Question

In which of the following situations, is there a risk factor for children of incurring Erythroblastosis foetalis?

• A. Mother is Rh $- ve$ and father is $Rh +ve$
• B. Mother is Rh $- ve$ and father is $Rh -ve$
• C. Mother is Rh $+ve$ and father is $Rh -ve$
• D. Mother is Rh $+ve$ and father is $Rh +ve$

Answer 1

Answer: (A)

Mother is Rh $- ve$ and father is $Rh +ve$

Answer 2

The Rh-factor has great significance in child birth. An Rh- negative woman married with Rh-positive man becomes sensitised by carrying a Rh-positive child within her body.

This is because an Rh-vc person, if exposed to Rh+ve blood, will fonn specific antibodies against the Rh antigens. This is observed in case of Rh-vc blood of a pregnant mother with Rh+ve blood of the foetus. Rh antigens of the foetus do not get exposed to the Rh-ve blood of the mother in the first pregnancy as the two bloods are well separated by placenta. However, during the delivery of the first child, there is a possibility of exposure of the maternal blood to small amounts of the Rh+ve blood from the foetus. In such cases, the mother starts preparing antibodies against Rh antigen in her blood. In case of her subsequent pregnancies, the Rh antibodies from the mother (Rh-ve) can leak into the blood of the foetus (Rh+ve) and destroy the foetal RBCs. This could be fatal to the foetus or could cause severe anaemia and jaundice to the baby. This condition is called erythroblastosis foetalis.