Pregnant women who present with new-onset hypertension will normally have a routine CBC performed to assess hemoglobin, hematocrit, and platelets. A peripheral blood smear analysis is also performed to look for the presence fragmented red cells, such as schistocytes (top image on the right) or the presence of echinocytes (burr cells) (bottom image). The CBC and peripheral smear analysis can be used to help identify the presence of severe preeclampsia and to identify any hemolysis, which may occur in the HELLP syndrome.
Platelet count, prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, and/or D-dimer tests may be performed to identify coagulopathy or coagulation-related problems as may develop in severe preeclampsia and in the HELLP syndrome. Decreased platelet count and decreased fibrinogen level combined with elevated PT and/or aPTT and increased D-dimer level are associated with the HELLP syndrome.