A scan at 13-14 weeks will show if you have a shortened cervix, my radiographer gave the all clear to my obst which now looking back had a length of 1.6 cm That is short for that amount of weeks, I lost 2 babys in the second trimester with results like the one mentioned previously STILL to have obst say....ahhh its too hard to say if you have i/c.
Obst that dont do stitches all that much rather not do them and risk infection. Find someone who deals with prem labour, multiple births and they will give you a honest opinion. Good luck I had alot of IVF and D&C's , hysteroscopys and laps which I am sure is why I was given a second hand cervix.

ETA: Anything under 2cm is short ....with my stich in my cervix stayed at about 2.5 - 2.7, anything under 2 I was hospitalised on bedrest