Human platelet aggregation curve and oral contraception

In a series of in vitro experiments, the authors investigated the different aspects of the aggregation curves of human blood platelets taken from a group of women who received oral contraceptives, another group of women who did not receive oral contraceptives and a group of men. The platelets were subjected to ADP stimulation. The authors showed that at the lower doses (0.44 and 0.88 . 10(-6) M) of ADP the aggregation and the disaggregation of the platelets from the women who received oral contraceptives was significantly greater than that of the two other groups. The authors proposed that these may be due to an increase of the sensitivity of the platelets to the aggregating stimuli in that group of women who were under oral contraception.