Plasma factor VII: a potential marker of pre-eclampsia

Introduction

Normal pregnancy is associated with a local hypercoagulable state that becomes more profound in certain obstetric complications such pre-eclampsia (P-EC). Current literature on the levels of individual haemostatic factors in women with P-EC is limited and results are inconsistent. In this study we provide detailed investigation on the tissue factor (TF)-dependent pathway in women with P-EC.

Materials and Methods

Enzyme-linked immunosorbent assays (ELISA) were used to measure plasma factor (F) FVII, FVIIa, TF and tissue factor pathway inhibitor (TFPI) in healthy non-pregnant women (n = 22), normal pregnant women (n = 15), and women with P-EC (n = 20). All subjects were age matched. In addition, pregnant women were matched for gestational age, parity and were all at the third trimester.

Results

Plasma FVII levels were significantly higher in women with P-EC compared to the healthy non-pregnant (P < 0.001) or the normal pregnant groups (P < 0.001). No such significant trends were observed for plasma FVIIa, TF or TFPI levels. Plasma FVII levels can distinguish women with P-EC from healthy non-pregnant women or normal pregnant women at the third trimester, with high sensitivity (90%), specificity (80%), positive and negative predictive values (86%).

Conclusions

Plasma FVII levels are significantly elevated in women with P-EC, in the absence of comparable changes in other TF-dependent pathway factors (FVIIa, TF and TFPI). We propose the use of plasma FVII as a marker for P-EC.