The amount of medication should play no role in his sperm count. I have done some research on the Reverse vasectomy.. This is what I am finding..
The success rate varies based on several factors. Time from the vasectomy certainly helps to predict how likely it would be to be able to put the two ends of the vas deferens back together, however, getting return of sperm into the ejaculate does not guarantee pregnancy, so pregnancy rates typically vary from 30 to 70 percent, whereas potency rate, that is the return of sperm, can be as high as 95 percent.
Scarring can occur at any time after a vasectomy reversal although it typically occurs within the first six months. Therefore, even if there was sperm in the ejaculate after six weeks, it is possible that scarring could occur later on. We typically offer sperm banking in case late scarring does occur.
The sperm quality should return to normal 3 to 6 months following a reversal as it takes that long for the testicles to make new sperm. However, the count and the motility may be lower after reversal due to partial blockage or scarring.
We typically recommend checking every 3 months, and we offer sperm banking based upon the quality of the sample. In most series, the chance of scarring is approximately 7 to 10 percent in the first 1 to 2 years following a successful reversal.
You can read more here too
http://www.vh.org/adult/patient/urology/faq/vasectomyreversal.html
http://urology.jhu.edu/surgical_techniques/vasectomy/
So other than that information and the included links I added in the 1st reply to increase sperm count.. thats pretty much all I know. You may want to call his doctor to see what he suggest since they know his history and with him doing the reversal to begin with.. to get the highest chance possible. I really wish there was a magic procedure or concrete advice I could give.. but he's come this far and you too.. so the rest will have to just wait and see.. try not to stress over it too much.. I'm sure he can sense your stress and frustration which may not be helping him either.. other wise.. try to relax.. do what you can from the links I gave above.. and what will be .. will be.. I wish you both the very best of luck... Hopefully... you both will be parents this time next year!....
If you need anything let me know.. Once again.. Good luck Hun..