April 2009 Transdermal delivery of estrogen therapy available by prescription “seems not to alter” the risk of venous thromboembolism (VTE), or blood clotting, in postmenopausal patients when compared to oral delivery, a new study suggests. The study was conducted by researchers at NYU Langone Medical Center and was published in the latest issue of Menopause: The Journal of the North American Menopause Society. Prescription transdermal estrogen therapy is bioidentical to estrogen produced by a woman’s ovaries before menopause and delivered through the skin. Transdermal estrogen is available in a variety of formulations which have been quality controlled and approved safe and effective by the United States Food and Drug Administration.