Hormone replacement therapy and risk of venous thromboembolism in postmenopausal women: systematic review and meta-analysis.

Authors: Canonico M, Plu-Bureau G, Lowe GD, Scarabin PY.

Publication Year: 2008

Citation: BMJ 2008;336(7655):1227-31

This meta-analysis of 17 studies of postmenopausal women found that those using oral estrogens had an increased risk of thromboembolism compared with those using transdermal estrogens, particularly during the first year of treatment.  Even in women with pre-existing risk factors for thromboembolism, transdermal estrogen use did not confer additional risk.

http://www.ncbi.nlm.nih.gov/pubmed/18495631