In an RhD negative mother, RhIG can prevent temporary sensitization of the maternal immune system to RhD antigens, which can cause rhesus disease in the current or in subsequent pregnancies. With the widespread use of RhIG, Rh disease of the fetus and newborn has almost disappeared in the developed world. The risk that an RhD negative mother can be alloimmunized by a RhD positive fetus can be reduced from approximately 16% to less than 0.1% by the appropriate administration of RhIG.