An Rh+ fetus carried by an Rh- mother may have agglutination with in the blood.?

Question

How ever a fetus with B blood carried by a mother with A blood will not have agglutination. Based upon your knowledge of the immune system Explain why

Answer 1

http://en.wikipedia.org/wiki/Rhesus_bloo...

http://en.wikipedia.org/wiki/Agglutinati...

Answer 2

The problem with rhesus incompatibility only occurs when a rhesus negative mother has a second (or subsequent) rhesus positive baby.

Explanation :

a) The foetal and maternal blood flow comes close together at the placenta but the blood from both does not mix.

b) This does not cause a problem for a first rhesus positive pregnancy.

c) During delivery a small portion of the baby's blood may pass to the mother and her immune system would be sensitised and produce Anti D antibodies againt the 'foreign' cells.

d) During a second or subsequent rhesus positive pregnancy the Anti D antibodies can pass across the placenta to the foetus and agglutinates (clumps together) the foetal red blood cells.

e) In severe cases this leads to haemolytic disease of the newborn and the infant would require a blood transfusion after birth.

f) Rhesus negative mothers are given an injection after delivery of a rhesus positive child to destroy any antigens she has produced so that she doesn't react during another rhesus positive pregnancy.

The fact that the maternal an foetal blood supply does not mix means that a mother with blood group A can safely carry a foetus with blood type B.

Hope this helps!