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HRT - The Facts

Modern HRT is BIO-IDENTICAL and derived from NATURAL SOURCES


Modern HRT has the same molecular structure to the hormones we naturally produce in our body
It is derived from the Mexican Wild Yam – a root vegetable  

So why are we all scared of HRT?


The most common reason women give for not wanting to take HRT is the fear of breast cancer.

This started because of the Women's Health Initiative (WHI) trial - which was a huge study in the 90s that was looking at HRT and heart disease. In 2002, there was a dramatic press conference and it was announced that the study was stopping early due to an increased risk of breast cancer, clots and heart disease – this led to millions of women stopping their HRT and it made most doctors stop prescribing it.

20 years later and we are still feeling the effects of this flawed study and many women have been left needlessly suffering with menopause symptoms ever since.


What was wrong with the WHI trial?


  • It focused on older women (the average age was 63)

  • It looked at older types of HRT (synthetic oral estrogen and synthetic progestins)

  • It included women with other risk factors for developing breast cancer (such as obesity and family history)


Since then, lots of other studies and re-analyses of the original data have come out and concluded that the benefits of HRT far outweigh the small potential risks.


What did the WHI trial actually find?


Breast cancer risk

Taking combined HRT (estrogen and progesterone) led to an extra 8 cases of breast cancer per 10,000 women per year, only after 5 years of use (there was no difference in risk with less than 5 years of use)

This increase was so small it was not statistically significant.


This risk of getting breast cancer from combined HRT is lower than the risk of getting breast cancer from being overweight.


It is also lower than the risk of getting breast cancer from drinking 2 or more alcoholic units per day.

The women who took estrogen-only HRT (these are women who had a hysterectomy and could choose not to take any progesterone) had lower risks of breast cancer than women not taking any HRT.


Taking estrogen-only HRT has been linked to reduced risks of breast cancer


But for some reason, estrogen came out of the WHI study as the bad guy, and progesterone came out as the good guy.

The natural health industry started to promote and sell unregulated progesterone products as the 'safer' and more natural alternative to HRT.

Even though it was the addition of the progesterone that led to any increased risk of breast cancer. 


Heart disease risk

The whole reason the WHI trial was done was to look at whether HRT could help prevent heart attacks in older women. So they were giving HRT to women in their later years - some were in their 70's. Many had never taken HRT before. 

It was already well known that women have a lower risk of heart disease than men - until they reach menopause. The hormones our ovaries make are good for our hearts. After menopause, women's risk matches that of men's. 

When the WHI team looked at the overall results, it showed that HRT was increasing the risk of heart attacks.

But! - when they just looked at the women aged under 60, or within 10 years of their last period - it was the opposite effect.


When started under the age of 60, HRT reduces the risk of heart disease - the number one killer of women


This is the age group we most commonly give women HRT. 

So there is a window of opportunity when women's hearts most benefit from HRT.


Clot risk

The only statistically significant negative finding from the WHI trial was an increased risk of blood clots (in the leg or lung).

This is because they were using oral estrogen.

Just like the combined pill, oral estrogen in HRT carries a small increased risk of clots - so it cannot be used by women with a history of clots or who are at high risk of having clots. 


There is no increased clot risk with transdermal estrogen


Transdermal estrogen (which means estrogen that is given through the skin in the form of a patch or gel) does NOT carry this increased risk of clots. There are even studies that have shown it can be safe for women with genetic conditions that make them more at risk of clots. 


What the WHI never told us...

Apart from the over-exaggerated risks, the other really sad thing about the WHI press conference in 2002 was all the findings that never made the headlines. 

Women on HRT were less likely to have osteoporosis, fractures, diabetes and bowel cancer.

Those on estrogen-only HRT were less likely to have breast cancer.

But most importantly -


Women starting any type of HRT before the age of 60 were less likely to die from any cause, including breast cancer.


These are the facts about HRT that every woman (and doctor) should know.


