Does the route of administration of hormones make a difference?
Most of the data on the long-term health effects of hormones come from studies involving estrogen and/or progestin pills. Other routes of administration of hormones are available, such as transdermal patches, estrogen gels, and vaginal creams and rings. These forms of estrogen are all equally effective methods of treating the symptoms of menopause, such as hot flashes and vaginal dryness. There is also evidence to suggest that transdermal estrogen patches have beneficial effects on blood lipids, cholesterol, and bone, although many of these benefits are reduced as compared to hormones administered orally. Several studies have found the benefit of transdermal products on bone density and bone metabolism to be comparable to that of oral therapy (83, 103, 82). The amount of estrogen that enters the blood stream from estrogen-containing vaginal creams and rings depends on the types of hormones and the dose. Generally, vaginal administration of hormones will result in lower levels of circul
