Repeating misscarriage and fetal deaths

Hi ladies,
I hope you are all doing fine and can have your babies in your hands asap.
I had prior 4 miscarriages : 1 clinical and 3 of them were biochemical. After couple of years, we've tried <a href="">IVF</a>-ICSI and 2 5day embrios transferred. I was having Clexane 0.4 each day and 1000mg Methylfolate and low dose Aspirin. In my genetics, I have Homozygote Mutant C677T. 
We saw heart flutter and hb of 125bpm a week ago. Now I'm 8 weeks 5 days and we went to obygn and they have told me that there is no fetal cardiac activity. (Heart beat of my baby has stopped) Now it's my 5th fail as a missed miscarriage (silent miscariage)
I can't have a baby, I miscarry or unfortunately heart stops while growing :((((( 
Tomorrow I'll be having a D&C. Which way shall we go through? They already drawn my and my husband's blood for Periferic Cariotip and we are planning to send our baby to patology too. On the other hand, there are five units of 5th day frozen blastocysts are waiting at the bank but we did not do any PGT's for them. If I have another transfer of two of them, I afraid of miscarrying again or hb can stop and we may fail again.
If you had any experiences in the past? I would appreicate if you can show me a way as a pathfinder for God's sake?
Thanks a lot!