What is another name for the medullary phase of hematopoiesis?

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The medullary phase is the bone marrow stage of hematopoiesis. During fetal development, hematopoiesis shifts from the yolk sac to the liver (hepatic phase), then to the spleen (splenic phase), and finally to the bone marrow—the myeloid phase. The term myeloid phase reflects that the bone marrow is the main site where the myeloid lineages—erythrocytes, megakaryocytes, granulocytes, and monocytes/macrophages—are produced. So the medullary phase is best named the myeloid phase. The other options correspond to earlier sites: yolk sac for primitive hematopoiesis, hepatic phase for the liver, and splenic phase for the spleen.