Systematic review and comparator-aware meta-analysis of fractional CO2 vaginal laser for genitourinary syndrome of menopause (GSM), restricted to 9 CO2-only RCTs (from 36 total studies, n=1,709 participants including 407 cancer survivors), with prespecified subgroup analysis by comparator type (sham vs. nonsham controls).
Fractional CO2 laser improved short-term Female Sexual Function Index (FSFI) scores vs. controls overall, but effect sizes were smaller in sham-controlled trials. Vaginal health, urinary, and safety outcomes were inconsistently reported across studies, limiting pooled conclusions.
- Effect attenuation in sham-controlled trials raises concern about placebo and expectancy bias in open-label studies. - Validated minimal clinically important difference (MCID) thresholds for FSFI in this specific GSM population are not established, making clinical interpretation of pooled mean differences uncertain. - Long-term durability, urinary outcomes, oncology-specific safety, and head-to-head comparisons with low-dose vaginal estrogen remain insufficiently studied.
Fractional CO2 laser may offer short-term GSM symptom relief, especially for women who cannot use hormonal therapy, but benefits shrink when placebo effects are controlled—counsel patients accordingly and note that evidence certainty remains low. Until comparative data vs. contemporary low-dose vaginal estrogen are available, hormonal options with stronger evidence should remain first-line where appropriate.
