Atypical hemolytic-uremic syndrome is associated with pregnancy or delivery in 12—31% of cases and can determine life expectancy in both mother and child. Objective — to analyze the clinical manifestations, course, and outcomes of atypical hemolytic-uremic syndrome in pregnant and puerperal women. Subject and methods. Twenty patients aged 19—38 years who had developed hemolytic-uremic syndrome during pregnancy or immediately after childbirth were followed up in 2012 to 2016. Results. The development of the above syndrome was mostly preceded by preeclampsia and/or HELLP syndrome and other obstetric complications, diarrhea. All the patients had a complete symptom complex of thrombotic microangiopathy: a significantly lower hemoglobin count (66±16.77 g/l) with signs of microangiopathic hemolysis (elevated LDH levels, 2953.16±3185.17 U/l, schizocytosis), thrombocytopenia (52.500±33.200 µ/l), acute kidney injury (hypercreatininemia, 466.3±212.4 µmol/l, oliguria or anuria). New-onset hypertension was noted in the majority of patients, i.e. 16/20 patients (80%). In all the patients, thrombotic microangiopathy was systemic: the signs of liver and lung diseases were present in 75% of the women (15/20), respectively; CNS lesion was observed in 70% (14/20), cardiac damage was seen in 40% (8/20). An analysis of the course of atypical hemolytic-uremic syndrome in relation to gestational age, the clinical and laboratory parameters at the time of disease development were more changed in women with the manifestations of the syndrome in the third trimester and postpartum. The treatment mainly encompassed plasma therapy as fresh-frozen plasma infusions and plasma exchange in 16/20 (80%) patients; treatment with eculizumab, a monoclonal antibody against complement component C5, was initiated in 8 patients. Maternal mortality was 35%. Conclusions. Pregnancy-associated atypical hemolytic-uremic syndrome is characterized by the development of multiorgan failure in the majority of patients. Syndrome development is preceded by various complement-activating states. Apparently, it is these pregnancy complications, rather than normal pregnancy itself, which are triggers of atypical hemolytic-uremic syndrome in women genetically predisposed to its development. The authors declare no conflicts of interest.