What is the likelihood that is is not me?

Ok, I'll try to make a long story short.  DH and I have 4 kids and i've also had 3 m/c.  Most recently in Dec @ 12 wks which required a d&c (my first).  Since then, we have been unable to conceive, although we  started trying immediately.  It has been 6 cycles since my d&c.

I know it sounds crazy, but FIVE of my 7 pregnancies were conceived on the first first try; literally!  (The other 2 were unplanned.)  So while 6 months doesn't sounds like a long time, it is concerning to me.

Here's what I'm starting to wonder.. COuld it be DH's issue  (a sperm issue) and not mine?? All of my kids are with him.  He also has a daughter from a previous relationship, so he is obviously quite fertile, LoL.  BUT-- he does smoke, drink (not heavily) and he just turned 40 this month.  (I am 32.)

What do you think?  I really really hope it is not sperm-related, as I don't think he would be willing to DO anything about it (i,e, get tested for sperm motility, go through iui (if necessary), etc).  But I am desperate for baby #5. :( Any ideas?

[Tryingforbaby2]

I have issues with endometriosis and not ovulating regularly so we always knew the problem getting preg was me. Then when finally referred to the RE my dh had to get tested. Turns out we were fighting some major odds there as well. His count was low and morphology was low. He had to completely stop drinking alcohol, caffiene, and took fertilaid and we did IUI with success. I know that any of that stuff including smoking and not eating right can definitely cause low sperm count and morphology so definitely worth looking into. The testing is simple and don't necessarily need to do IUI. Good luck :)