Bilateral ileofemoral thrombophlebitis after ten contraceptive pills in a 25-year-old woman with antithrombin III deficiency.

A case of bilateral deep venous thrombosis of the legs in a 25-year old woman who had taken 10 low-dose combined oral contraceptive pills (Trigynon Schering) with no other predisposing factors is presented. Trigynon contains 0.35 mg ethinyl estradiol and 0.60 mg levonorgestrel and has been reported to cause only minor if any change in clotting factors. The woman was suspected to be heterozygous for antithrombin III (ATIII) deficiency with ATIII activity 60 and 50% of normal by the chromogenic and Laurell antigen methods respectively. Clinically she developed pain in the left inguinal area on day 10 swelling of the right leg a few days later and was admitted and diagnosed with parietal thrombi in both iliac veins and the left popliteal vein on day 17. Contraceptives were discontinued and she recovered after treatment with anticoagulants. Thrombosis did not recur after pills were discontinued. Her maternal relatives were known to suffer from thrombophlebitis. This experience indicates that combined pills should not be prescribed to patients with ATIII deficiency.