Thrombocytopenia in Gestational Period

Inclusion Criteria: * Subject is between 20-50 years old. * After 12 weeks gestation. * Diagnosed with ITP meeting the diagnostic criteria for immune thrombocytopenia. * Patients who have no response or relapsed after Corticosteroid or IVIG. * Patients developed refractoriness to platelet transfusion. * To show a platelet count \< 30×10\^9/L, and with bleeding manifestations. * Willing and able to sign written informed consent. Exclusion Criteria: * Received chemotherapy or anticoagulants or other drugs affecting the platelet counts within 3 months before the screening visit. * Received second-line ITP-specific treatments (eg, cyclophosphamide, 6-mercaptopurine, vincristine, vinblastine, etc) within 3 months before the screening visit. * Current HIV infection or hepatitis B virus or hepatitis C virus infections. * Severe medical condition (lung, hepatic or renal disorder) other than chronic ITP. * Unstable or uncontrolled disease or condition related to or impacting cardiac function (e.g., unstable angina, congestive heart failure, uncontrolled hypertension or cardiac arrhythmia). * Have a known diagnosis of other autoimmune diseases, established in the medical history and laboratory findings with positive results for the determination of antinuclear antibodies, anti-cardiolipin antibodies, lupus anticoagulant or direct Coombs test. * Patients who are deemed unsuitable for the study by the investigator.