Rh Immune Globulin (Rhogam, RhIG)
• Indicated if mother is Rh negative and has no Rh antibodies
• Given at 28 weeks or whenever there is possibility of feto-maternal hemorrhage (e.g. spontaneous abortion, termination, ectopic, CVS/amniocentesis, antepartum hemorrhage, postpartum)
• Protection lasts approximately 12 weeks
• During this time, patient’s antibody screen will be positive
• Consider testing the father: if father Rh negative as well then baby must be Rh negative and Rhogam will not be required
• Ensure patient understands the potential severity of alloimmunization. She must be certain as to paternity if declining RhIG - if in doubt, give anyway
• Rhogam is an IgG antibody, which prevents mother from mounting an immune response to any Rh positive fetal red blood cells in the maternal circulation during pregnancy
• Dose is 300 mcg given intramuscularly at 28 weeks’ gestation: standard dose is sufficient to protect against ~25 mls of fetal blood
• Do Betke-Kleihauer test and adjust dose if suspect larger feto-maternal hemorrhage
• The blood group and antibody screen (G&S) ordered at the first antenatal visit will identify if mother already has Rh antibodies - Rhogam not given to patients already alloimmunized