Dangers of hormone therapy

Dangers of hormone therapy

A new study is sounding an alarm for women who take hormone replacement therapy (HRT) that includes both estrogen and progestin.

The research shows an increased risk of developing breast cancer and death among women who begin combined HRT just as menopause begins.

As part of the study, published in an issue of the Journal of the National Cancer Institute, researchers followed nearly 42,000 women past menopause for more than 11 years.

A little more than 25,000 of the female participants did not use hormone therapy. And more than 16,000 received combined estrogen and progestin hormone treatment.

The results
At the conclusion of the follow-up period, researchers found that more than 2,200 of the women who received combined therapy developed breast cancer–significantly more those who didn’t.

The link between combined hormone therapy and breast cancer is not new. But of particular note in this study, was the fact that the breast cancer risk was greatest among those women who received the treatment closest to menopause.

In a statement one of the lead authors for the study said, “Women starting within months of menopause had about a threefold greater risk than women starting 10 years after menopause.”

Dr. Heidi Memmel, breast surgeon at Advocate Lutheran General Hospital in Park Ridge, Ill., says the news is not surprising.

“We have known for years that combination hormone therapy taken for many years increases the risk of developing breast cancer,” she says. “This study confirms that, and gives us more important information about the timing of this treatment.”

Why are risks higher for women closer to menopause?
Researchers speculate the higher risks for women who begin combined hormone therapy closer to menopause may be tied to the fact that they still have higher circulating levels of estrogen, which makes them exceed hazardous thresholds

They also say progestin may be a factor as well.

Timing is everything
Dr. Memmel says the new analysis could signal how important timing is to starting hormone therapy.

“This study displays the increased risk with long-term combination hormone therapy, and is the first large study to take a closer look at the timing of the treatment,” she says. “It shows that physicians should not only be concerned with how long women are taking this therapy, but actually when they initiate it.”

Still, she says additional studies are needed to provide more evidence regarding the timing of HRT.

In the meantime, Dr. Memmel says physicians should try to minimize the use of hormone therapy until it is most needed to manage severe symptoms of menopause.

“We have to balance quality of life with risk,” she says.

For more information on breast health, join Dr. Memmel for a special pink edition of AdvocateLive on Friday, October 4 at 11:30 am.

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  1. I have only read that this is true for standard HRT and not Bioidentical. Has there been a change, or did the study compare HRT vs. Bio-identical hormones? Bio-identical hormones are monitored closely with dose changes made based on the patients lab results.

  2. Thanks for your question Diana. The study did not compare HRT with Bio-identical hormones. I will look for a current study on Bio-identical hormones and do a follow up story on what researchers are seeing with this treatment. Great question!

  3. I have seen similar studies and they have said it’s the progestin, which is why my doctor has put me on progesterone. Apparently it’s safer. Has there been a study that compared progestin and progesterone? I take prometrium. Also, my doc said there was a study of female ob/gyns and only 30% of their patients are on HRT but 70% of the docs take it themselves. Interesting!

  4. I just want to add here that my mom, my aunt, and their first cousin all took premarin for an extended amount of time due to the onset of menopausal symptoms. ALL THREE developed breast cancer and were diagnosed at age 75. ALL THREE then experienced metastasized breast cancer to other parts of their bodies. Coincidence? I think not. My sister and I have vowed to never let a doctor convince us to take any HRT.

  5. This information again contradicts other recently published articles promoting the benefits of hormone replacement therapy. Not sure if this is based on old information or incorrect information. The newest information points to an increased risk of breast cancer from synthetic progestin (Premarin). The newest information shows there is tremendous benefit to a woman’s overall health then taking bio-identical hormone replacement therapy, especially estrogen, including a decreased risk of breast cancer. Who is right and who is wrong?

    • I am 64 and I have been on HRT since 40 yrs of age. I did my homework even back then and knew that Progestin was a no no. My doctor even confirmed that. I am using an estrogen patch and I do quite well with it. Also just want to say that a lot of women do not eat properly and indulge in things like drinking, smoking etc which all contribute to the overall impairment of fighting off cancer cells. But either way I believe Progestin is the culprit. A study like this does not narrow it down to one or the other so it is not accurate.

  6. Premarin is NOT synthetic. It is from pregnant mares urine. The name is taken from that. It contains equine (horse) hormones. In addition, the mares they get the urine from are treated w cruelty. I’m supposed that PETA or a similar group has not gotten after them. They are kep constantly pregnant & kept in their stalls w a collection device on them to collect their urine. The resulting foals are often then killed.

    I’m a human woman–not a horse! I get angry at the way they experiment on us women & of course most of the studies are funded by big pharma so they don’t test natural progesterone cream which is available over the counter. Also many of the studies are very careless & do no distinguish between synthetic progestins vs natural progesterone.

    They also jump to accepted conclusions w out distinguishing which hormones may be the cause of the observed effects. I actually emailed the authors of a study I read about who credited the effects to lack of estrogen after removing ovaries. I points out it could have also been lack of progesterone. They actually replied & agreed & said testosterone could also be involved. That study had to do w the connect to dementia.

    It’s also hard to even find out what is in hormone treatments. Ones like Premarin just say conjugated estrogens. I guess that is to disguise that they are not human estrogens but horse ones which are similar but different. & they don’t distinguish between the different types of human estrogen: estriol, estradiol & estrone. Typical treatments use estradiol which I understand has been more associated w adverse effects.

