The difference between lupus anticoagulant LA1 and LA2 mainly lies in that LA1 is the initial screening test for lupus anticoagulant, while LA2 is the confirmatory test for lupus anticoagulant, and it is the ratio of LA1 to LA2 that is relatively informative in clinical practice. Lupus anticoagulant belongs to a kind of antiphospholipid antibody, which is an autoantibody against negatively charged phospholipids in the human body. The reference range of LA1/LA2 is 0.8~1.2, and LA1/LA2 of 1.5~2.0 suggests that a moderate amount of lupus anticoagulant exists, while LA1/LA2 of more than 2 is a strong positive, suggesting that a large amount of lupus anticoagulant exists. The persistence of lupus anticoagulant is associated with factors such as habitual miscarriage, fetal growth retardation, stillbirth and other adverse pregnancies, autoimmune diseases and thrombotic diseases. Laboratory test results should be interpreted by a medical professional, and patients are advised to go to the Department of Rheumatology and Immunology, Department of Obstetrics and Gynecology, and other relevant departments in regular hospitals for detailed consultation.