I had bought fertility books and that is how I convinced dh to take supplements when we got pregnant with Megan. Once I read him little pieces of the book about how different vitamins help sperm then he was understanding how important his sperm are in this process. After our 2 miscarriages I got the book out again & we started taking the same type of things again.
When we got pregnant w/ megan I had him taking multivitamin for men, extra zinc, vit c, vit e, & vit b complex (it has folic acid & bvitamins)
When we got pregnant w/ 2 miscarriages dh was taking only multivitamin
Since miscarriage #2 he now is very willing to take anything or eat anything I tell him too - but he still likes to complain a bit - he takes multivitamin for men, fish oils, zinc, vit c,e, super b complex, coq10, and amino acids.
He wont take them unless I put each one in a little cup for him & then remind him til he takes them.
If he refuses I would make sure you are cooking as healthy as possible (which is a good idea anyway!) Fish vs fish oil (my dh wont touch fish), blackberries, blueberries, strawberries, plums, garlic, broccoli, & red peppers are all things I read are good for dh while ttc.
Vit C - any citrus, cherries (also has iron), broccoli, grapes, kiwi, pineapple, asparagus (also has folate), peas (also has beta carotene), potatoes
Eggs have vit a, b vitamins, iron
Nuts & seeds vs. chips to snack on, brown rice, bran, whole grains in general (even oatmeal if he isnt a fan of other things)