I've had the bruising too. I didn't realize there was a connection to the mirena though until more recently. They are small and pop up in some of the weirdest places that you wouldn't expect to see a bruise. I had one on my bottom once. Right now I have one under my forearm. They are small like the size of a thumbprint. I had bloodwork done in August and everything came back normal so I just assumed I bruised easily. I'm very pale and have always bruised fairly easily.