My husband is 29. He also had large testicles. After trying to conceive for a year a semen analysis showed he wasn't producing any sperm. It was directly related to his CAH and the fact that his med levels are/were completely wrong. He found a new endocrinologist who is trying to return all of his hormone levels to normal levels while trying to get him on the proper dosage of meds.... (it's been another long year)!!!!!! During this time his testicles have notiably decreased in size. (still no luck with sperm production) I'm not sure if this will help.... there's not a whole lot of information on this, nor many people with this problem. He should probably mention it to his endo. Our's told us the two are directly related. Kari I'm not sure if this is helpful