Obstetric and Gynecological Nursing - The Carter Center

The first encounter may not result in actual antibody formation
but the woman will be sensetised; on a second encounter,
antibodies are produced in abundance. Once formed, these
antibodies are permanent.
Other occasions on which a fetomaternal transfusion may
occur are at abortion, amniocentesis, external cephalic
version or ante partum haemorrhage.
Prevention of maternal iso-immunisation
There are three ways of preventing a woman from producing
Rhesus antibodies:
- avoiding transfusion of Rh positive blood
- prevention of avoidable fetomaternal transfusion
- administration of anti- D immunoglobulin
Avoiding transfusion of Rh positive blood
Even if a small amount of Rh positive blood introduced in to
the circulation of a Rh negative person will result in
sensitization. Rh positive blood should never be administered
if the individual’s blood group is unknown and whenever
possible cross matching should be undertaken prior to blood
transfusion.
Administration of anti-D immunoglobulin
This will coat the fetal red cells that contain Ag and destroy
them before the woman’s immune system has time to
recognize the foreign protein and react to it. The
163