The paper describes a clinical case of the diagnosis and treatment of fetal and neonatal hemolytic disease. Intrauterine transfusion of packed red blood cells and exchange blood transfusion in a baby resulted in a clinically significant increase in the level of hemoglobin and red blood cells. The absence of marked anemia, a major factor stimulating erythropoiesis, permitted long-term bone marrow hypofunction in an infant. The therapy performed in that period was aimed at lowering the concentration of total bilirubin and the neonatal blood levels of maternal antibodies, at enhancing the body’s excretion of bilirubin, and at reducing its toxicity. Adequate erythropoiesis occurred by 3 months of life when anti-rhesus antibodies were at the level unable to cause massive erythrocyte hemolysis and to affect the baby’s health. The authors declare no conflicts of interest.