Growth factor activity in the blood of women in whom preeclampsia develops is elevated from early pregnancy.

Preeclampsia is a pregnancy-specific disorder of uncertain cause and pathophysiology that appears to be associated with endothelial cell injury. Our current studies demonstrate that a pregnancy growth factor activity is elevated compared with postpartum values in the blood of women with preeclampsia months before the onset of clinical manifestations of toxemia. A cohort of primigravid women was followed throughout pregnancy and multiple serial plasma samples from six women with preeclampsia and six matched normal women were assayed for mitogenic activity. The data indicated that the ratio of predelivery/postdelivery plasma mitogenic activity was greater in women predestined to meet strict criteria for the diagnosis of preeclampsia compared with matched normal primigravid women. Growth factor activity could distinguish women in whom preeclampsia would develop from their normal peers throughout pregnancy, and as early as the first trimester of gestation (p less than 0.05). Similar studies performed with plasma obtained greater than 6 weeks post partum, when the two groups of patients were clinically indistinguishable, revealed no differences in this index of mitogenic activity. Our results indicate that elevated mitogenic activity ratios of prepartum versus postpartum plasma antedate the clinical recognition of preeclampsia, and return to normal with the resolution of the syndrome.