Looking for Estrogen?
In particular, estrogen applied topically may have a different spectrum of side-effects than when administered orally, and transdermal oestrogens do not affect clotting as they are absorbed directly into the systemic circulation, avoiding first-pass metabolism in the liver. This route of administration is thus preferred in women with a history of thrombo-embolic disease.
Source: Wikipedia > Estrogen
What is QuickyWiki? QuickyWiki blends the depth of Wikipedia with the ease and speed of Cliffs Notes.