Objective: Pregnancy is accompanied by changes in the coagulation and fibrinolytic systems. There is a marked increase in some of the coagulation factors, particularly fibrinogen and factor VIII. A high plasma levels of coagulation factor VIII is an important risk factor for thrombotic complications during pregnancy and puerperium. The aim of the study was to determine changes of the VIII:C in the early postpartum period. Setting: Dept. of Obstetrics and Gynaecology, Medical Faculty of Palacký University, Olomouc. Design: A longitudinal prospective study of 197 healthy women. Primi or multigravidas whose pervious pregnancies had been uncomplicated, aged 18–41 years. All of the deliveries were spontaneous and vaginal. First samples were taken between 24–72 hours postpartum. Women whose factor VIII plasma levels were higher than 150 (percentage of standard) were tested again after 6 weeks. Factor VIII:C was investigated by the one-step coagulation method. Statistical evaluation was done by Statsoft, Inc. (2001) Statistika Cz (Software system data analysis), version 6. Results: Pregnancy is associated with increased levels of VIII:C. Mean value was 194.09 percentage of standards. 119 (60.4 %) of the tested women had VIII:C higher than 150%. The post-puerperal tests were done in 59 women and showed values similar to those from formerly published data in age-matched non-pregnant group. Mean value was 139.76%. Conclusion: Normal pregnancy is connected with increased levels of factor VIII. However elevated plasma levels of VIII:C is not associated with poor pregnancy outcome. The highest level of the clotting factor VIII was associated with patient’s blood group A. Post-puerperal data showed distinct decrease of factor VIII. There is a necessity to rule out thrombophilia, in the case of the outlasting elevation of the factor VIII.

        Key words: factor VIII, puerperium, thrombosis