Biochemical evidence of impaired trophoblastic invasion of decidual stroma in women destined to have preeclampsia

OBJECTIVE: Reduced trophoblastic migration into the decidua during the first half of pregnancy is a fundamental abnormality in preeclampsia. CA 125 and insulin-like growth factor binding protein-1 are major endometrial proteins whose primary sources are decidual epithelial and stromal cells, respectively. We hypothesized that reduced trophoblastic invasion in pregnancies destined for preeclampsia would affect the maternal vascular deportation of these decidual proteins. STUDY DESIGN: CA 125 and insulin-like growth factor binding protein-1 concentrations were analyzed by radioimmunoassays of plasma from preeclamptic and matched control patients in a longitudinal, nested case-control study. RESULTS: CA 125 concentrations did not differ with respect to pregnancy outcome or trimester. Midtrimester plasma insulin-like growth factor binding protein-1 concentrations were significantly lower in women who later had preeclampsia compared with normal pregnant controls. CONCLUSION: These findings provide biochemical evidence that abnormalities of trophoblastic invasion affect the maternal vascular deportation of a decidual stromal protein. Lower circulating concentrations of insulin-like growth factor binding protein-1 in women destined to have preeclampsia were observed 12 to 26 weeks before the onset of clinical signs of this syndrome.