Increased Asthma Risk With HRT

Research in France and Denmark has shown HRT could significantly increase women’s chances of having asthma attacks severe enough to put them in hospital.


You may think that asthma has nothing to do with your hormones, but you would be wrong. The severity of asthma attacks does vary throughout the menstrual cycle and during pregnancy, but the incidence tends, in general, to fall after menopause. However Danish scientists beg to differ.

HRT Risk increases over time

Unlike some recent HRT research which claimed benefits on a trial of just 6 sets of twins, this study has looked at a large group of women. Researchers at the Danish Paediatric Asthma Centre and Danish Cancer Society looked at the records of more than 23,000 women, noting whether they were prescribed HRT and for how long, and if they had ever needed hospital treatment for an asthma attack.

What they found was something of a surprise in that it was clear that the longer a woman was on HRT, the more the risk increased:

  • 29% more likely to go to hospital if on HRT for up to 3 years
  • 34% higher risk for those taking it for more than three years
  • 50% more likely to need treatment if on it for more than ten years


“the drugs may not only trigger asthma in those who have never suffered from the condition, but also make their symptoms far worse.”

They are so concerned by the findings that they have called for doctors to stop prescribing the treatment to any patient who complains of breathing problems. The possibility of a link between HRT and asthma was reported also last year when a 12-year study of more than 58,000 women in France found that those receiving oestrogen-only replacement therapy were 54 per cent more likely to develop the condition.

However, the latest study marks the first time that HRT has been shown to put patients at risk of having a serious attack that requires hospital treatment.

Dr Klaus Bønnelykke from the DPAC said: ‘Previous research has suggested a link between asthma and female sex hormones, especially HRT. Our findings extend this to severe asthma exacerbations. If a patient develops asthma or has a severe worsening of symptoms after taking HRT, they may need to stop hormone therapy altogether.’

Time to switch?

The health problems associated with HRT are well known and include increased risk for cancer and heart disease and this is why an increasing number of women switch to a more natural form of HRT with bioidentical hormones.

HRT use has dropped dramatically since 2002 so that now only 1 in 10 eligible women use it. That still means that around 150,00 in the UK are currently being given HRT.

The benefits of bioidentical HRT are not as well known, but certainly appreciated by the many women who have switched. Whether that is to progesterone only to combat excess oestrogen, or to a combination of progesterone and natural oestrogens to help after a hysterectomy or with the more severe symptoms of menopause.

Menopause cannot be avoided, but the symptoms of hot flushes, night sweats, mood swings and depression certainly can be helped and without running the risk of the synthetic hormones found in HRT.