Can I take hormone therapy if I have had a thrombosis, or have high blood pressure or excess weight? When it is possible and which route to use

It depends on which of the three situations applies to you and, above all, on the route. With high blood pressure or excess weight, menopausal hormone therapy (MHT) can usually be considered, and European guidelines prefer transdermal oestrogen, which is absorbed through the skin. A previous thrombosis is different. It is a strong contraindication to the oral route, and in Spain the summaries of product characteristics (SmPCs, known as fichas técnicas) for oestradiol patches contraindicate them if the thrombosis is active or was idiopathic, meaning it had no known cause.

The underlying reason is that hormone therapy is not one product with one risk. It helps to understand what changes from one form to another before looking at each situation separately.

Why the route of administration changes the risk

The 2022 position statement of the North American Menopause Society (NAMS) sums it up like this: the risks of MHT depend on the type of hormone, the dose, the duration, the route of administration, when it is started and whether or not a progestogen is added. According to the same document, the transdermal route and lower doses may reduce the risk of venous thromboembolism and stroke.

NAMS also sets out the general picture: in most healthy women with symptoms who are under 60 or within 10 years of the menopause, the benefits outweigh the risks. When there is a thrombosis, high blood pressure or excess weight, that balance has to be worked out more carefully and the route stops being a minor detail. If you want the full picture, we have an explainer on menopausal hormone therapy, who it is for and its real risks.

If you have had a thrombosis

Venous thromboembolism (VTE) covers deep vein thrombosis, a clot in a vein, usually in the leg, and pulmonary embolism, when that clot travels to the lung. It is the risk of hormone therapy where the difference between routes shows most clearly.

The key study is by Vinogradova and colleagues, published in the BMJ in 2019. It compared 80,396 women who had had a VTE between 1998 and 2017 with 391,494 women who had not. Oral MHT was associated with a 58% higher risk of VTE (odds ratio 1.58).

Not all oral combinations behaved the same way, either. Conjugated equine oestrogens with medroxyprogesterone acetate carried the highest risk (OR 2.10), and oestradiol with dydrogesterone the lowest (OR 1.18). This is why people talk about more modern formulations, using hormones identical to the body's own. We explain this in oestradiol and micronised progesterone: what modern hormone therapy looks like.

In that study the transdermal route showed no increase in VTE risk (overall OR 0.93; 95% confidence interval 0.87 to 1.01), and the result held across different doses and regimens. The European Menopause and Andropause Society (EMAS) points out an important caveat: randomised trials confirm more VTE with the oral route, but there are no randomised trials of transdermal oestrogen. The evidence suggesting it does not increase the risk comes from observational studies and meta-analyses. That does not mean the risk is zero.

On that basis, EMAS considers a personal or family history of VTE a strong contraindication to oral MHT, while transdermal therapy can be considered after an individual assessment. In Spain the framework is stricter: the SmPCs for oestradiol patches authorised by the Spanish Agency of Medicines and Medical Devices (AEMPS), such as 59154, contraindicate their use if there is an active VTE or if there was an idiopathic VTE, with no apparent trigger. An episode with a clear cause is a different situation, and it is for the doctor to assess it with your full history in front of them.

If you have high blood pressure

Hypertension on its own does not rule out hormone therapy. The EMAS Menopause Essentials 2026 document states that there is no evidence that MHT with oestradiol causes or worsens hypertension, and that it can be taken alongside blood pressure medicines. Even so, in women with hypertension it considers transdermal oestrogen preferable.

There are two reasons for that preference. One is an observational study presented at the American Heart Association: women aged 45 or over taking oral oestrogens developed hypertension more often than those using patches, gels or vaginal oestrogens. This shows an association, not cause and effect, and we have not been able to verify the exact figure in the original publication. The other is stroke: according to EMAS, MHT may carry a small increase in stroke risk, which is greater with oral than with transdermal oestrogen. In a woman with high blood pressure, who already has a higher cardiovascular risk, that distinction carries weight.

If you are overweight or living with obesity

Here the recommendation is the clearest of the three. In its position statement on MHT and venous thromboembolism, EMAS states that in women who are overweight or living with obesity and need hormone therapy, transdermal oestrogen should be the first choice. The reasoning follows the same logic as with thrombosis: if there is already a factor adding to the risk, you choose the route that, on the available data, does not increase it further.

So excess weight does not exclude treatment. What it does is guide the choice of route and, sometimes, of dose.

What is assessed before deciding

In any of these three situations, the decision depends on the individual case. A consultation will usually go over these points:

• Whether there has been a thrombosis, in you or a close family member, when it happened and whether it had an identified cause, such as surgery or immobilisation, or was idiopathic.
• How your blood pressure is and what treatment you take to control it.
• Your weight and other cardiovascular risk factors, including any previous stroke.
• Your age and how long it has been since your last period.
• Whether you need a progestogen, because you still have your womb, and which one suits you best.
• Which symptoms you want to treat and whether there are reasonable alternatives.

When hormone therapy is not an option, there are other routes. For hot flushes there are non-hormonal options such as fezolinetant (Veoza), a non-hormonal tablet for hot flushes, which has its own indications and precautions. And the assessment can be done remotely, as long as it is done rigorously. We explain how menopause treatment via telemedicine works in Spain and the rules that govern it.

Key points to remember

With high blood pressure or excess weight, hormone therapy can usually be considered, and the transdermal route is preferred. After a previous thrombosis the oral route is practically ruled out, and in Spain the transdermal route is also contraindicated if the thrombosis is active or was idiopathic. In Spain today you can receive menopause treatment with a prior medical assessment, a prescription from a registered doctor when it is indicated, and ongoing follow-up, which is how we work at AiON. If you want to know what options you have given your medical history, you can check in a few minutes whether treatment is right for you.