Quoting adubphelps♥:" It started originally while I was pregnant with my son and it has had points where it has gotten so bad ... [snip!] ... changed now but my IUD didn't even contain hormones. I haven't been on hormonal contraceptives since I was seventeen."
Even if there weren't hormones in it, it messes with what's going on in there. I'm a little fuzzy on how the copper IUD works, but i think it basically kills off any fertilized eggs because our bodies can't tolerate copper very well. Plus something was pulled out of there that's been in there for over a year.
Anyway.. the point being its a foreign body where there shouldn't be a foreign body.
Back when I had a cerclage (cervix stitch during pregnancy), I got all sorts of discharge because my body was trying to fight off something that wouldn't have been there normally. The discharge is white blood cells.
This is also just an educated guess. You could always ask to be swabbed for a yeast infection or BV, but both of those are normally pretty obvious.
If it were me though, I'd at least give my body a cycle or 2 if i wasn't itching or burning or anything weird like that.