摘要： Objectives: To assess the effects of vaginal erbium laser treatment on the vaginal health and sexual function of postmenopausal women with a history of breast cancer. Methods: An open, prospective, therapeutic intervention study was conducted with 24 postmenopausal women with a history of breast cancer and vaginal dryness, and/or dyspareunia, who had not used vaginal hormone therapy for at least 6 months. The women were treated using a 2,940-nm Erbium: YAG laser (Etherea-MX, Athena, Sa?o Carlos, Sa?o Paulo, Brazil), with 90o and 360o scanning scopes, between August, 2017 and October, 2017 in a private clinic in a city of southeastern Brazil. Vaginal erbium laser treatment was performed at three sessions with a 30-day interval between each session. Sexual function was assessed before and 1 month after treatment using the Short Personal Experiences Questionnaire. Questions related to genitourinary symptoms were also applied. Vaginal health was assessed before each laser session using the Vaginal Health Index Score. Results: Mean age was 53.7 years. Vaginal health improved, as shown by an increased overall score (P < 0.001). The effect size was large between pretreatment and post-treatment scores for vaginal elasticity, fluid volume, epithelial integrity, and moisture. The effect size was also significant for the overall sexual function score and for the score in the dyspareunia domain between pretreatment and 1 month after the final treatment session. Conclusion: Vaginal erbium laser may represent a novel therapeutic option for improving vaginal health and sexual function in postmenopausal women with a history of breast cancer.