations are.
Babies in utero have a much higher heart rate than their adult counterparts. The normal fetal heart rate range is anywhere from 120 - 160 beats per minute. Fetal hearts begin beating at around 6 and a half to 7 weeks of gestation. Their hearts are very small at first, which can make it challenging to hear. The earliest way to detect heartbeat would be through ultrasound. This is because even if it cannot be heard, heartbeat can be seen as soon as it starts beating.
In midwifery, one of the most common ways to listen to heartbeat is through what is called a Doppler. A Doppler is a handheld machine that has a a wand attached to it . The wand is placed on the belly and can pick-up the sounds of the fetal heart and plays it on the handheld machine. On the machine portion of the Doppler, there is a small screen that will show the amount of beats per minute of the detected fetal heart. The earliest that the Doppler can pick up the sound of a fetal heart is 8 weeks.
Another device used to obtain fetal heart tones is called a Fetoscope. A fetoscope looks similar to a stethoscope. It has ear pieces and tubing that goes from the ear pieces down to what looks like a cone. The cone at the end of the tubing is placed directly on the belly,
on top of where the baby's back is located in the uterus. It magnifies the heartbeat through the tubing and up into the ear pieces. The earliest a heartbeat can be detected using a fetoscope is around 20 weeks gestation. A Pinard horn is the same as a fetoscope but does not having the tubing. Instead of having the tubing that allows the sound to travel up to the ear pieces, the provider would place their ear directly on the cone and be able to hear through the ear that is against the cone. This piece of equipment also takes till roughly 20 weeks to be able to pick up heart tones.
Sources:
Photo #1 Credit: https://www.pexels.com/photo/blur-chart-check-up-curve-415779/
Photo #2 Credit: https://cascadehealth.com/allen-type-fetal-stethoscope-fetoscope
Photo #3 Credit: https://www.accessdiagnostics.co.uk/products/metal-pinard-fetal-stethoscope-pinard-horn
Photo #4 Credit: https://www.verywellhealth.com/fetal-doppler-5119457