Mine was 177 at 12 wks. I asked the tech if it was high and she said it was probably like it because the baby had been jumping around so much during the u/s. Call your doctor on Monday just to calm your nerves but in the meatime don't worry!
(The tech wasn't concerned at all btw and my doctor never said anything about it later).
I wouldn't be concerned unless your doctor is. Do not be surprised if the heartbeat decreases the further along you get. My doctor told me this might happen, and my baby started at 160s in the 7 week range and now is measuring in the 140s at 16 weeks. Do you have your own doppler? They measure the heart rate (it's somewhat accurate) so maybe you can see if the heart rate stays in the same in multiple uses.
Re: Heart rate to high?
(The tech wasn't concerned at all btw and my doctor never said anything about it later).