In the United Kingdom, where selenium dietary intake is low, our group and others have reported selenium concentrations in preeclamptic pregnancies to be reduced in sera from the mother and fetus as well as in amniotic fluid and in toenails100when compared with normal pregnant controls. Conversely, others have shown no differences, and in 1 study from the United States, higher sera selenium concentrations have been reported in women with preeclampsia. However, a reported lack of sensitivity of the assays used, or dependence of the maternal leucocyte selenium content in estimation of selenium status, may con-found the interpretation of these studies