The cause of primary immune thrombocytopenia is not yet clear, but it is generally believed to be related to genetics, infection, estrogen, immune dysfunction diseases, etc. The specific cause of the disease needs to be confirmed after examination by a doctor. 1. Heredity: It is currently considered to be related to genetic factors, which needs to be confirmed by further research. 2. Infection: patients may have upper respiratory tract infections before the onset of primary immune thrombocytopenia, which are clinically considered to be highly related to infections, such as herpes virus and hepatitis virus. 3. Estrogen: primary immune thrombocytopenia mostly occurs in female patients, and the condition is more serious after pregnancy, which is clinically considered to be related to estrogen. 4. Diseases with immune function disorders: such as systemic lupus erythematosus, rheumatoid arthritis, etc., autoimmune combined platelet immune destruction may occur. If primary immune thrombocytopenia occurs, it is recommended to consult a doctor in time to clarify the cause of the disease and carry out targeted treatment or therapy with the help of a doctor.