The case study reported here concerned an intrauterine death as a result of a Kell erythroblastosis. Allergization had been caused by the administration of Kell-positive banked blood. Irregular antibodies are on the increase as a result of the increasing number of blood transfusions. It is recommended that the Kell system be considered in the selection of banked blood for girls and women of childbearing age--a practice that has been followed at the Innsbruck University Clinics for almost four years now. The indirect Coombs' test should be performed in order to establish Kell antibodies and other clinically significant antibodies. The enzyme test is recommended as a supplementary examination, but should never be used as the sole antibody test. As with rhesus incompatibility, and insofar as the determination of the father's Kell characteristics show him to be an antigen carrier, monitoring of allergized pregnant women must be carried out with the help of antibody titer follow-ups, amniocenteses, and ultrasonographic examinations at short notice.