I am a TTC husband, and we have talked to the doc about some issues... There are some things HE can do...
I am trying to figure out how to gently say what needs to be said here...
Uh...
Okay...
He needs to keep his, hmmm. Swimmer manufacturing plant as it were... from getting too warm such as it when sitting for long periods of time, or from wearing overly tight pants / underwear.
The doctor suggested boxers for this issue...
He, and you , need to be somewhat careful in how often you get together and release the swimmers... The body only generates so many in a given time period, and if his swimmer count is low, each and every one possible is needed.
Good Daddy health is a vital concern here as well. So control the weight, no drugs, no drinking beyond very light drinking, no smoking, etc... Certain drugs have been known to impact the Chromosones on the swimmers, and cause birth defects. So no drugs... (not saying your husband is a dope head, but it needed to be said). And of course keeping nutritionally sound, with good diet, and dietary suppliments. I have heard somewhere, and it might be incorrect info, but I was told that the One A Day Men's Health forumla is a good one...
I think most importantly, he has to support his wife in this... Generally being a good husband would help...