Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 19-04: Prevention of Rhesus Alloimmunization + Key Features Download Section PDF Listen +++ ++ Anti-Rho(D) antibody causes severe hemolytic disease of the newborn Occurs when a Rho(D)-negative woman carries a Rho(D)-positive fetus and develops antibodies against Rho(D) The antibody developed against Rho(D) persists and poses a threat of hemolytic disease in subsequent Rho(D)-positive fetuses Passive immunization of Rho(D)-negative mothers after delivery destroys fetal Rho(D)-positive cells and prevents formation of antibodies, which would cause disease in subsequent Rho(D)-positive gestations + Clinical Findings Download Section PDF Listen +++ ++ Routine antibody screen is positive + Diagnosis Download Section PDF Listen +++ ++ Because hemolytic disease may occur in association with Rh subgroups or other red blood cell antigens, atypical antibodies should be assessed at 28 weeks in all pregnancies + Treatment Download Section PDF Listen +++ ++ Rho(D) immunoglobulin (Ig) is given to a Rho(D) negative mother within 72 h after delivery to prevent future erythroblastosis Additional protection is afforded by the routine administration of the Ig at week 28 to all Rho(D) negative mothers; the passive antibody titer is too low to harm the Rho(D)-positive fetus Rho(D) Ig should also be given after abortion, ectopic pregnancy, placental abruption, other antepartum bleeding Once a woman is alloimmunized, Rho(D) immune globulin is no longer helpful and should not be given