Here's the down-low. If you're amply endowed, that whole "don't wear a bra" thing is a crock of shit. When I had mine pierced, I had to wear a sportsbra for a week (Yes, I did wash it every night to keep all the goobers off my fresh piercings) before I could even THINK of reaching for my normal bras. I found that the constant movement of my breasts (I was a DD at the time) when braless only aggrivated my piercings; I went without support for one day and boy did I have to make up for it for the next several weeks with the salt soaks...<p>
In any case, breastfeeding while you have your nipples pierced is no big deal; Just remember to remove your jewellery when you've got the kid attatched and you'll be fine.<p>
For more information on piercings, risks, and pretty much anything associated, I highly recommend
http://www.bmezine.com. This question has been brought up in the "Ask BME" section many a time, and the Glossary/Risks sections are a veritable treasure trove of information.