Just went for our 2nd u/s and the hear beat was measuring at 68 bpm

Things aren't looking so great because it is so so low. No bleeding or spotting yet though. Anyone have similar stories?
BFP 5/08/13 -- EDD 1/15/14 -- slow hb@7wks d&c 6/07/13
BFP 8/12/13 -- EDD 4/20/14 -- no fetal pole @7wksnatural m/c 9/16/13, cytotec 10/17 & 10/22 BFP 11/26/13 -- EDD 8/07/14 -- Born 7/24/14!
Re: low HR at 7 weeks
At 6w3d I went for an ultrasound, one of our twins didn't have a heart beat, and the other had one of 68 Bpm too actually. I stayed optimistic, after I grieved and mourned for two days, I tried to stay positive. 10 days later I began bleeding and birthed both of them.
I am so very sorry this is happening to you. Keep in mind that ultrasounds create heat, and this heat can affect the baby and sometimes cause a drop in heart rate. As well, you could possibly be earlier and the heart just started beating. There is no way to know what will happen
Right now you are pregnant and you love your baby. Have a bath, rub your belly, tell your baby you love him or her and trust him. That is what helped me tremendously. I laid in the bath and just held my hand over where my babies were, and told them I loved them and trusted them.
I am so so sorry again, please keep us updated.
Emma Kate - born 10.16.03 @ 29 weeks, weighed 1lb 13oz and 13.5" long.
TTC #3