dh has had his sperm test results, basically they confirmed what we were afraid of, count is very low, only 20% of what it should be. GP didn't really offer any advice, said to keep alcohol to minimum (dh hardly drinks anyway) not smoke (dh doesn't) wear loose clothing etc. And that was it. said to go back for a repeat test in three months just to be sure.
so that's it I guess. At least we have a reason now why I've not been able to, and I'd imagine am unlikely to ever conceive again. I guess these things happen for a reason. At least I have an answer now, so can hopefully try to put it behind me and move on.