Hormone replacement therapy (HRT) is a common treatment for menopause symptoms such as hot flushes, night sweats, sleep problems and low mood. It is generally very safe and highly effective, helping to improve the overall well-being of most women.
It works by both replacing and smoothing out the changes of the hormones that naturally decline during menopause that can give rise to undesirable and often unpleasant changes in your body.
Like any other medication, HRT can cause side effects. It’s common to have no side effects at all when taking HRT or only very mild ones but being aware of the potential side effects can help you to make a fully informed choice about your treatment and ensure you know what to expect.
Is it normal to bleed while on HRT?
In the first few months of starting HRT, it is common to experience spotting or irregular vaginal bleeding. This usually resolves itself within six months and isn’t normally an indication of anything serious.
If you’re prescribed a cyclical/sequential combined HRT regimen, it’s normal to have withdrawal bleeding at the end of the progesterone phase.
Continuous combined HRT commonly results in irregular breakthrough bleeding or spotting in the first 4-6 months of treatment.
You should tell your GP if you’re having irregular bleeding on HRT. If it persists, your dose or type of progesterone may need to be changed.
Common HRT side effects
There are several different types of HRT. Depending on your symptoms and medical history, you may be prescribed oestrogen or oestrogen and progesterone. There are also different ways to take HRT including oral tablets, patches, gel, spray, vaginal cream, rings and pessaries. Each type of HRT has its own list of known side effects.
Side effects of oestrogen
The side effects of oestrogen therapy for menopause can include:
- Spotting and irregular vaginal bleeding
- Headaches
- Breast pain or tenderness
- Nausea (feeling sick)
- Mood changes, which can include low mood and depression
- Vomiting
- Diarrhoea
- Bloating
- Stomach cramps
- Hyperpigmentation of the skin
- Hair loss
- Vaginal itching
- Leg cramps
- Mild skin rash or itching
Side effects of progesterone
The side effects of progesterone HRT can include:
- Spotting and irregular vaginal bleeding
- Headaches
- Breast pain or tenderness
- Nausea (feeling sick)
- Tiredness
- Dizziness
- Mood changes, including low mood and depression
- Acne
- Mild skin rash or itching
Side effects of combined HRT
When taking combined HRT, you may experience side effects from the oestrogen and/or progesterone. These side effects include:
- Irregular vaginal bleeding or spotting
- Headaches
- Breast tenderness or pain
- Nausea (feeling sick)
- Mood changes
- Diarrhoea
- Muscle cramps
- Mild skin rash or itching
- Hives
Side effects of tibolone
Tibolone is another form of HRT. Your body breaks it down to make substances that act similarly to oestrogen, progesterone, and testosterone. It may be recommended if you have problems with Oestrogen/ Progesterone HRT, or for certain menopause changes, but it isn’t generally used as a first line choice of HRT in menopause.
Side effects of tibolone may include:
- Irregular bleeding or spotting
- Breast tenderness
- Stomach or pelvic pain
- Vaginal discharge and/or itching
- Unusual hair growth
Side effects of testosterone
Sometimes, women who are taking HRT will also be prescribed testosterone for menopause symptoms, particularly the feeling of persistent low desire and libido, when this change feels troublesome or unwanted It's usually given as a cream or gel that you rub into your skin. There are often few side effects of testosterone replacement and they are usually reversible when testosterone is stopped but they can include:
- Increased hair growth in the application areas
- Acne
Risks of HRT
Most HRT risks are outweighed by the benefits and the likelihood of serious side effects is very small. However, it’s important to be aware of any potential risks.
Breast cancer
There is a link between HRT and cancer as HRT slightly increases the risk of breast cancer, although the risk is still low. There are approximately five extra breast cancer cases in every 1000 women who take combined HRT for five years. If you’ve previously had breast cancer, taking HRT is not usually recommended.
The longer you take HRT and the older you are, the more the risk increases. However, the risk falls again once you stop taking it.
There is little to no increased risk of breast cancer when taking oestrogen-only HRT, which can be prescribed if you’ve had a hysterectomy.
You can reduce the risk of breast cancer when taking HRT by only using it for as long as you need to reduce your menopause symptoms.
Ovarian cancer
Both oestrogen-only and combined HRT slightly increase the risk of ovarian cancer. When you stop taking HRT, the risk of ovarian cancer reduces.
Stroke
Oral HRT (tablets) slightly increase your risk of stroke. However, the risk is still very low, especially if you’re under 60.
Patches, gel and spray forms of HRT do not increase your risk of stroke.
Blood clots
HRT tablets can also increase your risk of blood clots, although again, the risk is still very low. If you’re already at a heightened risk of blood clots (because you smoke or are overweight, for example), you’ll normally be advised to use HRT patches, gel or spray instead.
This is because these forms of HRT are safer as the oestrogen is absorbed into your bloodstream through the skin, meaning it doesn’t need to be metabolised by the liver.
How long do HRT side effects last?
The side effects of HRT are usually short-lived. Many will go away within a few weeks, and most will disappear within three months of starting treatment as the levels of hormones in your body balance out.
It’s worth persevering with HRT for at least three months to give your body time to adjust. Some people will still experience side effects after this time but if the side effects of HRT outweigh the alleviation of menopause symptoms, then you should speak to your doctor about your options.
Alternatives to HRT
If the side effects of HRT are impacting your well-being, then you may want to explore alternatives. There are a variety of herbal remedies for menopause symptoms, although research on their effectiveness is often limited. There are also various lifestyle changes that can help you cope including:
- Taking regular exercise
- Eating a balanced menopause diet
- Wearing loose, comfortable clothing
- Improving your sleep hygiene
- Quitting smoking
- Reducing caffeine, alcohol and spicy foods
- Using vaginal lubricants or moisturiser
Cognitive behavioural therapy for menopause symptom management is also highly effective and can be used alongside other holistic approaches such as yoga, mindfulness and meditation.
When to see a doctor about HRT side effects
Knowing when to seek help isn’t always easy, especially as the side effects of HRT can sometimes be hard to tell apart from menopause symptoms.
If you’ve recently started HRT but are experiencing side effects, try to allow three months in total for your body to adjust. However, if your side effects are severe or persist after three months, it is a good idea to review your regimen with a specialist to see if there are some small changes that can be made.
At Menopause Care, we have a wealth of experience in helping women navigate this transitional life stage. We can discuss your current circumstances, review your HRT prescription and advise you on the best next steps. To get started, book a consultation with a menopause doctor.