Table 1 The diagnostic criteria and classification of HELLP syndrome [7]

Class 1: requires severe thrombocytopenia (platelets ≤50,000/μl), evidence of hepatic dysfunction (AST [aspartate aminotransferase] and/or ALT [alanine aminotransferase] ≥70 IU/l), and evidence suggestive of hemolysis (total serum LDH [lactate dehydrogenase] ≥600 IU/l).

Class 2: requires similar criteria except thrombocytopenia is moderate (>50,000 to ≤100,000/μl).

Class 3: includes patients with mild thrombocytopenia (platelets >100,000 but ≤150,000/μl), mild hepatic dysfunction (AST and/or ALT ≥40 IU/l), and hemolysis (total serum LDH ≥600 IU/L).