This might be a stupid ? but

I had the Mirena (or however its spelt) since May of last year.

In July I quit having a period and to this day I have not had one (so over a year now)

But....I was wondering, Can you still get pregnant on the IUD when you no longer have a period?

You can get pregnant any time. You don't need a period to ovulate, you need to ovulate to have a period.
Hormonal BC's for the most part have a 99 percent success rate.
That is why someone can get pregnant before they even get their period.

My fell out and i wouldnt of had any idea it happened if DH and I hadnt been messing around. He found it and was like WTF is this   lol All i could say was "smurf, that's my birth control!" It was a mood killer