What are causes of recurrent abortion?

Varies. Many causes including a clotting disorder (antiphospholipid antibody syndrome that can be diagnosed with blood tests and might be associated with lupus), uncontrolled thyroid disease or diabetes, genetic, uterine (womb) abnormalities, and sometimes, the cause is not known. However, it requires an evaluation by a physician with experience in this area as some causes can be corrected and/or treated.