Blood is classified by the presence of antigens from the ABO system or the rhD system. Around 85% of people are Rh Positive, meaning they have RhD antigen in their blood; while the remaining 15% are Rh Negative (they do not have antigen).
If a Rh Negative person comes into contact with Rh Positive blood, your body will recognize these antigens as foreign, and will create antibodies that destroy it (antibodies against the D antigen, AntiD)
During pregnancy or during the interruption, the blood of the pregnant woman and the fetus can mix. Then the blood of the woman in contact with the Rh Positive antigen, creates an antibody that attacks the fetus. If this occurs, the pregnant woman is sensitized and in future pregnancies can attack the fetal blood cells and generate hemolytic diseases or spontaneous abortions.
The AntiD Vaccine is composed of immunoglobulin that is given to Rh negative women to prevent sensitization. The antibodies will attack the fetal positive cells in the woman’s blood, preventing her from developing the antibodies.
It is important to remember that this same vaccine should be given to all women with Rh Negative in each pregnancy, also after performing invasive diagnostic tests (such as corial biopsy, amniocentesis, fetoscopies) or after an abortion.
To avoid problems in future pregnancies, it is essential to know the blood factor before an interruption, and know that Anti D must be administered within a maximum period of 72 hours.
In our pregnancy termination clinics, we apply a protocol according to which an analysis is made to our patients who do not know their blood factor; In case of Rh Negative the AntiD Vaccine is administered