    It would be nice if more would study what happens w natural hormones in the body & use what is closest to that rather than using substitutes w different composition & probably different effects, including how it is metabolized.

  7. I had a complete hysterectomy when I was only 38. I’ve been taking HRT Estratest for 20 years and even though my primary care physician has warned me of potential health risks, I refuse to give it up. I’ve been on Estratest HS for 10 years and the benefits out weight the potential health risk. Considering there has not been any breast cancer, heart issues or other considerations that would cause me to stop the Estratest and go on Premarin, I have chosen to continue my HRT therapy. I am now 62 and the benefits are wonderful….improvement in skin, bone, energy, sex drive, mental alterness, no weight gain, ability to maintain good muscle tone, etc. etc.

  8. It’s unbelievable how long the medical establishment can keep their heads buried in the sand. This idea that these women get more breast cancer because they have higher amounts from their ovaries is sheer nonsense because once you take HRT the ovaries shut down. A decade ago the NIH advised that post-menopausal women take testosterone (T) to prevent breast cancer. Yes, TESTOSTERONE! THE OVARIES MAKE THREE HORMONES, NOT TWO!! Seven years ago the Karolinska U. proved beyond any doubt that the lack of T caused severe pre-cancerous changes in breast tissue. And within the past weeks a study was published showing that women on T replacement for five years had a 76% REDUCTION IN THE RATE OF BREAST CANCER! And there are many more studies confirming the relationship between T deficiency and breast cancer. WAKE UP! IF WOMEN REPLACED THEIR T WHEN THEY STARTED TO LOSE IT BREAST CANCER WOULD BECOME A RARE DISEASE!

  9. I took the natural bioidentical type for 12 years following menopause, at first Ogen and Prometrium then went to Estradiol and Prometrium. I am in treatment for breast cancer now and know beyond a doubt these hormones caused it. I would have never suspected cancer when my left breast developed a strange sensation, almost like little pains so I went in and my dr. ordered a diagnostic mammogram and sure enough it turned out to be Stage 2 invasive breast cancer! I had stopped the hormones a while before that thinking it might help and it did somewhat but the symptoms did not go away so here I am at age 65 facing surgery in a few weeks to remove the tumor and am otherwise very healthy and no history of it in my family. In one of the posts above it reads that 70% of doctors take the hormones, well that is just plain WRONG! 70% do NOT take them bec they know better! and what they can cause. I don’t even miss the hormones now that i have been off them for awhile but it does take awhile for the body to adjust. Breast cancer is rampant! and hormones include birth control pills as well so if yu ever took those, they count too.

  10. The media never differentiates between the synthetic Premarin/Provera (progestin) and bio-identical estrogen/progesterone. I have fired my ob-gyn of 15 years because he is a drone of the pharmaceutical companies that support him. I have been on bio-identicals for three years and feel better than I did at 25. I am mid-50’s and ANGRY that bio-identicals were not available to me years ago. I had mind boggling PMS and begged for help. My dr also told me “we know it’s hormone imbalance but we can’t do anything about it. quit drinking coffee.” I started the bio’s and never had ONE DAY of PMS afterward. I get bloodwork twice a year to keep the BALANCE between all hormones—-estrogen, progesterone, testosterone, insulin, thyroid, cortisone. PLEASE do your homework and understand the synthetics are a different molecule than the bio. The bio is what your body recognizes and knows what to do with it. The synthetic is FOREIGN and is a toxin.

  11. I take bio-identical estrogen patches and PROGESTERONE have switched to prometrium which is available from my pharmacy. Read the studies carefully make sure you are not reading the effects of mare’s pee pee on women. I discussed it with my OBGYN and decided the benefits to my overall health and bones outweigh the unknowns. She agreed with me.

  12. The study I read compared three types of therapy.
    One with both estrogen and premarin.
    One with premarin only.
    One with estrogen only.

    The estrogen only group had a significantly lower risk than either of the other groups!
    This article did not mention the group with the lover Percentage. What gives?

  13. I started on the HRT combination when I started menopause at age 51 and took it for 10 years. I do have mammograms faithfully every year, but still worry about breast cancer. My doctor at the time told me I would probably be taking it for the rest of my life, but I stopped it on my own when I heard they had ended the study, because of the increased breast cancer risk and the HRT didn’t protect your from osteoporosis or heart attacks. Now I’ll be worrying the rest of my life (age 71 now).

  14. My mother took Premarin for 30 yrs after a hysterectomy at age 50. My sister in law took Premarin for longer than that. Both did very well, no breast cancer. I know quite a few women with breast cancer that never took hormones. That’s all I can relate is what I know of personally. I, myself, started bioidentical at age 56. I’m now 70 with no heart trouble, high blood pressure, or cancer of any kind. I do believe that each woman is different and also more attention needs to be paid in relation to the levels. One size doesn’t fit all.

  15. I was in my first year of menopause when my DR gave me hysterectomy cuz my bladder was falling out. he gave me estradiol. hi blood pressure runs in my family and I have it. this pill caused my BP o go up to 160/100. stopped taking it. BP went down to 120/ 80 within two days. other risks to HRT besides cancer.

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health enews Staff
health enews Staff

health enews staff is a group of experienced writers from our Advocate Health Care and Aurora Health Care sites, which also includes freelance or intern writers.