from the urine of pregnant mares, Premarin is peddled
by a pharmaceutical multinational as a panacea for
menopausal women. Illustrating a classic nexus of
ecofeminist issues, this essay exposes the
drugs harmful impact on women, animals, and the
environment, and suggests natural alternatives.
article was originally published in 1994 in
The FAR Newsletter.
By Cathleen McGuire
Did you know that synthetic estrogen is a known
carcinogen? Did you know that this popular drug entails the
slaughter of thousands of baby foals? Did you know that most
estrogen prescribed for menopausal women comes from the urine
of pregnant mares?
Increasingly, women approaching menopause are being pushed
by the medical/pharmaceutical industry to consider hormone
replacement therapy. Underneath this ostensible concern for
women's health is an issue that poses enormous consequences
for women, animals, and the environment.
Ayerst, a pharmaceutical company based in Montreal, is a
division of American Home Products, a multinational
corporation. Ayerst has a virtual monopoly on the pregnant
mare's urine (PMU) industry. Their plant, Ayerst Organics, in
Brandon, Manitoba, Canadathe only one in the
worldacquires estrogen-rich urine from approximately 75,000
mares on 485 PMU "farms" in the Prairie provinces
and North Dakota. (In 1992, Ayerst paid PMU producers $44
million for urine, or about $17 a gallon.) Ayerst then ships
the extracted estrogen to its main plants in Montreal and New
York where it is manufactured into Premarin, the world's
leading hormone replacement drug.
Through artificial insemination the mares are all
methodically impregnated to be on the same eleven-month
gestation cycle. Percheron and Belgian draft horses are the
breeds of choice since the larger the animal, the more
plentiful the urine/estrogen yield. From approximately
September to April, when their estrogen production is
highest, the pregnant mares are catheterized and confined to
narrow stalls. An Edmonton newspaper article explains:
"The horses are kept in stalls with a kind of
rubber cup attached to their business end. The urine
drains through a network of hoses to a stainless steel
tank where it's kept chilled until pickup.
"Flexible rubber bands keep the cup in place but
allow a horse to move about in the stall or lie down.
Groups of five are exercised every two or three
Animal rights groups such as the Manitoba
Animal Rights Coalition (MARC), however, claim that in
reality the only exercise the animals get is from sitting
down and standing up. The treatment of the horses is very
similar to that of intensively raised dairy cattle. According
to PMU farmer, Rocky Cartier, "It's paid the same, it's
handled the same as dairies, everything is exactly the same.
In fact, the bulk room where the tank is was altered to dairy
specs two years ago."
Anxious to avoid any hint of a horse abuse scandal, the
industry compiled a detailed Recommended Code of Practice
that farmers must adhere to. Yet groups such as MARC continue
to expose inhumane practices. For example, the average horse
measures eight or nine feet, yet the guidelines allow for
stalls as short as six feet in length. MARC has also been
conferring with a former employee from one PMU farm who
claims she can document the death of seven mares.
Death in fact is a given in the PMU industry. Although
some foals end up as riding ponies in the hands of private
owners, the vast majority of the 75,000 baby horses born each
year are treated as mere by-products. They are separated from
their mothers, and trucked long distances to feed lots where
they are reared for eventual slaughter as horsemeat. Ayerst
refuses to assume any accountability claiming the ". . .
farmersnot Ayerstare responsible for sending the foals to
Tom Hughes of the Canadian Farm Animal Care Trust
"Colts and cull fillies are typically sold by PMU
farms at four to five months of age, just as their
mothers are impregnated again. They may or may not be
fattened by the purchasers before slaughter, depending on
horse flesh prices. Fillies who show the temperament and
conformation to become PMU producers are kept as
replacements for worn out or infertile mares, or are used
to expand production."
Hughes estimates that 300,000 to 400,000 horses a year
(including surplus thoroughbreds, wild horses, and pleasure
horses) are slaughtered for human consumption by the Canadian
horsemeat industry. Since most of the horsemeat is exported
to Europe and Japan (where it is considered a delicacy),
domestic protest has been minimal. With its steady and
plentiful supply of foals, the PMU business guarantees ever
more profits for the expanding horsemeat industry.
With huge numbers of baby boomer women entering menopause,
the equally lucrative hormone replacement business is
positioning itself for a gold rush. Ayerst is pouring $100
million into its Brandon plant, augmented by a $20 million
Western Economic Diversification Fund subsidy from Canada's
federal and provincial governments.
Hailing the expansion as
a "success story," politicians and Ayerst
representativesall menare boasting of increased
employment for the area. Many farmers are eager to be
accepted by Ayerst as PMU suppliers with reportedly ten
applicants for every opening. Les Burwash, a Calgary horse
specialist, claims, "It's a good, sound agricultural
enterprise . . . certainly one of the real bright lights in
What no one is bragging about, though, are the acute
environmental problems resulting from the manufacturing
process. The stench from the by-products is notorious. Ayerst
was allowed to expand operations on condition that they build
a new dumping station to eliminate the noxious animal feces
and ammonia wastes. The dumping station, however, threatens
to overload the city of Brandon's sewage treatment plant.
