article_snippet.sent: In the early 1990s, some smaller studies suggested the therapy would reduce a woman's risk of coronary heart disease and osteoporosis.
article_snippet.sent: But for oestrogen alone, it looks like the hormone may be more favourable in reducing breast cancer risk than we thought before.
article_snippet.sent: 'oestrogen alone are now quite compelling that we may have to call oestrogen alone risk reduction.'
article_snippet.sent: Both found strong evidence the treatment increases a woman's risk of breast cancer, pictured, with the latter finding it doubled a woman's risk .
article_snippet.sent: But the study authors noted: 'Subsequently, breast cancer risk increased throughout the intervention phase and became statistically significant.'
article_snippet.sent: Even up to five-and-a-half years later, breast cancer risk remained high.
article_snippet.sent: In addition, researchers note that at an eight-year follow-up a 'risk reduction was not observed'.
article_snippet.sent: But for those women taking oestrogen only treatment, the risk for invasive breast cancer fell.
article_snippet.sent: However, despite the findings, Dr Chlebowski urged caution.
article_snippet.sent: But it's always difficult to figure out how to categorise the risk for invasive breast cancer,' Dr Chlebowski added. '