Slow doubling but high beta! so worried!

Jill
Hi Everyone,
I am looking for some success stories in regards to slow doubling betas! We were so excited yesterday to get our result from 10dp5dt of 621 today was 12dp5dt only 998! That's a doubling time of 70 hours and only a 60% increase! We are so worried! I am impatient person so the wait until the next beta is going to be torture! I am trying to hang on to the fact that our first and second betas were drawn at different labs. This is where my tiny sliver of hope lays. Also, in others similar experiences.
Has anyone had slow doubling betas resulting in a live birth?
Any positive stories would really help right about now :)
Thanks! xoxo