No. I've had my belly button pierced for eight years and never had a hernia. So I have a hard time believing that a belly button ring could cause a hernia. It can cause an infection but it can't cause a hernia.
I would say no. A hernia is inside your stomach and you have a lump around your belly button. So my guess would be if you have a hernia, you can't get your belly button pierced.
Yes. There are different types of hernia. One can be next to your belly button. One can be around your belly button. I don't know about the other types.
A belly button ring is a body piercing placed in a cauterized area of the belly button.
It will get stared at more often.