Causes of Haemolytic Disease of the Newborn
Haemolytic disease of the newborn (HDN) is a condition that occurs when the mother and fetus have different blood types. It is caused by the mother's antibodies attacking the baby's red blood cells. In the western world, the most common cause of HDN is the Rh factor.
The Rh factor is a protein found on the surface of red blood cells. Rh-negative mothers carry antibodies to Rh-positive blood, which can attack the baby's red blood cells during pregnancy or delivery. The Rh factor is inherited, and if both parents are Rh-negative, the baby will also be Rh-negative and will not be at risk of HDN. However, if one parent is Rh-positive, and the other is Rh-negative, the baby is at risk of developing HDN.
Prevention of HDN
The most effective way to prevent HDN is to give the mother an injection of an antibody called RhIgG. This injection is given at 28 weeks of pregnancy and again after birth if the baby is Rh-positive. This injection stops the mother's body from producing antibodies to Rh-positive blood, so the baby is protected from HDN.
Treatment of HDN
If a baby is born with HDN, they will need to be treated with a blood transfusion. This will replace the baby's destroyed red blood cells and stop them from becoming anaemic. In some cases, a baby with HDN may also need to be given medication or phototherapy.
In summary, the most common cause of HDN in the Western world is the Rh factor. It is important for pregnant women to be tested for the Rh factor so they can receive the correct treatment if necessary. Prevention and early treatment of HDN is key in ensuring the health and safety of the baby.
