Nucleated Red Blood Cells Unit Converter

Nucleated red blood cells (NRBCs) are immature red blood cells that still contain a nucleus. They are also called erythroblasts or normoblasts.

In healthy adults, NRBCs are found only in the bone marrow, where red blood cells mature and expel their nucleus before being released into the bloodstream. The normal count in adult peripheral blood is zero.

NRBCs are normally present in the blood of fetuses and newborns, particularly premature infants, and typically disappear within the first few days to weeks of life. In adults and older children, the presence of NRBCs in circulating blood is considered abnormal and warrants further investigation.

NRBCs are produced in the bone marrow as part of normal red blood cell development (erythropoiesis). In certain pathological conditions, blood cell production may also occur in the liver or spleen through a process called extramedullary hematopoiesis.