Made for iPhone Hearing Aids
Check out this link from Apple's own website concerning HAC, or Hearing Aid Compatibility.
"Apple is working with top manufacturers to introduce Made for iPhone hearing aids that will deliver a power-efficient, high-quality digital audio experience (Requires iPhone 4S or later and iOS 6 or later). Made for iPhone hearing aids should be available from top hearing aid manufacturers starting in 2013."
This may also be of interest:
"Bridge" accessories for audio streaming
Some hearing-aid manufacturers offer special "bridge" hearing-aid accessories that receive audio through Bluetooth from the iPhone and retransmit that audio using proprietary wireless audio-streaming technologies built in to some hearing aids. Check with your audiologist or hearing-aid manufacturer for more information.
Q: Would you patronize a streetwalker?
A: No, I would treat her as an equal.