Venous and Pulmonary Thromboembolism and Combined Hormonal Contraceptives: Systematic Review and Meta-Analysis
January 2012
in “
The European Journal of Contraception & Reproductive Health Care
”
TLDR Some birth control pills have a higher risk of blood clots than others.
The document is a systematic review and meta-analysis that assessed the risk of venous thromboembolism (VTE) associated with combined hormonal contraceptives (CHCs) containing different progestogens. It concluded that CHCs with desogestrel, gestodene, drospirenone, or cyproterone acetate have a higher risk of VTE compared to those with levonorgestrel. The relative risks (RR) for VTE were 1.93 for desogestrel, 1.33 for gestodene, 1.67 for drospirenone, and 1.65 for cyproterone acetate, all compared to levonorgestrel. The safest CHCs in terms of VTE risk were those containing levonorgestrel or norgestimate. The absolute risk of VTE for CHC users was low, with an estimated 8 cases per 10,000 women per year for levonorgestrel users, and 2-7 additional cases for users of other CHCs. The review also highlighted the need for more recent epidemiological studies on the latest CHC preparations.
