You should be careful having an IUD while being poly Kali. They increase the risk of contracting an STD, which is part of the reason I got rid of mine. Sucks too, because they're really convenient.
All types do? If not, which type?
Also, I've never heard this. Source?
Okay, apparently I was wrong. It's something I'd heard about from my poly friends in Eugene, AND my sister was telling me about her friend who is promiscuous being told by her doctor that she shouldn't get an IUD because of the increased risk of STD infection. So that's a relief. Maybe I'll get the Mirena after all.