What has changed since the WHI?

We now have body-identical/bio-identical HRT.

The type of HRT used in the WHI trial was not body-identical.

We also tend to use transdermal estrogen (as a patch, gel or spray) which removes the small increased clot risk seen with oral forms of estrogen. 

The progesterone part of HRT has also improved - we now have body-identical progesterone and this has been shown to have even lower risks of breast cancer than regimes using synthetic progestins. 


Working out the risks with HRT

You can use this online tool below to see for yourself what the data says about risks and benefits with HRT.


WellSpring Health Infographic Tool


It has been created by consultant doctors in the UK to summarise all the available evidence about HRT benefits and risks.

You can select different types of HRT regimes on the left hand side menu.

Across the top, you can select either the 'Benefits' or the 'Risks'

You can then choose either '5 years of HRT' or '10 years of HRT'

The pink colour shows you how many women per 100 will get those diseases every year, unrelated to HRT use. This is the background risk. 

When you toggle the 'with HRT' switch under each category, the green colour shows you how many additional women will get those same diseases as a result of taking HRT.


How does HRT compare to other risk factors for Breast Cancer?


Click on the link below from the British Menopause Society to see more about different risks for breast cancer here:


Understanding the risks of Breast cancer 



Boardman HM, Hartley L, Eisinga A, et al. Hormone therapy for preventing cardiovascular disease in post-menopausal women. Cochrane Database Syst Rev. 2015;(3):CD002229.

Canonico M, Carcaillon L, Plu-Bureau G, et al. Postmenopausal hormone therapy and risk of stroke: impact of the route of estrogen administration and type of progestogen. Stroke. 2016;47(7):1734-1741.

Crandall C, Hovey K, Andrews C, et al. Breast cancer, endometrial cancer, and cardiovascular events in participants who used vaginal estrogen in the Women’s Health Initiative Observational Study. Menopause. 2018;25(1):11-20.

LaCroix AZ, Chlebowski RT, Manson JE, et al; WHI Investigators. Health outcomes after stopping conjugated equine estrogens among postmenopausal women with prior hysterectomy: a randomized controlled trial. JAMA. 2011;305(13):1305-1314.

Laliberte F, Dea K, Duh MS, Kahler KH, Rolli M, Lefebvre P. Does the route of administration for estrogen hormone therapy impact the risk of venous thromboembolism? Estradiol transdermal system versus oral estrogen-only hormone therapy. Menopause. 2011;18(10):1052-1059

L’Hermite M. HRT optimization, using transdermal estradiol plus micronized progesterone, a safer HRT. Climacteric. 2013 Aug; 16 suppl 1: 44-53

Manson JE, Chlebowski RT, Stefanick ML, et al. Menopausal hormone therapy and health outcomes during the intervention and extended poststopping phases of the Women’s Health Initiative randomized trials. JAMA. 2013;310(13):1353-1368.

Manson JE, Aragaki AK, Rossouw JE, et al; WHI Investigators. Menopausal hormone therapy and long-term all-cause and cause-specific mortality: the Women’s Health Initiative randomized trials. JAMA. 2017;318(10):927-938.

Mueck AO. Postmenopausal hormone replacement therapy and cardiovascular disease: the value of transdermal estradiol and micronized progesterone.
Climacteric. 2012 Apr; 15 Suppl 1:11-7.

Renoux C, Dell’aniello S, Garbe E, Suissa S. Transdermal and oral hormone replacement therapy and the risk of stroke: a nested case-control study. BMJ. 2010;340:c2519.

Straczek C et al. Prothrombotic mutations, hormone therapy, and venous thromboembolism among postmenopausal women: impact of the route of estrogen administration. Circulation. 2005 Nov 29; 112 (22): 3495-500.

Stute P, Wildt L, Neulen J. The impact of micronized progesterone on breast cancer risk: a systematic review. Climacteric. 2018 Apr; 21 (2): 111-122.