cervix..problems during pregnancy...help

long story short...i have had some problems during pregnancy ...i am 23 weeks...yesterday i went for my check up and they did a transvaginal ultrasound....
i had one 4 weeks ago and my cervix measured at a 3.....now 4 weeks later it is 1.6 (with preasure)...obviously the doctor was concerned and said to come home on full best and come back on thursday to see if it got any shorter. if so i may need to spend the rest of my pregnancy in the hospital. so we shall see....
what is a cerlage? is that for a short cervix? or one that is open? or is that the same type of thing? any feedback would be appreciated!
just curious any one recently get a measurement lately and how long was it and how far along are you?  

A cerclage is where they put stitches in the cervix to hold it closed.  It's done to prevent an early delivery.  

I am so sorry to hear about this for you.  I have the same problem.  I had my daughter (who is now 5) at 26 weeks because of an imcompetant cervix.  Same thing, I went in and my cervix was getting shorter with pressure and so my doc did the cerclage.  It was fine, not alot of pain at all and didnt take long at all.  The cerclage is what the other woman said, stitches to hold it closed and help prevent it opening early.  This pregnancy, my doctor did the cerclage as soon as i hit my second trimester to catch it before it started to open.  I had to go on complete bedrest with my first daughter, no sex, no ******s what so ever.  That was all so hard.  I thought my doc was being paranoid but she wasnt.  When my daughter came early even with the cerclage and bedrest, I was thankful she had been so thourough.  Good luck with this.  It will be a challenge but worth it in the end.  You can write me if you have any other questions.  I can probably answer most anything about the subject. :)