This would pose serious problems for the water quality of the
Assiniboine River, a source of drinking water for thousands
The water-soluble ammonia is also lethal to
fish and other aquatic life. According to Bill Paton, a
member of Manitobans Against the Assiniboine Diversion,
"Ayerst already has a history of non-compliance with the
Clean Environment Commission and the smell from the plant is
Marianne Cerilli, a Member of the Manitoba Legislative
Assembly, is calling for an immediate basin-wide federal
environmental assessment. Along with her outrage over the
dangers to the environment, Cerilli is also alarmed about the
potential health hazards facing women who take Premarin.
"We should be asking just what the long-term effects of
Ayerst's product will be on the environment of women's
In the 1960s, estrogen was extolled as a wonder drug. It
is now known that there are links between synthetic estrogen
and endometrial cancer, not to mention other "side
effects." In the 1980s, another drug, progesterone,
became routinely administered with estrogen to counteract
cancerous effects. Proponents of Premarin cite its
effectiveness for the prevention of osteoporosis and relief
from vaginal dryness, hot flashes, and other menopausal
The U.S. Department of Health and Human Services,
however, estimates that only fifteen percent of women find
menopause "disruptive" enough to seek
"treatment." For those fifteen percent who do feel
they would like help, primary questions remain: Have the full
effects of Premarin been thoroughly investigated? Can we
trust Ayerst's test data? Does Ayerst use lab animals as
In response to the ethics of using Premarin, some doctors
have indicated they would be willing to prescribe
cruelty-free alternatives. Laboratory-made substitutes such
as Estraderm (Ciba Pharmaceuticals), Estrace (Mead Johnson),
and Ogen (Abbott Labs) have been recently approved by the
Food and Drug Administration. The downside is that these
lab-made synthetics are about twice as expensive, and once
again, we do not know the full extent of their dangers or the
degree of animal experimentation involved.
Ultimately, I regard all synthetic hormone replacements as
one big toxic experiment on women. There are natural
estrogen alternatives that mainstream sources rarely mention.
I would like to share my own experience.
When I was twenty-five, I underwent a hysterectomy,
trusting my doctor knew what was best for me. Although my
uterus, Fallopian tubes, and ovaries were severely afflicted,
there were no signs of malignancy. Nonetheless, my
gynecologist adhered to an AMA tradition: When in doubt, cut
them out. (Funny, if one gets a fat lip, cutting it off is
not usually advised.) He then warned me about the dangers of
osteoporosis, a lowered voice, and the possibility of growing
facial hair. Faced with either risking these disturbing
consequences or taking synthetic estrogens, I barely gave it
a second thought. I took Premarin without fail for over
fourteen years, eventually adding synthetic progesterone.
A few years ago, however, I became involved in a monthly
menstrual circle. We celebrated women's ability to cycle in
rhythm with the moon and the primordial healing power of
women's menstrual wisdom. I began to explore the politics of
surgical menopause and the pharmaceutical-industrial
complex's encouragement of synthetic hormone replacement
I asked my gynecologist (now female and feminist)
about holistic alternatives to synthetic hormones. She had no
clue. Schooled on medical journals that are tethered to
pharmaceutical advertising revenues, she consistently
rejected non-synthetic estrogen possibilities.
I finally found a chiropractor/clinical nutritionist who
helped me traverse new terrain. I no longer take synthetic
hormones. I now get my estrogen and progesterone naturally
from supplements derived from soybeans and wild Mexican yams
respectively. Because natural estrogens present none of the
dangerous side effects frequently associated with synthetic
estrogens, I am convinced they are a much safer hormonal
To maximize the potential for success, I am also
on a sugar-free, organic vegan diet, and a daily regimen of
vegetable juice, vitamin supplements, and exercise.
Vegetarians generally have lower estrogen levels, which
contributes to an overall decrease in risks.
In the controversial world of hormone replacement therapy,
it is anyone's guess which protocol will prove lastingly
effective for menopausal women. I for one decided I would
rather pursue a more holistic path centered around natural
plant derivatives than subject myself to environmentally
harmful, potentially carcinogenic drugs extracted from the
urine of pregnant, oppressed mares.
Animal People: "Estrogen therapy fills horse meat
slaughterhouses," July/August, 1993. "Estrogen Boom
Brings Breeding for Slaughter," April, 1993.
"The Business of Estrogen Production, the Environment
and Women's Health," Marianne Cerrilli, February, 1993.
The Edmonton Journal: "Pee is for profit as farmer
`milks' mares." Don Thomas, October 25, 1992.
Ms.: "What, Menopause Again?," Margaret Morganroth
Gullette, July/August, 1993.
New York Post: "65,000 Horses Born To Be
Slaughtered," Ransdell Pierson, July 26, 1993;
"Doctors cry `foal' over equine victims," Randall
Pierson, July 26, 1993.