anytime I deferred an SA appointment for my DH this month for exactly the same reason. They were very understanding. As for your two MCs - I hate to say this because it hurts to hear (I know!) - but your age is a factor ... so don't assume there's something drastically wrong with either of you.
I have also had two MCs, at the same age you were, and I was told that the one thing everyone tells 'older' women is that they might not get PG; what they don't say, is they will get PG but have a higher rate of MCs. Your eggs are not what they were.
Also MC at 6-8 weeks is the most common time to MC. And very early MCs (5 weeks) are very common for all women regardless of age - most women don't even know they've had one. A lot of foundation baby-making development happens very quickly in these early weeks. So baby will reach for the 'material' it needs from your egg, and if a small detail is missing or corrupt in the egg (more likely as you get older), the PG will fail.
This does NOT mean all your eggs are faulty: it means you've had bad luck twice in a row. Nothing more, nothing less.
I am not sure it is automatically on your DH's side. I've been told that usually only the fittest and best sperm make it to the egg in the first place (it's a marathon so they NEED to swim fast and well to get there). So if I were you I'd take huge heart from the fact you've managed to get PG twice already, and I wouldn't give up.
On the up side, statistically, (at least by the stats at the hospital I am at) you are at no hugely greater risk of another MC in your third PG than you were when you first got PG. This is why you usually don't get tested for 'reasons behind repeated MCs' until you've had three.
My consultant thinks if it happens for us a third time, that the next PG we'll be fine.