The significance of circulating antiethinyl-estradiol antibodies (AEEA) in the occurrence of thrombosis in women while taking the pill.

The aim of the study was to investigate the hypothesis that oral contraceptives (OC) lead to antiethinyl-estradiol antibody (AEEA) synthesis which might in turn be responsible for the thrombo-embolic complications observed in women users. The trial included 428 women divided into a) 204 healthy female volunteers as the control group (CONT), b) 139 women who had suffered thrombo-embolic accidents (THR), c) 85 women suffering from recurrent fetal loss (RFL). In each of these three categories, 50% were pill users (OC+) and 50% were not (OC-). Specific immune markers of systemic autoimmunity and anticardiolipin antibodies were looked for, as they are thought to be present in increased amounts in thrombosis or recurrent fetal loss. The AEEA prevalence differed significantly (p less than 0.05) between the CONT OC+ (32%) and the CONT OC- (13%) women. It also differed (p less than 10(-5)) between the RFL OC+ (60%) and the RFL OC- (12%) women. It did not differ between THR OC+ (36%) and THR OC- (39%) women. Within the OC+ women, the difference between the THR and the CONT groups was not found to be significant, whereas it was found to differ significantly between the RFL and the CONT groups (odds-ratio RFL/CONT estimated at 3.20, confidence interval 1.53, 6.69). Within the OC-women, the AEEA prevalence was found to differ significantly between the THR (39%) and the CONT (13%) groups (odds-ratio THR/CONT estimated at 4.40, confidence interval 2.07, 9.38%) but not between the RFL and the CONT groups.(ABSTRACT TRUNCATED AT 250 WORDS)