I've heard that you shouldn't use underwire nursing bras b/c they could cause clogged ducts. Is this true? We're thinking about trying to get pregnant again and the prospect of saggy boobs is depressing. I'm still nursing my 9 month old and I'm not quite so saggy now, but early on it was really hard to ever feel good about my body. I think more support would help, but I've had my fair share of problems too (like clogged ducts) and I don't want that either. So...underwire or no?