Describe erythroblastosis foetalis.

When a Rh-negative mother is carrying a Rh-positive baby, there are chances that the child dies due to the interaction with the antibodies produced by the mother during the first child. The foetus will have the Rh antigens which will be considered as foreign invaders in mother's body. It can initiate the protective mechanism that can end up harming the child.

During the first pregnancy, the antibodies are produced in lower concentration and do not harm the foetus. But antibodies against the Rh factor will be produced in the mother’s body during delivery of the first child. During second pregnancy with Rh+ baby, the concentration of antibodies against Rh factor will build up and will attack the blood cells of the foetus and will cause its death. This phenomenon is referred as erythroblastosis foetalis.