What if a woman has thrombophilia but has never developed a blood clot?

Women with thrombophilia are at increased risk of developing blood clots; in fact, the risk of a thrombosis in women with thrombophilia exceeds 1 in 100 per year. Use of birth control pills containing an estrogen and a progestin increases a woman’s chance of developing a blood clot by another three to four times. For this reason, most women with thrombophilia should not use a birth control method that contains estrogen. They may use progestin-only contraceptives such as Micronor®, Nor-Q.D..®, and Ovrette®; the levonorgestrel (Mirena®) intrauterine device (IUD); and every-three-month injections of medroxyprogesterone acetate (Depo-Provera®).