Christina,
I know I was told what my children's blood type was but I can't remember my son's, it is not something I worry about. But I do remember my daughter's because she has a poor medical history. I didn't know what my blood type I was until I donated, and I don't thinks many JW's know their blood type.
As far as him going for blood tests, they don't test what type of blood you are unless there is a reason for it. Most tests are just for targetted areas, such as cell counts, and cholestrol, etc. Normally unless going in for serious surgery, many people in general don't have any idea what blood type they are.
One, other thing Work out your probs with him, before the kiddies come along. I think feeling like a pin cushion might be the least of your worries, if things are not a bit smoother between you too.
wendy
Blind faith can justify anything.~Richard Dawkins