What does it mean when you have to get the rhogam shot while pregnant? my blood type is a- &' my obgyn said i had to get it. is there something wrong

Prevent Antibodies: "a negative" means that your body hasn't been exposed to a factor called "rh." your baby could have that factor though and if so, your body will think of that factor as foreign and create antibodies that will attack your next pregnancy if it also has that factor. Rhogam prevents these antibodies from forming by binding to the factor, hiding them, and ensuring your body doesn't create antibodies.