short cervix

Amber
I am 21 weeks pregnant. We had our anatomy scan today. They also measured my cervix which is short. They want it around 2.5 and I was at 2.2. Put me on rest and progesterone. Go back next week to measure it again. Has anyone else had this problem? Did rest and progesterone help or was there something else that worked? I'm not really worrying yet but my OB is also having us see another doctor. I'm just wondering if my doctor believes these steps aren't going to do what he wants and is preparing us for alternatives with someone else. Thoughts on that as well?!