One of the problems with infertility is the blaming that begins to happen. Not only do the partners blame each other, but so do the mothers-in-law (it's not "my" child's fault!) and other interested onlookers. I'd try to avoid that trap. Did he point the finger at you when you miscarried and imply you did something wrong or have a less than perfect uterus? I doubt it.
If you keep trying for a year altogether, i.e., until this upcoming December, and nothing happens, go see a fertility specialist together. He or she will doubtless have a standard regime of tests that he runs you both through, and it's so cut and dried that your husband will not think he is being singled out as the problem. In the meantime, stop brooding that it is him. His record suggests that it is not. Turning 40 has nothing to do with it, for men. (My husband was a lot older than that when he had his first child.)
ps -- I hope your husband doesn't smoke around the kids. It's especially bad to have ciggie residue on your clothing when you hold a baby ... has been implicated in SIDS.
The easiest way to rule out it being him (or finding out if it is him) is to go to a urologist and give them a sperm sample to test. If it's not him then you may be the reason you aren't conceiving. That's when they'll test you to see if there are any problems.
Your TTC story is sort of the opposite of me. My first baby took 8 months of TTC and we finally succeeded all by ourselves! We did get desperate, so DH actually did the semen analysis 4 days before I got my BFP! I called the doctor and they thought I was calling for his results when I was calling to tell them I was pregnant. We didn't even try with baby number 2! She was an early surprise - due in 12 days! I guess my point is, even if it didn't take you long before, it might take you longer for this one and nothing could be wrong. I think waiting the full year before medical intervention and trying on your own is still a good bet. I don't think age affects men so early like it does women with fertility.
OH!! It's not a "blame" thing AT ALL! Didn't mean to come off that way. Just trying to figure out what's up, that's all. (And no, he doesn't smoke around the kids--- outside only! )
I know it's probably nothing-- there's plenty of women who take a few months or even a year or more to conceive and nothing's wrong. It's just so hard to be patient... :( Aaghh!
Our 1st wasnt "planned". When we started to try for baby #2 we got pregnant that 1st month but ened in a D&C as well. After that I got pregnant 2months later. But With our 3rd, it took us about 6months. I dont know why...I think its god why of saying maybe its not the right time? Idk. Hang in there, it will happened soon. We all know you can get pregnant, Hehe :) Im sure your hubby swimmer are find....Good Luck