[Serum unconjugated 2-hydroxyestrone and erythrocyte catechol-O-methyltransferase activity in pregnancy toxemia]

To clarify the significance of catecholestrogens in toxemia of pregnancy, plasma unconjugated 2-hydroxyestrone (2-OHE1) was measured by a specific radioimmunoassay. In addition, catechol-O-methyltransferase (COMT) activity in erythrocytes was compared between normal and toxemic pregnancies. The following results were obtained. There was no significant difference in the plasma 2-OHE1 level between normal and toxemic pregnancies in the 3rd trimester, these being 220 +/- 53(SD,n = 7), 162 +/- 138(n = 9) pg/ml, respectively. However, the plasma 2-OHE1, level was quite low in all three subjects in toxemic pregnancy with placental dysfunctions. Liver dysfunction was found in only one case of toxemic pregnancy, whose plasma 2-OHE1 was within the normal range. In two cases of mild toxemia and one case of severe toxemia with placental dysfunctions there was no significant difference in COMT activity as compared with normal pregnancy. The COMT activity of a diabetic woman with pregnancy toxemia without placental dysfunctions was slightly higher than that of a normal pregnant woman. From these results it is suggested that the lower plasma 2-OHE1 level in toxemic pregnancy may be caused by placental dysfunctions.