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HRT Fact Check

Updated: Jun 14

The HRT breast cancer risk talk has been rumbling for over 20 years, but there's hope that the 'facts' about HRT are soon going to change radically. There are a number of capable and enthusiastic organisations like The Menopause Charity founded by the menopause champion, Dr Louise Newson is funding PhD students and collaborating with experts all over the world to bring more up-to-date evidence of the safety and efficacy of HRT.

Until then, we can go by what we know. We know that with the use of synthetic progestogen, which is usually given with estrogen to protect the lining of the womb, there is a small risk of breast cancer. And we know that although there is an increase in the risk of breast cancer in these women, there is no increase in death. We know this risk of breast cancer associated with synthetic progestogen is much smaller than the risk of having a BMI greater than 30.

We know that body-identical progesterone (e.g Prometrium/Utrogestan) has been found to have no increase in the risk of breast cancer for the first 5yrs of use and for those that use it longer than 5yrs, the risk is not much more.

As doctors, we can invite our patients to look further, if they wished, and bring any questions back to us. In my experience when women are empowered with access to evidence-based information, they will want to know more. They will then go to their doctors with their factual information. The doctors may not be familiar with the facts presented to them by their patients. However, the doctors are driven to look deeper at current evidence. In the process, the doctor as Onora O'Neill says gains trust through their demonstration of trustworthiness!

Mark Twain, "Education is the path from cocky ignorance to miserable uncertainty"

#1. Am I too young for HRT?

Answer: No, you are NOT too young to start HRT.
Although HRT is not licensed for Perimenopause, it works quite well and it makes sense to consider hormones in this age group. When perimenopausal women are given HRT, it is to top up their declining sex hormones. Perimenopause occurs in our 40s and may last for 4 months to 10 years. During perimenopause, we experience significant fluctuations in our hormones (estrogen, progesterone and testosterone). The hormone decline is due to our ovaries slowing down and producing less hormones. Over time, these hormones continue dropping and remain forever low, this is menopause. Due to sharp ups and down in our estrogen, progesterone and testosterone, it is thought that perimenopause is a particularly harsh period of time for a woman. We may experience abdominal weight gain, mood swings, sweet cravings or at times savoury cravings, brain fog, joint and muscle pains and low libido. There are many other hormone decline symptoms. The Australasian menopause society score below highlights some of the symptoms.
In addition, 1/100 women experience menopause (stop having periods and experience menopause symptoms) below age 40, 1/1000 below age 30 and 1/10,000 below age 20. This is called POI (premature ovarian insufficiency) These women will benefit from HRT at least until the natural age of menopause which is 51yrs.
The Daisy Network charity is a great resource for POI.

#2 Am I too old to start HRT?

Answer: No, you are not too old to start HRT
The earlier a woman with symptoms suggesting hormone decline or deficiency gets access to assessment and consideration for HRT the better her current and future health outcome. Research shows that if a woman gets HRT within 10 years of her last period or menopause symptoms starting, her cardiovascular health outcome is better than a woman who starts HRT more than 10yrs after menopause. If you are more than 10yrs after menopause, you may not get a great modification in your blood pressure for example, but other factors like unwanted abdominal fat and weight gain, sleep disturbances, anxiety, depression, joint pain and treating or preventing osteoporosis are improved. You will need to speak to an experienced menopause doctor to discuss starting HRT if you are more than 10yrs after menopause.

Cardiovascular disease (CVD) is a general term for conditions affecting the heart or blood vessels. It's usually associated with a build-up of fatty deposits inside the arteries (atherosclerosis) and an increased risk of blood clots. It can also be associated with damage to arteries in organs such as the brain, heart, kidneys and eyes.

According to the World Health Organisation (WHO), cardiovascular diseases (CVDs) are the leading cause of death globally. An estimated 17.9 million people died from CVDs in 2019, representing 32% of all global deaths. Of these deaths, 85% were due to heart attack and stroke. Out of the 17 million premature deaths (under the age of 70) in 2019, 38% were caused by CVDs. Most cardiovascular diseases can be prevented by addressing behavioural risk factors such as tobacco use, unhealthy diet and obesity, physical inactivity and harmful use of alcohol.
A holistic approach is therefore necessary. HRT is not a magic bullet for preventing CVD, addressing lifestyle choices that increase our risk of CVD works together with HRT to keep our health.

