How safe is HRT?
The average age of menopause is 51 but symptoms often start many years before this during what is known as the perimenopause. During this time, women often experience symptoms that can range from hot flushes and night sweats to mood swings and achey joints. If you’ve started to experience menopause symptoms, you may have begun to wonder if hormone replacement therapy (HRT) is for you.
There have been countless headlines over the years praising the virtues of this hormonal treatment, and countless others warning of its severe health risks. Here, we cut through the noise and outline what the evidence says about whether HRT is safe to take throughout our 40s, 50s and beyond.
What is HRT and what does it do?
HRT stands for hormone replacement therapy. It’s designed to top up the levels of estrogen, progesterone and, in some cases, testosterone that fall throughout the menopause.
The hormones in HRT are derived from the yam plant and are body-identical. This means they’re molecularly identical to the hormones naturally produced by our bodies.
By replacing declining levels of estrogen, HRT can improve and often eradicate menopause symptoms such as hot flushes, night sweats, reduced libido, joint pains, mood swings, vaginal dryness and urinary incontinence.
HRT has been show to reduce our future risk of cardiovascular disease, osteoporosis, type-2 diabetes, osteoarthritis and dementia. Women who start taking HRT within 10 years of their menopause stand to benefit most from these reduced risks.
What are the risks?
For the vast majority of women, the benefits of taking HRT outweigh the risks.
HRT and blood clots
Blood clots can form in a deep vein (known as deep vein thrombosis) or break of and travel to the lungs (known as a pulmonary embolism) which can be life-threatening.
Many women have been incorrectly told that they cannot take HRT as they have a history (or are at a high risk) of developing a blood clot. While estrogen taken as a tablet comes with a small increased risk of clots, estrogen taken as a patch, gel or spray will not raise our risk.
The same is true of progesterone. While older formulations (known as synthetic progesterone) have been linked with an increased risk of clot, the newer variety (known as micronised progesterone or Utrogestan) is not associated with any increased risk.
Studies show that estogren absorbed through the skin and micronised progesterone do not increase the risk of clot even in those women who are at an increased risk due to cancer, lupus or clotting disorders such as factor V Leiden.
“If your doctor has told you HRT is not safe because you have a risk of clot, this is incorrect information,” says menopause expert Dr Louise Newson. “You could try and see another doctor who is more informed about HRT.”
Breast cancer is a relatively common cancer affecting 1 in 7 women throughout their lifetime. The good news is that survival rates have doubled in the last 40 years.
Some studies show that women taking combined HRT (including both estrogen and progesterone) may be associated with a small increased risk of breast cancer. The increased risk is very small, however. It’s lower than the risk associated with drinking a couple of glasses of wine a night or from being overweight. You can see the associated risks explained clearly in this graphic from Women’s Health Concern.
No studies have shown that any type of HRT increases the risk of a woman’s death from breast cancer. For those taking estrogen-only HRT, there is actually a small reduction in breast cancer risk. There’s no increased risk of breast cancer in women who take any type of HRT when they are under the age of 51.
There’s also no strong evidence that a familial history of the disease puts women at a higher risk if they take HRT when compared with women with no family history of the disease. In fact, there is some evidence that women taking HRT have a lower risk of breast cancer when compared to women not taking HRT. This means that most women (including those with the BRCA gene) can still take HRT safely.
Some women even choose to take HRT after breast cancer treatment once they’ve weighed up the risks and benefits to their future health and quality of life.
HRT and migraine
Migraines are most common in women in their 40s when hormones begin to fluctuate and fall during what is known as the perimenopause. In many women, restoring oestrogen by taking HRT will improve these symptoms.
In some cases, however, HRT can trigger migraines if not properly prescribed. The key is ensuring the type of HRT your doctor prescribes is transdermal estrogen which absorbs through the skin and is unlikely to trigger a migraine.
The oestrogen patch, gel or spray should then be taken continuously, without breaks, to avoid any rapid changes in hormone levels that can cause headaches and auras. It’s best practice to start on a low dose and increase levels very gradually until menopause symptoms disappear.
HRT and weight-gain
Many women wrongly believe HRT causes weight gain. Studies show that women are more likely to lose weight when taking HRT when compared to taking a placebo (dummy pill).
In its 2016 review, the International Menopause Society is clear that HRT ‘is not associated with weight gain and may ameliorate perimenopausal accumulation of abdominal fat.”
This reduction in fat around the middle is due to HRT helping to disperse the ‘middle-aged spread’ (one of the functions of estrogen is to control where our fat ends up being deposited). When our estrogen levels are low, fat accumulates around the tummy — the notorious muddle-aged muffin top. This is one reason why HRT also helps cut heart disease. We know that women whose fat is mostly accumulated around the middle (the so-called apple shape) are more at risk of heart attack and stroke.
What about vaginal estrogen?
Vaginal estrogen is safe to take alongside HRT. About 20% of women need both to treat symptoms such as vaginal dryness, atrophy, incontinence and recurring infections. This can be take as a pessary, cream, gel or vaginal ring and must be used continually for lasting results.
There are no risks associated with this type of HRT and the dose of estrogen is very low. In fact, vaginal estrogen applied regularly for a year adds up to the equivalent dose of just one HRT tablet.
Women with a history of any type of cancer (including an estrogen-receptive cancer) can still safely use this type of HRT.
Find out more about Hormone Replacement Therapy
Download Liz’s guide, The Truth about HRT
Liz’s bestselling e-book uncovers the truth about HRT. The aim of this guide is to give all women affected by menopause symptoms, as well as their medical advisors, the most up-to-date, relevant and helpful information on HRT. You’ll be able to make an informed choice to significantly improve your long-term health and wellbeing.