Premarin® Horses Fact Sheet

“Nothing has been, or ever will be, appealing or beneficial about the PMU industry and the Premarin family of drugs; they are clearly harbingers of death from both sides of the equation”. 

The Drugs

The most commonly known drugs derived from the estrogen rich urine of pregnant mares are the Premarin® family of drugs.

The mares and byproduct foals are commonly referred to as PMU horses.

The Premarin® family of drugs are hormone replacement therapy (HRT) drugs introduced in 1942 for the relief of menopausal symptoms.

Premarin® was formerly manufactured by Wyeth. Wyeth merged with Pfizer in 2009 and now a Division of the pharmaceutical giant.

The Premarin® family of drugs include Premarin® (tablet and cream), Prempro, Premphase and the recently approved Duavee (called Aprela during the FDA approval process). Duavive was recently approved in Europe.

The active ingredient is correctly referred to as conjugated equine estrogen (or CEE’s).

The word equine has since been removed, a way of distancing the drugs from the nature of how they are produced.

Today Premarin® is reportedly the most widely-prescribed drug for women in North America. It has been estimated that 9 million women are currently taking some form of Premarin®.

It is critical that we step up immediately and inform doctors and warn women about the Premarin® family of drugs and free the horses from the suffering that goes into their making

The Women

In 2002, the Women’s Health Initiative (WHI) study of more than 16,000 women using Prempro, was abruptly halted by the federal government after it concluded that HRT raises a woman’s risk of having a stroke by 41 percent, risk of suffering a heart attack by 29 percent, and risk of getting breast cancer by 26 percent.

Dr. Claude Lenfant—director of the National Heart, Lung, and Blood Institute, which sponsored the study—said the cardiovascular and cancer risks were “too high a price to pay” and urged women who want to ward off heart disease to “focus on well-proven treatments” instead, such as controlling blood cholesterol and keeping their weight down.

The WHI also found that Prempro has no meaningful effects on women’s physical or emotional health, pain levels, memory, sleeping patterns, or energy levels. The researchers concluded that Prempro is effective for short-term relief from hot flashes but nothing else.

Many women find that they can control hot flashes and other menopausal symptoms by making easy lifestyle changes—like eating a low-fat vegetarian diet and getting regular exercise—rather than contributing to animal suffering. Dr. Jennifer Hays from the Baylor College of Medicine commented, “The average woman will not experience an improvement in her quality of life by taking this pill.”

At the time of this writing, Wyeth (now a division of Pfizer) faces more than 5,000 personal injury lawsuits filed by more than 8,000 women who took Prempro or Premarin®.

The Horses

Premarin mares are large bred horses such as Belgian—Quarter Horse crosses, prized for their large bladders.

The mares must wear rubber urine-collection bags at all times which causes chafing and lesions.

For most of their 11-month pregnancies, these horses are confined to stalls so small that they cannot turn around or take more than one step in any direction.

Mares are taken off the “pee line” a couple of months before they foal. Once the foals are born, the mares are re-impregnated. This cycle continues for about 12 years.

Sadly, foals born to these mares are usually worth less than the urine their mothers produce. They are considered to be nothing more than a living byproduct of Premarin®.  To the PMU farmers, they are worth more dead than alive.

Some foals will die soon after birth. Of those whom survive, the majority of them will be sent to auction where they will be sold for slaughter.

A filly foal has a less than 1-in-10 chance of not being sent to slaughter. Some will be kept to replace the worn-out mares on the PMU farms; the rest will be sent to the slaughter auction. A colt foal will have a less than 1-in-50 chance of not being sent to slaughter.

One PMU industry insider says, “See, the foals—and the mares which [sic] can’t get pregnant any more—they are the byproduct of the PMU industry. . . We crush ’em and recycle ’em, just like [aluminum] cans.”

Additional Resources

See also images, Alternatives to Premarin®, Premarin® Timeline, Premstoppers® campaign and our Special Reports »

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