Question

The condition of erythroblastosis foetalis occurs only when

• A. the husband is $Rh^+$ and wife is $Rh^-$
• B. the mother is $Rh^-$ and the foetus is $Rh^+$
• C. the mother is $Rh^+$ and the foetus is $Rh^-$
• D. the husband is $Rh^ -$ and wife is $Rh^+$

Answer 1

Answer: (B)

the mother is $Rh^-$ and the foetus is $Rh^+$

Answer 2

When the mother is $Rh ^{-}$ and the foetus is having $Rh ^{+}$, the immune cells of the mother will produce the antibodies against the blood cells of the foetus.
This will lead to destruction of the blood cells in the foetus when the antibodies migrate through the placenta and enter the foetal system. This causes the death of the foetus and the condition is known as erythroblastosis foetalis.