What do you make of this? (sorry this is long)

I am 37 and this is my first pregnancy. I have had late periods before and then very heavy bleeding when it did show up. Some of these times I thought it possible I was pregnant. I have never had a confirmed miscarriage. I also have had numbness in hands and feet for past several years that my neurologist could not find a reason for. My OB is aware of all of this (he has been my doc all along) . I got my BFP on May 9th (period was due on the 14th) I went in on may 13th for blood draw to check hcg & progesterone. Hcg was 82/progesterone 24.4. My hcg has been consistantly going up but progesterone dropped to 16.6 then to 10.6 this week. Yesterday when the nurse called with results they started me on Crinone and scheduled an ultrasond for tomorrow. My original appontment for first exam and u/s was June 27th. The nurse called me again today and said due to my age and to increase circulation to the baby my doctor wants me to start taking baby aspirin daily. She also mentioned it is to avoid small blood clots. I have been concerned about antiphospholipid antibody syndrome but no one has wanted to test me for it. What I am wondering is do doctors routinely put women on aspirin in the first trimester for any other reason than a clotting disorder being suspected?