I'm repeating exactly what my midwife said in my original post, I highly doubt she is wrong and the reason they still use them is because they are fully trained to differentiate between the sounds whereas to the untrained ear they sound the same!! She had 3 patients under her care at 20+ weeks who reported reduced fetal movement so they grabbed the Doppler, THOUGHT they heard the heartbeat when in actual fact it was the placenta, by the time they realised baby was no longer moving, it was too late!! So the proof is right there, like she said to me, if your buying for reassurance and you feel something is wrong, don't reach for the Doppler, reach for the phone.
- yes the placenta does have a whooshing sound too, which is the only reason you can tell a difference however some people have been known (including myself) to think that because they can hear a whooshing sound and a fast "heartbeat" that's quietish that baby must just be say funny etc.
Like I said, I'm repeating what the midwife told me and at a later date it could be the difference between life and death if baby comes into distress.