{Reference Type}: Case Reports {Title}: Pregnancy-associated atypical hemolytic uremic syndrome. Case report. {Author}: Barrera-Hoffmann C;Mariaca-Ortíz Y;Ruiz-Villa JG;Cuevas-Cruz LE;López-Mendoza MDR;Briones-Garduño JC; {Journal}: J Obstet Gynaecol Res {Volume}: 50 {Issue}: 7 {Year}: 2024 Jul 9 {Factor}: 1.697 {DOI}: 10.1111/jog.15958 {Abstract}: Pregnancy-associated atypical hemolytic uremic syndrome (P-aHUS) is a rare disease. There are only few reports in the literature, and most are in the puerperium period. It is a thrombotic microangiopathy (TMA) characterized for microangiopathic hemolytic anemia, thrombocytopenia, and renal dysfunction. We report the case of a pregnant patient at 26.3 gestation weeks, who developed clinical features of TMA, neurological alterations, and septic shock; then after fetus and placental delivery, no clinical improvement was observed; a diagnostic protocol was performed due to suspicion of P-aHUS, showing improvement after the plasma exchange sessions and eculizumab. We present here a brief review of the case since it is an entity that needs to be suspected during pregnancy when TMA features and requires an immediate diagnosis to provide timely treatment.