When fetal RBCs (Rh+) leak into maternal circulation
Maternal development of Anti-Rh IgG antibodies
Cross placenta, hemolyze fetal Rh RBCs (erythroblastosis fetalis)
History / PE:
Previous SAB or TAB
Previous delivery w/o RhoGAM
Notes:
-RhoGAM coats the Rh+ fetal RBCs, preventing maternal anti Rh IgG development
-Give RhoGam at 28wks -Anti D (Rh) titers > 1:16, means maternal sensitization and anti D (Rh) production, follow closely for evidence of fetal hemolysis
