[Contraceptive hormones vascular risk and abnormal precipitation of serum gamma-globulins]

Oral contraceptives (OCs) have always been associated with an increased risk of thromboembolism but only recently a test has been found to detect women who are at a higher risk. The test consists in precipitating the anti-ethinyl-estradiol antibody found in the serum of a woman on OCs by 25% saturated ammonium sulfate at 22 degrees Celsius. The test shows that about 100% of women who had vascular thrombosis while on OCs had a level of gamma globulins (GAP) higher than 600mg. 200 women aged 15-49 were observed and divided into 4 groups: 1) 50 women who were never on the pill; 2) 100 women on OCs; 3) 30 women who had stopped OCs; and 4) 17 women who had had vascular thrombosis while on OCs. Results showed that 1) 90% of cases in group 4 had an increase in GAP level associated with thrombotic events; 2) levels of GAP can remain very high for a long time after discontinuation of OCs; and 3) only about 30% of the total population on OCs investigated showed the presence of GAP. The mechanism of action of GAP in causing thrombosis is still to be demonstrated and it seems obvious that other factors such as smoking intervene to modify the mechanism of GAP.