Recommendations of the AGG (Obstetrics and Prenatal Medicine Working Group, Section Maternal Diseases) on Maternal Thrombocytopenia in Pregnancy.

Thrombocytopenia is a common hematologic disorder characterized by reduced platelet count in peripheral blood. Acquired and chronic thrombocytopenia is very important in obstetrics. A decreased platelet count of 15-20% is normal in uncomplicated pregnancies; platelet count decreases continuously from 1st trimester on, however usually remains within the normal ranges of between 150 and 450 G/L. The occurrence of mild thrombocytopenia (100-149 G/L) in pregnancy is usually due to gestational thrombocytopenia and does not require further evaluation. But a differential diagnostic examination should be carried out if the platelet count drops to < 100 G/L. Other forms of thrombocytopenia may also occur or become activated in pregnancy and they require special attention. This recommendation presents the diagnostic workup, differential diagnoses, and possible consequences of different thrombocytopenia conditions in pregnancy. The recommendations are based on current international recommendations (George 2023, Bussel 2023) and a search of the literature using the search terms "thrombocytopenia" and "pregnancy".