When added to conventional hormone replacement therapy (HRT), testosterone may reduce the risk of breast cancer in postmenopausal women, results of a small study suggest. “I hope that this paper stimulates interest in the question of whether a more physiological HRT regimen might have better effects,” senior author Dr. Carolyn A. Bondy told Reuters Health. But, she emphasized, “I do not recommend any changes in HRT treatment until we’re convinced it’s safe and efficacious.” The Women’s Health Initiative and the “Million Women” Study, large clinical trials of combined estrogen and progestin HRT, were terminated early when they showed an increased risk of breast cancer. However, these studies did not evaluate combined treatment that included testosterone. Bondy, with the National Institutes of Health in Bethesda, Maryland, and colleagues report the results of a look-back study of 508 postmenopausal women given testosterone and estrogen, with or without progestin, for an average of about 6 years. Their findings are published in the medical journal Menopause.