Yes, the reason aspirin is usually recommended is to thin the blood. So called thick blood syndrome can cause repeated miscarriages. I have just been diagnosed with what is called Hughes syndrome, thick boold syndrome. My ob gyn just recommend to take aspirin but did not order any blood tests, while I decided to do tests anyway first with an endocynologist. I have had 3 miscarriages in the past 12 months and I thought it was a bout time I had proper tests. I have been in generally good health otherwise, and unless I had those tests I would not have had a faintest idea why. Now at least I will have some better knowdlege and can deal with the probelm.
Good luck
Ania