I suppose I am one of the sucessful stories in this department.
I prev lost 2 preg at 20 weeks before they decided that I was worth the risk of infection with a cerclege. Mine was done at 13 weeks and held with no shortening at all till 37 weeks.
The specialist that did mine had his own technique which placed the stitch high up in the cervix, and did alot of this procedure. I am 100% sure with a normal stitch I may not of got as far as I did.
Good luck do your research and my prayers are with you and your partner to get thru this terrible loss

B