Premarin: What are Synthetic Hormones?

In the 70's, when Provera was invented, Premarin, the "Prem" in Prempro, was prescribed alone. This low-dose chronic horse estrogen caused uterin cancer by fostering an overgrowth of the lining of the uterous. Originally, a doctor aiming to replace hormones only prescribed estrogen replacement therapy (ERT). But once the epidemic increase of uterine cancer was identified, instead of pulling Premarin from the shelves, Upjohn, the original maker of MPA, invented another drug out of natural progesterone.

The molecule of natural progesterone found in a compound called genistein in plants was chemically altered into a patentable drug that has been proven to have life-threatening side effects like heart disease, breast cancer, stroke, and dementia. The two drugs were eventually packaged together and remarketed as PremPro to prevent the horse estrogen from causing uterine cancer, and increase the market share to women with uteruses.

However, unlike real progesterone, which has a rhythmic, cyclical presence in your body two weeks out of every month, if you take Prempro, you recieve Provera every day. In actuality this combination of horse estrogen and fake progesterone can't ever recreate a normal cycle, so although it's marketed as HRT, it's not. It's not really hormone replacement for two reasons: 1) because it's a drug, and 2) because it's prescribed in a static dose, which has no resemblance to what used to go on hormonally in your body when you were in your prime.

In the end, the static, chronic dose of a progestin like Provera in a combination dose with an animal-source estrogen like Premarin blocks the horse estrogen's effect every day. So any benefits known to result in heart, brain, and breast from estrogen are lost or diminished. Even though this combination drug can cause breast cancer, heart disease, and dimentia, it's still widely available to women all over the world