At 22 weeks i had 0.7mm of cervix shut the rest was funnelling, they gave me progestrone pessaries but too late for stitch. by 25 weeks my cervix was open and then 26 wks my waters broke. I think 3.2cm is actually normal myself and should be fine,
It s such a worrying time, i know, but if your baby is born early there is so much they can do. I wish you all the best xxx