rhesus factor disease

rhesus factor disease

A severe blood disorder caused by incompatibility between the blood group of the fetus and that of the mother. The rhesus factor is acquired by dominant inheritance and is present is 85% of the population. The danger arises if the mother is rhesus negative and the father rhesus positive and passes this on to the fetus. When the fetus is rhesus positive, its red blood cells act as ANTIGENS causing the mother to produce ANTIBODIES against them. The danger is minimal in the first pregnancy but increases thereafter as antibody levels rise. In the most severe cases, the fetus may die in the womb. If born alive, the baby is deeply jaundiced with an enlarged liver and spleen and a low haemoglobin level. Treatment is by an exchange transfusion, via the UMBILICAL CORD, immediately after birth or even while still in the womb. Rhesus negative women can be prevented from developing antibodies by being given an anti-D GAMMAGLOBULIN.