Amniotic / Cervical Sludge

Does anyone have experience with this? I have always had very difficult pregnancies and this time it has been pretty uneventful except for one scare that I thought was amniotic fluid but was not. Yesterday I was scheduled for a cerclage but due to not doing several tests ahead of time they sent me to get cervical length check. During the vaginal ultasound they found “sludge” which can indicate infection, blood, or other things forming together . The scariest part is it can cause preterm labor and I’ve already lost 3 precious babies late in pregnancy. They put me on a run of antibiotics but I’d love to know if anyone has dealt with this. I am 15 weeks