What is true of fetal hematopoiesis in the course of pregnancy?
Fetal hematopoiesis: yolk sac - fetal liver - fetal bone marrow. The first fetal erythrocytes are nucleated and macrocytic. MCV is 180 fL and normally decreases to 105 to 115 fL. As the fetus grows, the blood volume in fetoplacental circulation increases. The fetalhemoglobin concentration increases from 12 gm/dL in mid pregnancy to 18 gm/dL at term. The retic count decreases to about 4 to 5 % at term. The RBC life span increases to 90 days at term.
Rise in MCV
Rise in reticulocyte count
Rise in Hemoglobin content
Decrease in blood volume
Fetal circulation