The coagulation system during caerean section. Coagulation, fibrinolysis and hormonal levels in peripheral and uterine venous blood during caesarean section.

Abstract

Abstract. Some parameters of blood coagulation and fibrinolysis have been studied in peripheral and uterine blood during elective Caesarean section in ten women. The levels of estradiol and progesterone were also studied. Before the operation there were lower levels of fibrinolytic inhibitors in uterine blood than in peripheral blood. Therefore the inhibitors present in the placenta seem to be restricted to the fetal circulation. During the course of the operation, there was a shortening of the activated partial thromboplastin time, APTT, in peripheral and uterine blood. The number of platelets and the factor VIII activity increased in uterine blood, and the values in peripheral blood also tended to increase. These changes speak in favour of a general clot promoting tendency after placental separation. After placental separation there was a lower plasminogen level in uterine blood compared to peripheral blood which supports a hypothesis of local uterine fibrinolysis after placental separation. The level of estradiol and progesterone in peripheral blood did not change during the operation. In uterine blood the concentrations of both hormones tended to decrease. No correlation was found between the levels of the hormones and the parameters of coagulation and fibrinolysis.