Thrombocytopenia in pregnancy.

The implications of thrombocytopenia in pregnancy vary with the etiology of the thrombocytopenia. This article focuses on defining what those etiologies are and assessing risk and therapy for each. Most important, the need to diagnose the largest and most benign entity of incidental thrombocytopenia is emphasized so that patients can be reassured and not subjected to further intervention. The angiopathic entities of preeclampsia, HELLP syndrome (hemolytic anemia, elevated liver function tests, and low platelets), disseminated intravascular coagulation, thrombotic thrombocytopenic purpura, and hemolytic-uremic syndrome may also cause severe thrombocytopenia. The controversy surrounding the particular therapeutic dilemma of immune thrombocytopenic purpura is explored, with evaluation of the actual danger to the mother, method of delivery, and treatment for the neonate. The serious nature of alloimmune thrombocytopenia is emphasized, and current modes of risk assessment and therapy are discussed.