Bleeding after sex with an IUD?

Has anyone else experienced light bleeding for a few hours after sex with an IUD? I'm trying to figure out if this is normal. Or, could it be a consequence of the large number of blood thinners I am prescribed or an accident of my partner's Prince Albert (it's a piercing; Google it if you are curious, but not at work) colliding with the IUD and causing the IUD to scratch me.