He's scared to test sperm!?!?

Katie • Implant out June `13. Ttc #3
It was nearly two and a half years ago since I had my implant removed. After 18 months I had my blood tested to see if I was still ovulating. All clear! Just last week I had my first internal scan. All clear!
About a year and a half into it I convinced my other half to have a sperm check. He reluctantly agreed but we made an appointment with the doctor. We had to wait 3 weeks just for a telephone appointment and he missed the call due to work so it was cancelled. He didn't attempt to make another appointment and I KNOW when not to nag and lose him to the man cave. Still not had it checked. 
Truth is I think he's scared to think he could be the reason I'm upset every month. 
He's 40 and thinks he's too old now. Our second child is now 9 and he thinks his days are done. But won't get confirmation. 
Now I have the all clear on my testing my doctor want to try clomid. And I'm keen to start too but it might be pointless. 
Can a mans sperm deteriorate that dramatically over a period of 10 years?
Are there ways of improving sperm numbers?
Anyone tried the sperm testing home kits and found them to be accurate?
I can't push him into going to the doctors but maybe if we try things at home to getting an answer to his fertility issue that we can try and improve than without the aid of a doctor.