I may be doing the math wrong, but wouldn't you count the 8% as being healthy period? I don't know if you would consider it healthy if it weren't active or alive.
To me, I'd think your chances are 8 out of 100.
Sorry I don't have any advice, maybe someone else will chime in. Maybe you can copy your post over on the doctor's board.
You might already know this, but from what I've heard, you should avoid tight-fitting underwear and pants, as well as hot tubs, saunas and other things that are high in temperature
But there are also several supplements that may help. I think vitamin C is one of them, and L-argenine too. There are also supplement blends like FertilAid for Men, which contains a number of beneficial vitamins and minerals. If you do a google search on "supplements" and "sperm quality" (or maybe just "sperm"), you'll probably get lots of information on the different options.
Oh, and one more thing, if the sperm count is low, it is often suggested to abstain for three days before an IUI, or if you do timed intercourse
, only have sex every other day (instead of every day). That will give the sperm supply better time to replenish. And since sperm can live in fertile cervical mucus for 2-3 days (actually up to 5, but I don't think that's very normal), every other day should still get you covered. But you should also not wait too long in between each time. Try to "release" at least once a week :-)