The origin of increased serum iron in pregnancy-induced hypertension.

Serum iron was measured in 30 patients with pregnancy-induced hypertension and 24 normal pregnant women. The mean iron concentration was significantly higher in the group with pregnancy-induced hypertension (111 +/- 26 micrograms/ml) than in the controls (69 +/- 17 micrograms/ml) (p less than 0.0001). Readily available laboratory variables were used to determine whether the increased serum iron was the result of (1) hemolysis, (2) hepatocellular injury, or (3) intravascular volume contraction leading to hemoconcentration. It appears that a clinically silent, ongoing hemolytic reaction is responsible for the increase in serum iron seen in patients with pregnancy-induced hypertension.