A report describes a woman who needed more acenocoumarol when her
HRT treatment with oral conjugated oestrogens was changed to transdermal
estradiol. A retrospective analysis of women starting
HRT found that three needed
warfarin dose increases of about 10 to 30%.
Direct information is limited. Note that, because of the increased risk of developing venous thromboembolism with
HRT, the use of
HRT in women already on anticoagulant therapy requires careful consideration of the risks and benefits. If the combination is used be aware that the anticoagulant response may be affected.