I went for my 6 week ultrasound to see if we could see a heartbeat yet (went at week 5 and it was just a yolk sac - which by the way the dr said is all they expect that early).  The tech saw the heartbeat (112) and said based on the size of the baby, the heart must have just started beating that day or the day before!  First of all- how crazy is that???  One day there's no heartbeat, the next there is!  Just goes to show how quickly things change in there!  I'm coming off of multiple early losses so my RE is monitoring me weekly.  Had I gone the day before, I may have not seen the heart yet and been emotionally wrecked.  Going for an early ultrasound is something most of us want but remember, sometimes it's just more stressful. My recommendation is if you haven't had problems in the past wait until 6 weeks+ when you can see the heartbeat.  It makes sense that the heartbeat just started because I went from feeling sort of barely pregnant to feeling like 💩.