This project will be based on three studies over a period on three years. The first study is a dose response study that includes 30 breast cancer survivors. They will receive a total of 5 laser treatments with 4-6 weeks intervals The second study is a double-blind randomized controlled trial, that includes 60 breast cancer survivors. 30 of those will receive active intervention and 30 will receive placebo laser treatment and act as controls. Based on the results of the dose response study, a treatment consists of three to five laser treatments every 3 weeks. The third and last study is a one-year follow-up on study two. The conditions are evaluated before and after each treatment by questionnaires, vaginal fluid pH values, punch biopsies and vaginal and urine microbiome. The studies is conducted at the Department of Obstetrics and Gynaecology at Randers Regional Hospital in collaboration with Department of Obstetrics and Gynaecology and Department of Oncology at Aarhus University Hospital.

Inclusion Criteria:

• Breast cancer survivor in endocrine therapy
• Symptomatic genitourinary symdrom of menopause with vaginal discomfort and/or dyspareunia
• Able to read and understand Danish
• Able to give written informed consent

Exclusion Criteria:

• Pelvic organ prolapse ≥ stage 2 according to the Pelvic Organ Prolapse Quantification staging system
• Use of non-hormonal/hormonal vaginal therapies (1 and 12 months prior to the baseline visit, respectively)
• Use of Chemotherapy (6 months prior to the baseline visit)
• Acute urinary tract infection or active genital infection
• History of vaginal reconstructive surgery