Jo,
I am so sorry you are going throught this again. My heart goes out to you.
I am always hesitant at replying to messages because we were blessed with Olivia and Sophia. But Olivia wasn't until after a long time, and not until I was 38, and Sophia at 40. However, to the point of your question, I did every test under the sun, including extensive genetic testing. (Ah, the elusive undiagnosed infertility of advanced maternal age

)
All it required from me and DH was blood. They tested for abnormalites, markers, things pertaining to our heritage, (he's Portugese and I'm Itallian) and things that ran in our families like diabetes.
It took forever to get back the results, well, 2 weeks I think, but that's pretty close to forever. They never found anything, and because we concieved Sophia a year after Olivia was born we didn't have to test again.
We are going to try for a third miracle, and we will have to test again this time. (because now, I'm really old

)
It can't hurt, sometimes it gives them more information to work with, and it should never deter you. It only empowers you with more information, and still allows you to make your choices.
I wish you all the best, whether you continue on this rollercoaster, or begin a new journey with adoption.
Good luck with your eliptical. I love mine, DH gave me one for Christmas a few years ago, and it still kicks my but!!!