I received a message from a woman who was considering the possibility of having multiple nipple piercings:
So I got both my nipples pierced quite a while back. Because of my profession I can't get any visible piercings and I'm not quite ready yet to go into genital ones. So that's why I was thinking of getting my nipples pierced again
What are some of the perks and risks of getting additional nipple piercings? My piercings are also not horizontal, but diagonal. I let my piercer do this on purpose, for aesthetic reasons. Is it possible to put the second pair straight on there, so it makes a diagonal cross?
To some extent your anatomy will determine appropriate (or possible) locations for added jewelry. If the second piercing would end up too close to the surface, or too far into the areola, those are potential issues. Also there's another consideration, depending on how much space you have, and therefore how much tissue is in between the jewelry: it can pinch on the interior. And, if the jewelry is quite close together, it is not uncommon that due to pressure, the skin in between thins and dissipates, and the jewelry rests metal to metal inside. This is not necessarily a bad thing, especially if you experience discomfort from interior pinching.
The drawing from my book, The Piercing Bible, shows the appearance of a double nipple piercing in an "iron cross" formation.