What would you do?

Ok so my wife and I have been ttc #1 for 5 months now. We are using a known donor who comes to provide a few samples during my fertile week. I'm starting to get the feeling that he expected results by now and I don't want him to give up on us. So my question is how long would you try without results before maybe suggesting he take some male fertility supplements or something? Or should I ask him to be checked out? Because I've been to the dr and I have the green light. So.....is there maybe something wrong with his count or mobility? What would you do??