I have the Angelsounds monitor which was really good value at £20. I heard the heart beat at 8+5 and it's started to get louder and louder. Yesterday I listened to it for a good 3/4 minutes before I turned it off. I could have listened longer, but I remember how my son used to kick dopplers when he was a bit further on in gestation, so I imagine it's unpleasant for them - although maybe that's just when their hearing develops and the bouncing sound waves make them uncomfortable. This little one didn't move away from the doppler last night as I was able to get a really long listen, long enough to calculate the heart rate - that's the one downside with the Angelsounds, you don't have a monitor, but I find it easy enough to time ten seconds, count the heart beats and then multiply by 6.
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