Study finds oral hormone replacement therapy increases venous thromboembolism risk

Summary

A large Danish nationwide study published in The BMJ found that current oral menopausal hormone therapy was associated with a higher risk of venous thromboembolism, regardless of dose or treatment duration. Increased ischemic stroke and heart-attack risks were mainly observed with prolonged use of high-dose oral estradiol. Transdermal therapy using patches, gels, or sprays showed no general increase in thrombotic risk, although one combined cyclic regimen was associated with higher heart-attack rates based on sparse data. Because the study was observational, it cannot establish causation.