I've never had an IUD, so I can't speak to that, but I do get migraine auras without headaches. I've had them since I was in my early 20's, but since I've gone through menopause, I noticed that I rarely get them anymore. That made me wonder if they were hormone related.

The symptoms of my auras have been exactly what you described, though not all of the symptoms necessarily occur with every aura of mine. As far as scent sensitivity, I also smell things that others can't while in the midst of one. For example, I have smelled Flintstone vitamins, wet dirt, baking cookies, and cotton candy at different times at the start of many auras. When I've been with other people at the time this occurred, they couldn't smell anything, and there was nothing nearby cooking or that could have explained those scents.

I also get the zig zags, blind spots, and light sensitivity. Sometimes, just looking at a certain pattern has kicked off an aura. One time, I was in someone's yard that large trees with pinkish-white petals. The petals covered their entire driveway. As I walked towards the driveway, then looked down at the petal-covered driveway, I started feeling a bit dizzy and then the aura started.

I used to get these aura a lot and took medication for it, but since menopause, I've only had a few auras, and they haven't lasted that long. They've definitely calmed down tremendously on their own.