I'm using a home Doppler and I *think* I'm only 7+5 so this would be quite early. You'd probably need headphones to hear this. I'm not talking about the "swish...swish" sound, but the "wompwompwompwomp" in the background. I'm wondering whether this could be a fetal heartbeat. When I take my own heartbeat now, it is between 58 and 62. When I tap out the wompwomp sound I'm getting 168 or so. I just have an app where you tap the screen with every beat you hear.