WOMEN on hormone replacement therapy may still not be getting enough oestrogen to prevent brittle bone disease, doctors from Llandough Hospital, South Glamorgan, warn in the British Medical Journal. They say that the oestrogen content of certain HRT preparations is below the dose thought most effective in preventing the disease.

In a review of HRT prescribing in South Glamorgan involving 2,170 patients, the doctors found that 37 per cent of women on HRT were receiving doses of oestrogen below the level most effective in preventing the onset of osteoporosis. Dr David Clements, senior registrar at the hospital, said that HRT preparations with low dosages of oestrogen might stop menopausal symptoms but could not be guaranteed to prevent bone loss. Many GPs were conservative in their prescribing habits and chose the lowest dose anyway, he said.