I don't know much about the two conditions you mentioned, though I was also on asprin because I have a genetic high risk for blood clots. My obgyn will tell you that going on the asprin was what saved my third pregnancy, but I don't believe it. I didn't take any with my fourth, and everything went fine. The obgyn didn't buy the hypothesis, but I'm inclined to agree with my allergist...My two miscarriages were becase of my asthema. He's had six patients that he knows of who all had very mild, untreated asthema and multiple misscarriages. As soon as we started treating the asthema, we all had successful pregnancies. His hypothesis is that the body dumps the pregnancy becase it isn't getting enough oxygen to support both the fetus and the mother. Makes a lot of sense, no?
Of course, it may be that none of this is your situation, but it can't hurt to check.
All the best.