Demir, CengizDilek, Imdat2025-05-102025-05-1020101807-593210.1590/S1807-593220100011000112-s2.0-78951491323https://doi.org/10.1590/S1807-59322010001100011https://hdl.handle.net/20.500.14720/9841Demir, Cengiz/0000-0001-9856-184XINTRODUCTION: The etiology of preeclampsia is not fully established. A few studies have shown a relationship between natural coagulation inhibitors and preeclampsia. OBJECTIVES: The purpose of this study was to investigate the status of natural coagulation inhibitors and active protein C resistance (APC-R) in preeclampsia. PATIENTS AND METHODS: We studied 70 women with preeclampsia recruited consecutively and 70 healthy pregnant and 70 nonpregnant women as controls. Plasma protein C (PC), free protein S (fPS), antithrombin III (ATIII) and APC-R were evaluated. RESULTS: ATIII values were found to be significantly lower in preeclamptic patients than in the control groups (p < 0.001). Nevertheless, there was no significant difference between the healthy pregnant and nonpregnant women groups (p = 0.141). The fPS values of the preeclamptic and healthy pregnant groups were lower than that of the nonpregnant group (p < 0.001), and the fPS value of the preeclamptic pregnant women was lower than that of healthy pregnant women (p < 0.001). The PC value of the preeclamptic pregnant women was lower than that of the control groups (p < 0.001). The PC value of the healthy pregnant women was lower than that of the nonpregnant women (p < 0.001). The mean APC activity values were lower in the preeclamptic patients than that of the control groups (p < 0.001, p < 0.001). The APC-R positivity rates of the preeclamptic groups were higher than that of the control groups (p < 0.001). CONCLUSIONS: This study demonstrated that ATIII, fPS, PC values and APC resistance were lower and APC-R positivity was higher in preeclamptic women than in normal pregnant and nonpregnant women.eninfo:eu-repo/semantics/openAccessNatural Coagulation InhibitorsApc-RRiskPathogenesisPreeclampsiaArticle6511Q3Q11119112221243283WOS:000288492000011