Hi Liss,
I have incomp cervix which my cervix shortens down to the point of real prem labour. Feel relieved that they have picked it up and are monitoring it. My 18 week us measured my cervix at 1.6 and unfortunatly within a week my waters broke BUT this was due to a doctor telling me everything was fine and not to worry.In the next few weeks dont lift heavy items or put any strain on yourself including constipation pushing and no bding or intimate contact.

A high risk specialist that managed my daughters pregnancy liked a cervix to be over 2 if below usually hospitalisation and a stitch put in place. My daughters pregnancy was a cervical stitch sucess story.I had a general at 14 weeks and had a stitch placed high in the cervix that was taken out at 37 weeks.

Some people do have shortened cervix and it is hard to tell whether it is shortening or just genetic. In the next two weeks they will be able to tell if it continues to shorten. Any brownish mucus discharge call your Obst. A stitch is better to be put in before it becomes an emergency situation of bulging waters.
Relax and take good care of your self, the answers will be there at your next ultrasound
Bec