A nurse on the postpartum unit is preparing to administer Rh-immune globulin (RhoGAM). The nurse should recognize that this medication is indicated for which of these clients?

• A. Rh-neg mother with an Rh-neg infant
• B. Rh-neg mother with an Rh-pos infant
• C. Rh-pos mother with an Rh-pos infant
• D. Rh-pos mother with an Rh-neg infant

Answer: (B)

RhoGAM works to prevent the mother’s immune system from becoming sensitized to the Rh antigen after exposure to Rh-positive fetal cells. It’s given to an Rh-negative mother after delivery of an Rh-positive infant to stop the formation of anti-D antibodies that could affect future pregnancies. The administered anti-D antibodies bind to any Rh-positive fetal red cells in the maternal circulation, masking the D antigen and allowing them to be cleared before the mother’s immune system can mount a response. This postpartum protection is specifically indicated when the mother is Rh-negative and the newborn is Rh-positive. It isn’t needed for an Rh-negative mother with an Rh-negative infant, and it isn’t used in Rh-positive mothers, since they already express the D antigen and aren’t at risk for sensitization in the same way.