Placental isoferritin: a new serum marker in toxemia of pregnancy.

The serum concentrations of placental isoferritin and normal ferritin were determined in 20 patients with preeclamptic toxemia of pregnancy and were compared with the level measured in normal pregnant women at the third trimester and in labor at term. The mean serum concentration of placental isoferritin for the women with preeclamptic toxemia was found to be low: 7.5 +/- 23 U/ml compared with 81.6 +/- 89.3 U/ml in normal pregnancy during the third trimester and 54.8 +/- 53 U/ml in term delivery. In comparison, there was no significant difference in the serum levels of normal ferritin in both pregnant women with toxemia and in those without toxemia. These results suggest that placental isoferritin may be a useful marker for preeclamptic toxemia of pregnancy.