Wouldn't do it!
A belly ring is probably able to be sterilized by boiling.
If there are plastic parts, jewels, cracks and crannies and crevices, then you could have a problem. Boiling, pressuring and other methods could probably be used to sterilize the ring, but why take the chance. Invading the integrity of theskin of the body should be done carefully, maturely, and for good reason.