Women should not be put off hormone replacement therapy by over-hyped fears about its health risks, a panel of international experts has concluded in a move that is likely to add to public confusion over the safety of HRT.

For women aged 50 to 59 in the early years of the menopause, the hormone treatment is safe and effective, said the scientists - it alleviated menopausal symptoms such as hot flushes and maintained healthy bones without significant harmful side effects.

The experts reported that, contrary to what many people had been led to believe, HRT did not raise the risk of heart disease for these women, and its impact on the risk of breast cancer was "minimal".

Although certain types of HRT containing combinations of oestrogen and progesterone could slightly increase the chances of developing breast cancer, their effect is apparently dwarfed by other risk factors.

Dr David Sturdee, one of the report's authors and president-elect of the International Menopause Society, said medics should be prescribing HRT more freely.

The current advice to health professionals is that HRT should only be offered to women with serious menopausal symptoms for the shortest time possible. After five years, doctors are not expected to continue prescribing the treatment without thoroughly discussing the potential risks with patients.

"We feel women should have it for as long as they need it to maintain their quality of life," said Dr Sturdee, speaking at the Science Media Centre in London yesterday.

Forty experts from around the world took part in a summit in Zurich, Switzerland, to discuss the latest evidence on the health risks. They presented their findings at the World Congress on the Menopause in Madrid.

The scientists said the health hazards of HRT had been blown out of proportion largely because of misleading results from a US investigation.

In 2002, the Women's Health Initiative (WHI) produced data which appeared to show women on HRT were at a heightened risk of breast cancer and heart disease.

It had a major impact, causing large numbers to avoid hormone replacement and convincing many doctors that the treatment was not safe. In Scotland, prescriptions of HRT halved from 609,000 in 2001-02 to 346,000 in 2005-06.

However, the research has been strongly criticised for presenting an unbalanced picture. In particular, researchers were accused of focusing on the wrong group of women. The average age of the study participants was 63, whereas most women start taking HRT 10 years earlier.

In addition, 36% of the women had high blood pressure, 49% were current or past smokers, and 34% were clinically obese.

After reviewing the evidence, the summit experts concluded that combination oestrogen and progesterone HRT did not raise the risk of heart disease in healthy women aged 50 to 59. They also concluded that oestrogen-only HRT, normally reserved for women who have had their wombs removed, cut the risk of heart disease.

The experts found that, while oestrogen and progesterone HRT did slightly increase the risk of breast cancer for women in this group, the effect was minimal compared with other risk factors.

Short to medium-term use of oestrogen-only HRT was not associated with a raised risk of breast cancer.

It was also concluded that HRT effectively maintained bone density in women aged 50 to 59 and could help prevent the brittle bone disease osteoporosis, a recognised symptom of the menopause.

Dr Sturdee, a consultant obstetrician and gynaecologist at Solihull Hospital, said at least a million women in the UK had stopped taking HRT because of unfounded health fears, and suffered as a result.

There were anecdotal reports of doctors imposing a blanket ban on HRT, although that was at odds with guidelines.

"Women's confidence has been shattered," said Dr Sturdee. "They are going to take a lot of convincing that the initial reports weren't a reliable assessment of the data."