#3 Does Estrogen cause breast cancer?

Answer: No, estrogen does not cause breast cancer.
Women followed up in the famous WHI (Women Health Initiative) study has shown that Among postmenopausal women on hormone therapy, there is no increase in the risk of death from all causes. Neither is there an increase in the risk of cardiovascular disease or cancer during the 18-year follow-up. Women who have had a hysterectomy, only need estrogen replacement and if necessary testosterone. Women without a hysterectomy should have progesterone, in addition to estrogen. The synthetic progestogen given to women who have not had a hysterectomy has a slight increase in the risk of breast cancer.

#4 Tell me more bout the slight increase in breast cancer with synthetic progestogen

Synthetic progestogen has been shown to have a slight increase in the risk of breast cancer. But the body-identical progesterone (micronised progesterone) has been found to have no increase in the risk of breast cancer for the first 5yrs of use and for those that use progesterone for more than 5yrs, the risk is not much more.
The small increased risk of breast cancer in women who take HRT is related to the type of progestogen in the HRT. Taking Prometrium (Utrogestan in the U.K) does not appear to be associated with an increased risk of breast cancer for the first five years of taking it. After this time, the risk of breast cancer is very low; studies have shown the risk to be lower than the risk for a woman taking the older types of progestogens.
Even for women taking the older types of progestogen, the risk of breast cancer is very low. The level of increased risk with the older types of progestogen is similar to the level of risk of breast cancer in women who are overweight, or women that drink around two glasses of wine every day.

#5 : Why then do doctors tell us that HRT increases the risk of breast cancer?

A ‘great divide’ exists between what is real and what is not in the perception of the risks and benefits of HRT.
According to a review published in Climacteric, the journal of the International Menopause Society, the threat that women may develop breast cancer is the major reason why both doctors and women are ‘afraid’ to use HRT. This paper looked at the way breast cancer risk with HRT was reported in major publications since 2002. in 2002, the Women’s Health Initiative study (WHI) was stopped amid concerns of an increased risk of breast cancer and cardiovascular disease in women who took combined HRT. However, in the WHI study, women used an older estrogen and older progestogen that is less commonly prescribed now, they were on average 63 years old, and many were obese and had had heart attacks in the past. However, further analysis of this study has shown that the risks are really low or not present.

In the wake of the WHI study, HRT users fell from two million to less than one million in the UK between 2003 and 2007. This decline was reflected globally. Estimates from Australia in 2013–2014 have reported the current use of HRT/MHT in women in their 50s and 60s to be around 12–13%.

Tan and Dayu (Authors of the above review) of the department of obstetrics and gynecology at St Luke’s Medical Center Quezon City, the Philippines did a review of all the current research findings relating to HRT. The aim of the review was to put the 'HRT use–risk' association in context.
They suggest five reasons why doctors and women should no longer be afraid of breast cancer risk with combined HRT.
These are:
• That breast cancer related to combined HRT use is rare because the risk is very low
• The reported increase in breast cancer risk when taking combined HRT is not related to the current practice of prescribing Body identical HRT
• Modifiable lifestyle factors, not combined HRT, are the real risks for breast cancer
• Breast cancer-specific mortality is reduced in women who develop breast cancer while taking combined HRT
• Avoiding HRT use when indicated puts a woman in harm’s way as there are risks (such as the increased risk of heart disease and osteoporosis) of avoiding HRT. Estrogen alone does not increase the risk of breast cancer. Women with a hysterectomy only need estrogen. Unlike tablet estrogen, estrogen as a gel or patch has no increase in the risk of blood clots or stroke and heart attacks.
For more evidence-based podcasts and all things, menopause visit balance-menopause. Download the balance menopause app to track your symptoms, get evidence-based information on menopause management and connect with other menopausal women all over the world.

Dr Purity Carr is a GP and Menopause Doctor in Harvey, Western Australia
Don't forget to ask me your questions!


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