Who is at risk for Rh incompatibility

When you first go to meet your gynecologist, she/he will usually ask you to take a blood test to determine your blood type.  People with no Rh factor in their blood are called Rh negative.  If you are Rh positive (85% are), or if both you and the father are Rh negative, then there is no issue.  However, if you are Rh negative (Rh-) and your partner is Rh+, and if this is your second pregnancy (or later), preventive measures are not taken. Else,  the baby may contract the Rh disease, and the baby's health may be at risk.
 

What is Rh disease

In a situation where Rh incompatibility exists, Rh disease occurs when the Rh factor enters the Rh negative's mothers circulatory system during the delivery of a baby who has inherited the Rh factor from his or her father. The mother's immune system reacts by producing antibodies to act against the "foreign" substance. These antibodies have no effect in a first pregnancy. If the woman gets pregnant again with a Rh positive baby, the antibodies cross the placenta and attack the foetal red blood cells which could lead to anaemia in the baby. 
 

How can Rh disease be prevented

A dose of vaccine can control the incidence of Rh disease. At 28 weeks, an expectant Rh negative woman showing no antibodies in her blood is given a dose of Rh-immune globulin. She is given another dose 72 hours after delivery if the baby is Rh positive. If the levels of antibodies are very high in the mother's blood, endangering the life of the foetus, a transfusion of Rh negative blood in the foetus may become necessary.