Since you have already seen a doctor, then either try new things to get him going in sex or see another doctor and see if they will perscribe him anything.... (if your trying to have children another thing you might want to do is get him to masterbate and right before hes done start having sex thats the only thing I can think of that would probably work to having another kid...)

How often does his endocronologist check his test levels. If his levels are in the average range then he it should not be a problem. I had a similar problem but I have not had the cat scan yet.... Good luck