Thrombocytopenia in pregnancy: etiology, differential diagnosis, management

Petkutė Simona 1, Prosevičiūtė Rūta 1, Rimdzevičiūtė Vytautė 1

1Lithuanian University of Health Sciences, Faculty of Medicine, Kaunas, Lithuania


Thrombocytopenia during pregnancy is diagnosed when platelet count drops below 150×10^9/L. The decline usually is not very significant and does not cause any damage to the mother or fetus. However, there are some conditions when to avoid serious consequences doctors must intervene. The aim of this article is to overview thrombocytopenia in pregnancy, its etiology, differential diagnosis and management. When lowered platelet count is detected, it is very important to identify a reason which can be both pregnancy specific and not related to pregnancy. The most common cause of thrombocytopenia during pregnancy, especially at the end of second and in the third trimester, is gestational thrombocytopenia which is diagnosed when all other causes are ruled out. Other pregnancy specific causes are preeclampsia, HELLP syndrome and acute fatty liver of pregnancy. Conditions that are not specific to pregnancy include idiopathic thrombocytopenic purpura, secondary immune thrombocytopenia, which may develop during  viral infections, autoimmune diseases or when antiphospholipid antibodies form as well as thrombotic microangiopathies, bone marrow pathology and various other factors such as malnutrition or administration of certain types of drugs. Main tools for the diagnosis of thrombocytopenia are complete blood count and peripheral blood smear when the amount, size and form of thrombocytes are thoroughly evaluated. For the differential diagnosis of thrombocytopenia it is important to assess the onset of it, blood clotting difficulties before the pregnancy and family history. It is also crucial to notice additional symptoms, such as hypertension, liver, kidney and central nervous system damage, proteinuria, pulmonary edema and elevated levels of certain enzymes and other biologically active substances. These symptoms and changes in blood samples can indicate life threatening conditions such as preeclampsia and HELLP syndrome, acute fatty liver of pregnancy, thrombotic thrombocytopenic purpura and atypical hemolytic uremic syndrome. There are no certain guidelines for treatment of thrombocytopenia in pregnancy and the amount of platelets needed for a successful delivery. Main drugs used to increase the concentration of thrombocytes are corticosteroids and intravenous immunoglobulin. Corticosteroids are usually the first choice and only if there is no effect or quick results are needed intravenous immunoglobulin should be administered. Thrombocytopenia is not the main factor when deciding the type of delivery, however, vaginal delivery is thought to be safer compared to C-section. Newborn thrombocytopenia is not uncommon but a severe decrease in platelet count (below 30×10^9/L) is rare and affects only 1-5% of newborns.


Keywords. Gestational thrombocytopenia, preeclampsia, HELLP syndrome, microangiopathies.