How I treat thrombocytopenia in pregnancy

Thrombocytopenia is a common hematologic abnormality in pregnancy, encountered in about 10% of pregnancies. There are many possible causes, ranging from benign conditions that do not require intervention to life-threatening disorders necessitating urgent recognition and treatment. While thrombocytopenia may be an inherited condition or predate pregnancy, most commonly it will be a new diagnosis. Identifying the responsible mechanism and predicting its course is made challenging by the tremendous overlap of clinical features and laboratory data between normal pregnancy and the many potential causes of thrombocytopenia. Multidisciplinary collaboration between hematology, obstetrics and anesthesia and shared decision making with the involved patient is encouraged to enhance diagnostic clarity and develop an optimized treatment regimen, with careful consideration of management for labor and delivery and the potential fetal impact of maternal thrombocytopenia and any proposed therapeutic intervention. In this review, we outline a diagnostic approach to the pregnant patient with thrombocytopenia, highlighting the subtle differences in presentation, physical exam, clinical course and laboratory abnormalities that can be applied to focus the differential. Four clinical scenarios are presented to highlight the pathophysiology and treatment of the most common causes of thrombocytopenia in pregnancy: gestational thrombocytopenia (GT), preeclampsia and immune thrombocytopenia purpura (ITP).