You started HRT hoping to feel like yourself again. Two weeks in, your breasts are sore, a headache keeps coming back, and you feel more tearful than you did before. It is completely natural to wonder whether these side effects of HRT mean you have made a mistake.
Side effects are the reason many women stop a treatment that might have helped them, often in the first month and often without telling anyone. I understand why. But most side effects are mild, settle on their own, and can usually be fixed by changing the dose, the route or the type of hormone rather than giving up altogether.
These are conversations I have all the time with my patients. A woman tried HRT once, felt bloated or tender or teary, and decided it was not for her. Very often, it simply was not the right preparation yet.
The side effects of HRT are usually your body adjusting
Common early effects include breast tenderness, headaches, nausea, leg cramps, mood changes and irregular spotting. These often go away after a few weeks and we advise carrying on for at least three months if you can before deciding whether a treatment suits you. Most are a sign that your body is adjusting to a change in hormone levels, not a sign that something is wrong.
Why so many different effects at once? Oestrogen acts on receptors throughout the body, including the breasts, brain, blood vessels, bladder, bones and skin. When levels rise after a long period of decline, several of these can respond together.
Many side effects are related to the dose and are short-lived, which is why starting low and increasing gradually is usually better tolerated than starting high. The route matters too. Oestrogen absorbed through the skin, as a patch, gel or spray, bypasses the liver, which changes both how it is tolerated and its risk profile compared with tablets.
Each hormone can affect you in its own way
Oestrogen treats the symptoms of menopause. Possible side effects: headaches, breast pain or tenderness, feeling sick, leg cramps, mood changes including low mood, mild rash or itching, diarrhoea, hair loss, and unexpected spotting or bleeding. Some women also notice bloating or fluid retention, and with patches the skin underneath can become red or irritated. Breast tenderness is often related to the dose, so a lower starting dose or a slower increase frequently eases it. Taking tablets with food can help with nausea.
Progestogen is added if you still have a womb, to protect its lining. This part matters: taking oestrogen without it raises the risk of womb cancer, so please don’t simply drop your progestogen if it disagrees with you. Talk to your doctor first. (I know this can be hard when you feel low or bloated!)
Women respond to progestogens very differently. Possible effects include changes to bleeding, headaches, breast tenderness, nausea, tiredness or dizziness, mood changes or low mood, a rash, acne and a premenstrual-type feeling, particularly with a cyclical regimen. Mood-related effects do not always settle on their own. The good news is that switching to a different progestogen, moving from a cyclical to a continuous regimen where appropriate, or using a hormonal coil often resolves them. Micronised progesterone is often well tolerated. If you have had a hysterectomy, you will usually take oestrogen on its own.
Sometimes the dose itself is the issue. Persistent breast tenderness, nausea or headaches can suggest the oestrogen dose is higher than you need, while continuing hot flushes can suggest it is too low.
Some women are also prescribed testosterone for low sexual desire that persists despite HRT. Most testosterone used in the UK is a men’s product prescribed off-label at a much lower dose. One cream is now licensed for postmenopausal women but is only available privately, not on the NHS. Either way, it is monitored with blood tests.
Bleeding is the effect that worries women most. Irregular spotting or light bleeding is common in the first three to six months of continuous combined HRT while the womb lining settles, and for around three months after any change of dose or preparation. We advise mentioning it at your three-month review, and seeking advice if it carries on for more than six months after starting or becomes heavier.
Side effects and risks are not the same thing
Side effects are what you feel. Risks are about the chance of a health problem over time, and they depend on your age, when you start, your personal and family history, and the type of HRT. So every decision is based on an individual discussion of benefits and risks, and I agree: there is no one-size answer here.
Breast cancer. Combined HRT, with oestrogen and a progestogen, is linked to a small increase in breast cancer risk, which rises the longer it is taken and falls after stopping. Oestrogen-only HRT, for women who have had a hysterectomy, is associated with little or no change in risk. Alcohol, weight and activity also affect breast cancer risk.
Blood clots and stroke. Oestrogen tablets slightly increase the risk of blood clots and stroke. At standard doses, patches, gels and sprays do not raise these risks above those of women not taking HRT, which is why they are often preferred for women with added risk factors.
And weight? There is little evidence that most types of HRT make you put on weight. Weight change in midlife is common whether or not you take HRT, and early fluid retention can make some women feel heavier for a while.
Some symptoms should never wait
Most side effects are not dangerous, but a few need urgent attention:
- Call 999 if you have chest pain, sudden breathlessness, or sudden weakness, numbness, or changes to your vision or speech.
- Get urgent medical advice the same day, from your GP or NHS 111, if you have pain, swelling or redness in one leg, or a sudden severe headache.
- Stop your HRT and see a doctor straight away if you notice yellowing of your skin or the whites of your eyes, swelling of your face, tongue or throat, or hives, signs of a large rise in blood pressure (such as headache, tiredness or dizziness), migraine-like headaches for the first time, or if you become pregnant.
See your doctor promptly if you have bleeding that continues beyond six months, becomes heavier or returns after it had stopped, a new breast lump or change, persistent low mood, or symptoms that are still poorly controlled after three months. Keep attending breast and cervical screening when invited.
Change one thing at a time, and write it down
A great deal can be done without stopping treatment. The approach I recommend is to change one thing at a time, so the effect of each change is clear:
- Adjust the dose. A slightly lower dose, increased more gradually, often eases breast tenderness and headaches.
- Change the route. Moving from tablets to a patch, gel or spray can help with nausea, and is often preferred where there are clotting risk factors.
- Change the progestogen. A different progestogen or a hormonal coil may suit women with mood or premenstrual-type effects.
- Change the regimen. Moving from cyclical to continuous HRT, where appropriate, can reduce monthly ups and downs.
- Check how it is applied. Rotating patch sites, letting gel dry fully and avoiding moisturiser on the area can reduce skin irritation.
To make these changes work, keep a simple note for your first three months. Write down the date you started or changed anything, what you notice and when (for example, “sore breasts in week two” or “headache the day after a patch change”), and your top three symptoms you wanted HRT to help with. Bring it to your review. I promise these small notes add up, and they turn a vague “it doesn’t suit me” into something we can actually fix.
I recommend reviewing your treatment three months after starting or changing HRT, and then once a year. Everyday habits support treatment too: strength training protects bone and muscle, and cutting back on alcohol and caffeine may help with hot flushes and sleep. If you do decide to stop, stopping suddenly is not dangerous, but symptoms may return quickly, and some women find a gradual reduction more comfortable.
A side effect is a reason to adjust, not to give up
You do not have to put up with side effects, and you do not have to abandon a treatment that could help you because the first version did not fit. Many women who believe HRT does not suit them simply have not yet found the right combination.
And if HRT is not suitable for you, because of your health history or because you would rather not take it, that is a valid decision too. You still deserve an individualized plan for your symptoms, and that is exactly what a menopause consultation is for.
Whichever group you are in, the first few weeks are not the final word.
In one unhurried 45-minute consultation at 10 Harley Street, Dr Katy Kasraie will look at your health history, your goals and every suitable option, including approaches that do not involve medication. No referral needed, and most major insurers are accepted. Click here to book your appointment.