Quels sont les signes que le THS ne fonctionne plus ?

During menopause, many women experience a range of challenging symptoms that can make life difficult, such as hot flushes, night sweats and low mood¹.

Thérapie de remplacement hormonal (TRH), used to treat these symptoms, has been beset with issues over safety and side-effects¹. However, NICE advise this is now the gold-standard treatment for menopause. In 2020, a study in the British Medical Journal suggested HRT use is associated with very small increased risks of breast cancer with no increase in breast cancer for those on oestrogen only HRT². HRT can be an effective means of alleviating unpleasant symptoms of menopause³.

Although HRT can vastly improve quality of life for many women, it is not uncommon for menopausal symptoms to re-emerge after it has been used for several years.

Why menopausal symptoms may return

During périménopause and early menopause the ovaries still produce a small amount of oestrogen and some will also be produced by fat throughout the body. It is the fluctuation and eventual decline of oestrogen at menopause that causes troublesome issues. HRT replaces the body's natural oestrogen, therefore reducing symptoms.

A progestogen hormone is also given with oestrogen in combined HRT to protect the womb, so that the lining doesn't become too thick and cause cancer de l'endomètre. This is not needed if you have had a full hysterectomy, for example.

Dr Heather Currie, an associate specialist gynaecologist at Dumfries and Galloway NHS, and past Chair of the British Menopause Society, says: "The general recommendation is to start on a low-dose preparation and often that will be enough to top up the levels."

A few years down the line, the ovaries will produce less oestrogen and this may lead to a recurrence of symptoms.

"Some women may think their HRT isn't working anymore, but it's doing what it has always been doing," says Currie. "It's just that the total amount of oestrogen in your system may be less. That's quite a common reason for recurrence of menopausal symptoms and you may need to up your dose of HRT."

Dr Tina Peers, a menopause specialist at Chelsea and Westminster Hospital Menopause Clinic, agrees:

"A return of night sweats, flushes, not sleeping and so on is very indicative that your hormones are not quite in balance."

How do I know my HRT needs increasing?

Dr Peers recommends all her patients have a blood test once a year as part of an annual review to see where their oestrogen is at and whether an HRT adjustment is required."

However, Currie points out that blood tests to measure hormone levels are not always considered necessary in managing HRT dosage and are not standard GP practice.

As we age, other health issues may have similar symptoms to those of menopause. It is important to be aware of conditions such as type 2 diabetes and une maladie cardiaque, and to consider whether the thyroid gland and liver are functioning normally.

Lifestyle issues, including weight gain, an unhealthy diet, alcohol and caffeine consumption, smoking and niveaux de stress, can also trigger a return of menopausal symptoms.

"It's worth examining if any of these factors have changed and may be having an impact, rather than immediately increasing the dose of oestrogen," explains Currie.

As your ovaries produce less oestrogen over time, you may require a higher dose of HRT, but also a different delivery method.

Currie says: "Sometimes women use an oestrogen-only patch and take progestogen tablets separately, or a Mirena coil intrauterine system can be used at this stage, which will put the progestogen directly into the womb." This is the gold-standard management for menopause.

Upping your oestrogen in patch form does not appear to increase the small risk of breast cancer associated with HRT use, but if you increase it orally, there is a deep vein thrombosis risk that may be a concern, says Currie.

Peers is also inclined towards transdermal delivery (patches or gels) rather than tablets for this reason. Transdermal HRT does not increase your risk of deep vein thrombosis or stroke so is safer to use.

"It's worth noting though that women vary in how they react to HRT and in absorption of hormones through the skin. I was using one brand of HRT gel and my levels dropped but when I switched to another brand it absorbed and levels went up, so it is worth experimenting and finding what works for you."

When women say they're 'through' menopause, they mean they've moved through the early fluctuating symptoms such as flushes, sweating, joint aches and mood changes.

"This initial phase - caused by falling oestrogen levels - may last a short time, or a long time or be hardly noticeable, but the average duration is thought to be about seven years or so," says Currie.

HRT does not delay menopause, but controls symptoms while they are present. In time, some women come off HRT and don't experience a return of the early menopausal symptoms they had, or the symptoms are far less severe.

Currie adds: "This is because the effects of oestrogen deficiency change according to what stage we're at. Women may need their oestrogen dosage adjusted at certain points when on HRT, but just because they move to a higher dose, that doesn't mean they will need to stay on a high dose ongoing. Oestrogen drops to a certain point and stays there - it doesn't keep dropping as we age."

There are other menopausal changes that HRT also helps. Vaginal atrophy and associated bladder symptoms - and the effects on bone density - are all menopausal changes that occur as oestrogen drops.

"Vaginal atrophy and bladder issues caused by a lack of oestrogen may need ongoing management," says Peers. "Using pH-balanced lubricants, intra-vaginal probiotics and low-dose vaginal oestrogens - creams or pessaries - may help maintain vaginal health at menopause."

Your GP may be able to adjust your HRT dosage or refer you to a consultant for advice and management. Some hospitals offer specialist menopause clinics and the British Menopause Society can help you find a menopause specialist in your area. La Ménopause, ça compte is another great resource.

Can you still have menopause symptoms while on HRT?

For many women, finding the right dosage of HRT for them is enough to relieve their menopause symptoms. However, this isn't always the case, as many factors can affect how well HRT works. For example, other health conditions, lifestyle changes, and human error may cause menopause symptoms during treatment. If HRT isn't improving your day to day life, speak to your doctor.

1. National Institute for Health and Care Research, Le risque de cancer du sein avec le THS dépend du type de thérapie et de la durée.

2. British Medical Journal, Study provides new estimates of breast cancer risks associated with HRT.

3. National Institute for Health and Care Excellence, Menopause: Diagnosis and management.