Before proceeding with the case, let's review perinatal testing programs, also called 'Rh prevention programs' since they are designed to prevent HDFN due to anti-D.
Perinatal testing programs have two main purposes:
1. To detect, at an early stage in pregnancy, the presence of any IgG antibody that could cause HDFN in order to treat the infant as soon as possible.
2. To determine which women are candidates for RhIG in order to try to prevent the production of anti-D.
Testing programs include both Rh-negative and Rh-positive women, but because antibodies other than anti-D only rarely cause HDN, Rh negative females are tested more extensively.