Did you know that Premarin is made from horse urine? 
This originated in the 1950′s, estrogen derived from pregnant horse urine. And since then, it has been the main source of estrogen made by pharmaceutical companies recommended for the symptoms of menopause.
Did you know that Premarin contains fifty different forms of estrogen, only three of which being known to occur naturally in humans.
Since drug companies can not patent a natural structure, they invent hormones that are patentable. A few of these are Premarin, Provera and Prempro.
As Dr. Hargrove, a former medical director of the Menopause Center at Vanderbilt University Medical Center in Tennessee has said, “Premarin is a natural hormone if your native food is hay.”
In her book, The Hormone Solution: Naturally Alleviate Symptoms of Hormone Imbalance from Adolescence Through Menopause , Dr Erika Schwartz says, “You must understand it has been proven that once broken down in our bodies, conjugated equine (Premarin) becomes toxic to the DNA that keeps us healthy or makes us sick.” Okay it is not good for our bodies and if you are an animal lover, it is a sad existence for the horses involved and their babies that have been sacrificed for sixty years.
Natural really isn’t a good term for describing the hormones used to make hormone replacement therapy. This is a subject you are going to have to do research on for yourself in order to make your own decisions for your body.