Recently, two major epidemiological studies found that hormone replacement therapy (HRT) in postmenopausal women increased the risk of breast cancer. One of the studies also found that HRT increased the risk of cardiovascular disease and thrombosis. As a consequence, women were advised to cease this therapy.

However, detailed analysis of these studies suggests that the conclusions may be erroneous. Other studies suggest that the timing of initiation of HRT for healthy women is critical to achieving a beneficial outcome.

When begun within 5 years of menopause in healthy women, oestrogen-based HRT results in far greater benefits than adverse outcomes.

There is substantial objective evidence that the benefits of HRT include:

The adverse effects of HRT include: