Premarin causes controversy
There are few drugs in modern history that have stimulated greater controversy than Premarin. Since its FDA approval in the early 1940s, more than 30 billion doses have been dispensed. The estrogens in this hormone replacement therapy are made from purified pregnant mares’ urine.
By the 1960s, Premarin was widely prescribed to ease menopausal symptoms. Not only was it used to eliminate hot flashes and night sweats; doctors prescribed it to calm anxiety, slow the aging process and help women stay "Feminine Forever." That was the name of a popular book written by physician Robert A. Wilson in 1966.
Since then, Premarin has been praised and vilified by doctors, patients and consumer advocates. Even 40 years later, the controversy rages on. Epidemiologists continue to argue about the risks and benefits of HRT. On March 7, 2012 an online article in The Lancet Oncology suggested that estrogen by itself (without progestin or medroxyprogesterone) does not increase the risk for breast cancer and might even lower it. The key author (Garnet Anderson) was quoted as saying, "Women who have had a hysterectomy may be reassured that taking estrogen by itself, short term, to relieve menopausal symptoms will not increase their risk of breast cancer."
Sounds convincing and very reassuring. But 25 days later on April 1, 2012 (not an April Fool's joke, we assure you), a much larger study was presented at a cancer conference in Chicago with just the opposite results. The research involved roughly 60,000 nurses who participated in The Nurses Health Study. Data was analyzed from 1980 through 2008. Women who took both estrogen and progesterone (Prempro for example) had an 88 percent higher risk of breast cancer after 10 years on the treatment. Those who took estrogen alone for at least a decade had a 22 percent increased risk of developing breast cancer. Those women who were exposed to just estrogen for more than 15 years had a 43 percent greater chance of being diagnosed with breast cancer. The lead author, Dr. Wendy Chen, is quoted as saying, "There's a continued increase in risk with longer durations of use, and there does not appear to be a plateau."
With such conflicting research and dueling headlines (one month you read that "Estrogen Pills Reduce Breast Cancer Risk" and the next you see that "Long-Term Estrogen Therapy Does Up Breast Cancer Risk"), it is hardly any wonder women are totally confused.
The experiences of individual women often get lost in the clamor.
Some women, like this one, strongly favor the drug: "I had a complete hysterectomy in 1974 due to endometriosis, a very painful disease involving my uterus and ovaries. I took Premarin but did not take progestin since I had no uterus. I have heard that progestin is what may increase the risk of cancer for women taking estrogen.
"Nothing terrible has happened to me all these years on Premarin. At 79, I'm healthy and play tennis and golf regularly."
Another woman had a serious side effect, but still opts for Premarin: "After I had a hysterectomy, I was put on a high dose of Premarin for menopausal symptoms. I stayed on it for 30 years. Two years ago, I was diagnosed with early breast cancer. I had a lumpectomy and 7 weeks of radiation. The cancer has not returned.
"Would I do it again? You bet! Surgery and radiation are a small price to pay for 30 years of health and happiness."
Here is a different perspective: "In the mid-1980s, my doctor talked me into taking estrogen for night sweats and lack of sleep. In 1998, after taking estrogen all that time and getting annual mammograms for 12 years, I was diagnosed with early stage breast cancer.
"I needed a lumpectomy and five weeks of radiation. The first thing I was told was to stop taking estrogen. Not long after that, the uproar started over HRT and many women stopped taking it. After 12 years, I was breast cancer waiting to happen. I took it that long because I was told it was good for my bones.
"In 2006 I found out I had uterine cancer. I'd had symptoms for only a few weeks before they performed a hysterectomy. The doctor said the cancer was about to break through the lining of the uterus. I guess I was lucky. Again, I needed five weeks of radiation. This time it was much harder.
"I have to wonder if any of this would have happened had I never agreed to take the estrogen. I guess I'll never know."
Proving that HRT was responsible for a particular woman's cancer is very difficult. The stories of these three women demonstrate why individual preferences must be part of the prescribing decisions. Weighing benefits and risks based on objective information is critical to that process. The latest data from the Nurses Health Study seems to confirm that use of hormones beyond 10 years increases the risk of breast cancer. That includes estrogen by itself or combined with progesterone. Whether so-called bio-identical hormones would be any safer remains to be determined.
For more information about treating menopausal symptoms and hot flashes without estrogen or progesterone, or a combination of the two, we suggest our Guide to Menopause or The People's Pharmacy Quick & Handy Home Remedies from National Geographic.
You can find both in our People's Pharmacy Store.