The project was undertaking by Peking University People's Hospital and other well-known hospitals in China. Aims at evaluating efficacy and safety of dexamethasone in management of ITP in pregnancy.

The investigators are undertaking a multicenter, open-labeled, pilot study of 50 ITP patients in pregnancy from Peking University People's Hospital and other well-known hospitals in China. ITP patients in pregnancy who failed to respond to prednisone, IVIG and developed refractoriness to platelet transfusion will be given dexamethasone intravenously at a dose of 40mg every day for four days. Platelet count, bleeding and other symptoms will be evaluated before and after treatment. Adverse events will be recorded throughout the study.

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.