Figure 1.

Heparin administration increases plasma sFLT1 and unbound PGF and decreases unbound VEGF in nonpregnant women. Plasma sFLT1 (A), unbound PGF (B), and unbound VEGF (C) concentrations before and after heparin in nulligravid women and women with a prior uncomplicated pregnancy or prior preeclampsia. Lines show pre- and post-heparin concentrations for individual subjects. Large circles show the group median. Median sFLT1 concentrations at baseline were 30 pg/mL in nulligravid women, 34 pg/mL in women with a previous uncomplicated pregnancy, and 42 pg/mL in women with prior preeclampsia (Supplemental Figure 1). After the heparin bolus, median sFLT1 concentrations increased to 9032 pg/mL in nulligravid women, 10 003 pg/mL in women with a previous uncomplicated pregnancy, and 11 424 pg/mL in women with prior preeclampsia. *, Significant increases in sFLT1 and PGF and significant decreases in VEGF after heparin administration in all subject groups (P < .001 for all).