The frequency of hemolytic disease of the newborn due to maternal antibodies of subgroup incompatibility other than anti-D (Rh) antibodies has increased in recent years after the common use of anti-D (Rh) immunoglobulins in Rh incompatibilitiy. In this article a newborn who was hospitalized because of jaundice and diagnosed to have E minor blood group incompatibility is presented, and it is emphasized that the underlying etiologic factor may be subgroup incompatibility rather than Rh incompatibility in cases with seemingly Rh-Rh incompatibility who have mild jaundice and a positive direct Coombs test.

Keywords: newborn, anti-E, subgroup incompatibility, hyperbilirubinemia