By Olivia Henry, the Australian Science Media Centre

Use of menopausal hormone therapy, often called hormone replacement therapy (HRT), has been declining in recent years due to safety concerns, but a recent study of more than 800,000 Danish women has found the therapy is not linked to an increased risk of death.

The findings support current guidelines, which recommend hormone therapy for women who have recently begun menopause and have moderate to severe symptoms, such as hot flashes, disturbed sleep, mood swings, and depression.  

Researchers at Copenhagen University Hospital Herlev in Denmark tracked women from their 45th birthday and followed them for around 14 years, also noting their age, number of children, education, income, country of birth, and health conditions such as diabetes, high blood pressure, and heart disease.

While initial data suggested the risk of death was higher for women who had used menopausal hormone therapy, when they accounted for these other factors, the higher risk disappeared, and the authors found no meaningful difference.

The AusSMC spoke to Aussie researchers who say the findings could be welcome news for the 80% of Australian women who experience menopause symptoms, which can often last around seven years, sometimes even longer.

Dr Mia Schaumberg from the University of the Sunshine Coast said that safety concerns have led to a decline in hormone replacement therapy for menopause in Australia, “even though it can help with a wide array of menopause symptoms that can significantly impact women at mid-life.”

“Indeed, recent data from Australia suggest that less than one quarter of women experiencing menopause symptoms use HRT,” she said.

Dr Amy Dwyer from Adelaide University agreed, telling the AusSMC the study “provides reassuring real-world evidence that appropriately prescribed hormone therapy does not increase a woman’s overall risk of death.”

The study, while promising, is observational, meaning it can’t establish a cause-and-effect, just that there is an association. The results also do not point to a one-size-fits-all approach, as the study excluded many women in high-risk groups.

The study also did not provide any data on smoking or weight, according to Professor Susan Davis AO at Monash University.  

“While the authors adjusted their analyses for a large number of characteristics, these critical factors that influence life expectancy were not included,” she said.

Dr Schaumberg added that many other women with “significant medical history”, such as blood clots and some cancers, were also excluded.

“So the results may not be applicable to people with this medical history,” she said.

Dr Dwyer – who specialises in how hormones interact with breast cancer – agreed, adding not all hormone therapies are created equal, and for high-risk individuals, this might still be a factor for medical professionals to consider when prescribing.

“Emerging data suggest that not all progestins are biologically equivalent, and breast cancer risk may vary by formulation rather than by hormone therapy per se.”

“The key message is nuance: hormone therapy is not one uniform entity, and individual risk depends on timing, indication, and the specific hormones used," she added.

You can read the full AusSMC Expert Reaction here.

This article originally appeared in Science Deadline, a weekly newsletter from the AusSMC. You are free to republish this story, in full, with appropriate credit.

Contact: Olivia Henry

Phone: +61 8 7120 8666

Email: info@smc.org.au