We read with interest the recent report by Garner et al. [l], in which anti-E was detected early in pregnancy solely through the use of enzymetreated red blood cells (RBC). The serological reactivity of this anti-E changed dramatically during pregnancy; the antibody became detectable by the indirect antiglobulin test, and at 37 weeks’ gestation had a titer of 512. Delivery at 40 weeks’ gestation yielded an infant affected with hemolytic disease of the newborn (HDN) requiring exchange transfusion and 4 days of phototherapy. This case was further complicated by antiK1, stimulated by prior transfusions, that was present throughout the pregnancy but did not contribute to the HDN, and an anti-c that was detected solely in tests with enzyme-treated RBCs at 35 weeks’ gestation, but was not demonstrable in the infant at delivery. While we concur with the authors that there is a need to screen both Rh D-positive and Rh D-negative women for RBC alloantibodies early in pregnancy, and while we agree that once an antibody has been detected it should be identified and evaluated for its potential to cause HDN, we Appropriate Serological Testing in Pregnancy