Question

Marriage between one of the following pairs may cause child death

• A. $ Rh^{+} $ father and $ Rh^{-} $ mother
• B. $ Kh^{+} $ father and $ Rh^{+} $ mother
• C. $ Rh^{-} $ father and $ Rh^{-} $ mother
• D. $ Rh^{-} $ father and $ Rh^{+} $ mother

Answer 1

Answer: (A)

Marriage between $Rh^+$ man and $Rh^-$ woman, sometimes may cause into $Rh$ factor incompatability. If the blood of the foetus is Riband that of the mother is $Rh$. $Rh$ factor, antibody is formed in mother's blood. Hence, when mother's blood circulates in the foetus, it causes clumping of the RBCs of foetus and this is erythroblastosis foetalis. In this first pregnancy is safe, because of the concentration of $Rh$ factor antibody in mother's blood is negligible but the second child dies either in the foetus or just after birth.