1*Division of Gastroenterology and Hepatology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; Center for Gastrointestinal Biology and Disease, Chapel Hill, North Carolina; and †NIH, Epidemiology Branch, National Institute of Environmental Health Sciences, North Carolina.
Persons with inflammatory bowel disease (IBD) have an increased risk of venous thromboembolism. We sought to examine whether the self-report of hormonal contraception (HC), as a proxy for exposure to estrogen-based contraception, was less common for women with multiple risk factors for venous thromboembolism.
We examined the prevalence of personal use of hormonal birth control in a large internet-based cohort of patients with IBD. To determine whether HC was less common among patients with IBD with increased risk of thrombosis, we estimated unadjusted and adjusted prevalence ratios (PRs) for the use of HC.
Thousand four hundred ninety-nine female survey respondents answered optional fertility questions and were included in the analysis. The prevalence of HC was 33.7% (95% CI, 30.6%-36.9%) among women with Crohn's disease and was 32.6% (95% CI, 28.6%-36.8%) for women with ulcerative colitis. Women with one risk factor for thrombosis were not significantly less likely to receive HC (PR = 0.91, 95% CI: 0.76-1.08; adjusted PR = 0.94, 95% CI: 0.80-1.11) compared with women without risk factors nor were women with 2 or more risk factors (PR = 1.10, 95% CI 0.56-1.28; adjusted PR = 1.10, 95% CI: 0.83-1.45). The use of an intrauterine device was also similar between women with and without risk factors for venous thromboembolism.
The prevalence of HC use in women with multiple risk factors was similar to that in women without risk factors, which represents an opportunity for prevention. Gastroenterologists should ask patients with IBD using HC about risk factors for thromboembolic disease to identify patients who may benefit from alternative contraception.