Antiphospholipid syndrome (APS or APLS) or antiphospholipid antibody syndrome is a disorder of coagulation that causes blood clots in both arteries and veins as well as pregnancy-related complications such as miscarriage, stillbirth, preterm delivery, or severe preeclampsia. The syndrome occurs due to the autoimmune production of antibodies against phospholipid (aPL), a cell membrane substance. In particular, the disease is characterised by antibodies against cardiolipin and β2 glycoprotein I. The term "primary antiphospholipid syndrome" is used when APS occurs in the absence of any other related disease...