Pre-eclampsia (P-EC) is a rnultisystem disorder exclusive to pregnancy. It complicates similar to 2 to 8% of all pregnancies and remains a major cause of maternal mortality. P-EC is characterized by a profound hypercoagulable state. The delicate hemostatic balance that must be maintained in the uteroplacental circulation during pregnancy makes this system vulnerable to perturbation. An abnormal hemostatic pattern occurs within the uteroplacental circulation in P-EC compared with normal pregnancy. Much recent research has focused on the epidemiological link between inherited thrombophilia and P-EC. The data suggest a weak statistical association, indicating an improbable primary role in the pathogenesis. Without clear evidence, low molecular weight heparins have been widely used to reduce recurrence of P-EC in thrombophilia-positive women. This practice now should be reviewed. Future research needs to focus on improving our basic scientific understanding of the role of the hemostatic system in human placentation.