Thrombotic microangiopathies (TMAs) are severe endotheliopathies that can arise in pregnancy and require early recognition. Complement-mediated (C-)TMA should be differentiated from other endotheliopathies of pregnancy, as treatment differs. Here, we report on a case of a pregnant woman with acute kidney injury requiring hemodialysis due to C-TMA on the background of a pathogenic C3 variant at 28+5 weeks of gestation. Low soluble Fms-like tyrosine kinase-1 to placental growth factor (sFlt1/PlGF) ratio excluded preeclampsia.