What is the medical term meaning abnormal condition of red embryonic cells?

The correct answer is: erythroblastosis fetalis.

Erythroblastosis fetalis is a condition in which a pregnant woman's immune system attacks her fetus's red blood cells. This can happen when the mother and fetus have different blood types. The mother's immune system sees the fetus's red blood cells as foreign and attacks them. This can lead to anemia, jaundice, and other serious health problems in the fetus.