Postmenopausal hormone therapy and risk of venous thromboembolism: what about progesterone?

The UK study by Vinogradova and colleagues provides further evidence that oral but not transdermal oestrogen is associated with increased risk of venous thromboembolism among women who use postmenopausal hormone therapy.1 Previous studies have shown this safety advantage of transdermal oestrogen, together with the important role of concomitant progestogens.23 Progesterone is …