I am 21 weeks and was told last week I was in the gray area for a shorten cervix at 27mm and to come back in a week. I went in for my scheduled amniocentesis and perinatalologist also check my cervix. In 6 days it went from 27mm to 23mm. He prescribed me progesterone and said that's about all he could do. I then called my midwife who about had an anxiety attack and said to make an appointment next week to be checked again with an OB since I am now considered high risk. What are the chances of bed rest? This is all new to me.