Darn pregnancy brain, totally forgot to come back here and post!
Anyway, you might want to try prostate stimulation with your DH if he's willing to try it. The less intensive way is to press on the space just behind the scrotum in the perineum area. This will put pressure on the prostate which is their G spot. I started out learning this when DH wanted to...manually pleasure himself with my help (usually when I'm on AF as I'm not one who likes sex during AF). You start out lightly and then press firmer. You will know when you hit the right spot. Sometimes you need to press slightly towards the base of the scrotum a little to get the right spot.
If your DH is more adventurous, the Aneros anal toy is excellent. He would put it in during foreplay and keep it in during sex, which would work better for TTC purposes. It's guaranteed to give him lots of pleasure and a good O. They have lots of models, but the basic one is fine. My DH has a few different ones including the original Aneros and the Vice (then again, my DH is bisexual and quite open to anything in the bedroom). The website I linked above has lots of information, so check it out.
Feel free to PM me if you have any other questions!