Rationale and design for fractional microablative CO laser versus photothermal non-ablative erbium:YAG laser for the management of genitourinary syndrome of menopause: a non-inferiority, single-blind randomized controlled trial.

Genitourinary syndrome of menopause (GSM) is a common condition affecting up to 50% of postmenopausal women and up to 70% of postmenopausal breast cancer survivors. GSM is a chronic condition with a significant impact on sexual health and quality of life. The mainstay of treatment has been with symptomatic relief using topical emollients or lubricants. Second-line treatment is with topical vaginal estrogens to restore the physiology of the vaginal epithelium. For some, the latter is not suitable or acceptable. Newer treatments with ospemifene and vaginal lasers have now been introduced. The two main types of laser currently used for the treatment of GSM are the fractional microablative CO laser and the non-ablative photothermal erbium:YAG laser. We present a study protocol for a multicenter, prospective, non-inferiority, single-blinded, randomized controlled trial comparing the fractional microablative CO laser versus the photothermal non-ablative erbium:YAG laser for the management of GSM. We will recruit 88 postmenopausal women across two sites who will be randomized to one of the two laser groups. Participants will all have GSM symptoms and a Vaginal Health Index Score < 15. All participants will receive an active treatment. Each participant will receive three applications of vaginal laser 1 month apart and will be followed up at 1 month, 6 months, and 12 months. Our primary outcomes will look at all changes of GSM symptoms (dryness, dyspareunia, itching, burning, dysuria, frequency, urgency), urinary incontinence (if present), and overall sexual satisfaction. Both subjective and objective means will be used to assess participants. The findings of this trial have the potential to allow clinicians and women suffering from GSM to make an informed decision when opting for a specific laser type. The trial will add to the current growing body of evidence for the safe use of vaginal lasers in GSM as an alternative treatment. We hope this trial will provide robust and long-term data for the safe use of both lasers.