Hey! My man is super excited about TTC and gung-ho on doing it like... yesterday. Ha ha, so this is a worry I have with him, too. I just try to find shorter articles for him to read, bring up pregnancy conversation and really just wait for him to ask questions (which he does more frequently than you would think of a man) and I try to be as correct and informative as I can.
However, he's asked me about my BC pill and ovulation and how they all work and all that, and he's asked 3 times in three months... I'm not annoyed, and you shouldn't be either when he doesn't get it right away. We've been essentially trained in all this our whole lives and they are picking it up first with us. I know he's eager to learn and understand, and I know repetition is necessary for it to stick.
Try not to overwhelm him, and possibly bring up the more fun parts of amping up your ability to conceive first (like putting a pillow under your back during... it gets him deeper!) and repeat, repeat, repeat every time he asks! :)
I hope this helps!