Hormonal contraception and risk of thromboembolism in women with diabetes

Abstract

OBJECTIVE: To investigate safety of hormonal contraception with regard to thromboembolic events in women with type 1 or 2 diabetes. RESEARCH DESIGN AND METHODS: We used data from 2002-2011 in Clinformatics Data Mart to identify women in the U.S., 14-44 years of age, with an ICD-9-CM code for diabetes and a prescription for a diabetic medication or device. We examined contraceptive claims and compared time to thromboembolism (venous thrombosis, stroke, or myocardial infarction) among women with diabetes dispensed hormonal contraception using a modification of Cox regression to control for age, smoking, obesity, hypertension, hyperlipidemia, diabetic complications, and history of cancer; we excluded data for 3 months after women gave birth. RESULTS: We identified 146,080 women with diabetes who experienced 3,012 thromboembolic events. Only 28%of reproductive-aged women with diabetes had any claims for hormonal contraception, with the majority receiving estrogen-containing oral contraceptives. Rates of thromboembolism were highest among women who used the contraceptive patch (16 per 1,000 woman-years) and lowest among women who used intrauterine (3.4 per 1,000woman-years) and subdermal (0 per 163woman-years) contraceptives. Compared with use of intrauterine contraception, progestin-only injectable contraception was associated with increased risk of thromboembolism (12.5 per 1,000 woman-years; adjusted hazard ratio 4.69 [95% CI 2.51-8.77]). CONCLUSIONS: The absolute risk of thromboembolism among women with type 1 or 2 diabetes using hormonal contraception is low. Highly effective, intrauterine and subdermal contraceptives are excellent options for women with diabetes who hope to avoid the teratogenic effects of hyperglycemia by carefully planning their pregnancies.