iud

ive been using iud for almost 4 years after I gave birth for my son. I frequently feel severe cramping and bleeding in between periods and oftentimes I feel pain during intercourse thats why I had to visit a doctor last november. I found out that I already had a mild pelvic inflammatory disease. There was medication and after that I asked the doctor if its still good to have my iud still inserted. she said its ok but I doubt if it is so.. coz im afraid I could have that infection again. so i am trying to ask if its still advisable to keep my iud inserted? or I have to remove it? thank you