Cervical pessary?!

Has anyone else had this?? I've had it in for 2 weeks now and I get it taken out when I'm 37 weeks (4 weeks away).

When they put it in I was 1cm dilated and 50% effaced. I feel like when the doctor takes it out I will go into labor soon after. My due date is march 22nd but I'm feeling like hes gonna come not too long after she takes it out. I was given steroid shots to help his lungs develop incase he does come early. If anyone else has had this, how soon after it was taken out did you go into labor??