BACKGROUND: Microangiopathic disorders during pregnancy remain a diagnostic challenge because these conditions often imitate more common obstetric diseases. CASE: A 31-year-old multigravid woman delivered at term with a postpartum course complicated by laboratory indices consistent with hemolysis, elevated liver enzymes, and low platelet count syndrome. After clinical recovery, she was readmitted 2 weeks after delivery with presumptive pyelonephritis. Persistent hemolysis and worsening thrombocytopenia suggested a diagnosis of thrombotic microangiopathy, which did not respond to plasma exchange. Directed bone biopsy revealed metastatic signet ring cell adenocarcinoma. CONCLUSION: Microangiopathic hemolytic anemia is rarely the initial clinical manifestation of malignancy. Given the similar features of several common obstetric complications, additional diagnostic measures may be necessary to refine the diagnosis in cases unresponsive to standard obstetric management.