To evaluate the effect of pelvic floor muscle training (PFMT) and CO2 laser on improving symptoms in women with stress urinary incontinence (SUI) by reducing the total score of the International Continence Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) after 12 months of follow-up.

A non-inferiority randomized clinical trial conducted between January 2020 and March 2023 recruited 144 women aged ≥ 18 years with complaints of SUI, including 94 of these, and randomizing 47 in the CO2 laser group (three monthly sessions) and 47 in the PFMT group (12 sessions over 3 months). Sample size calculation considered a mean minimum clinically important difference (MCID) of - 4 of the ICIQ-UI SF total score as well as a standard deviation of 4 used as non-inferiority limit after revising a study comprising these values for SUI women; 43 patients were needed for each group. Women with other urinary symptoms, active urinary or vaginal infection, pelvic surgeries, symptomatic genital prolapse, or a history of other pelvic conditions were excluded. The primary outcome was the mean difference between the total scores of the ICIQ-UI-SF between the groups, and secondary outcomes were the evaluation of pelvic floor symptoms (PFIQ-7), sexual function (FSFI), and subjective improvement post-intervention (PGI-I). Mean difference analysis with a 95% confidence interval was used to identify the non-inferiority margin. Per-protocol and intention-to-treat analyses were considered at a significance level of 5%.

Significant differences were found in the total scores of the ICIQ-UI-SF in both groups (CO2 laser p<0.001, PFMT group p=0.001) after 12 months of follow-up. There was no difference between the groups in sexual function after 12 months of follow-up. A significant reduction in PFIQ-7 was found only in the PFMT group (from 41.73±46.83 to 31.71±43.04; p<0.001). A higher frequency of "slightly worse" and "slightly better" responses was found in the PFMT group, and "much worse," "much better," and "very better" responses were found in the CO2 laser group. Considering a non-inferiority margin of -4, the CO2 laser was non-inferior to PFMT in improving the total score of the ICIQ-UI-SF after 12 months of follow-up (per protocol (0.52[-1.95-3.00]; p=0.675) and intention-to-treat (-0.79 [-3.10-1.53]; p=0.501). Pain during micturition was the most frequent complaint after the first laser session. Vaginal discharge and pain during micturition were more frequent in the second and third laser sessions. After 12 months of follow-up, complaints were much less frequent compared to evaluations after the sessions, with a higher frequency of pain during micturition. No major complications were seen in both groups.

This follow-up study has demonstrated that intravaginal fractional CO2 laser was non-inferior to PFMT after twelve months of treatment. Both groups presented a reduction in the ICIQ-SF scores in both follow-up periods and, it seems that fractional vaginal laser does not lose its efficacy after 12 months. On the other hand, longer follow-ups are needed, as we do not have scientific evidence to recommend when laser revision should be done or when it is the optimal time to undergo other sessions. Moreover, in this study, sexual function did not improve after 12 months of treatment in both groups with no difference between them. 
We have published the data from 3-6 months of follow-up [1] and no differences were seen between the groups. In this update, differences are not perceived. There is another clinical study comparing laser versus PFMT, but it was with erbium [2]. To our knowledge, this is the first RCT comparing CO2 laser versus PFMT. Previous studies compared CO2 laser versus sham controls [3] and data are conflicting.

CO2 laser and PFMT significantly improved the total scores of the ICIQ-UI-SF after 12 months of follow-up. No significant differences were observed in participants' sexual function. CO2 laser was non-inferior to PFMT in improving the ICIQ-UI-SF score after 12 months of follow-up.

Rocha-Rangel SC, Pereira GMV, Juliato CRT, Brito LGO. Laser and Pelvic Floor Muscle Training for Urinary Incontinence: a Randomized Clinical Trial. Urogynecology 2024 doi: 10.1097/SPV.0000000000001516
Fonseca LC, Giarreta FB, Peterson TV et al. A randomized trial comparing vaginal laser therapy and pelvic floor physical therapy for treating women with stress urinary incontinence. Neurourol Urodyn 2023;42(7):1445-1454.
Seki AS, Bianchi-Ferraro AM, Fonseca ES, Sartori MG, Girao MJ, Jarmy-di-Bella ZI. CO2 laser and radiofrequency compared to a sham control group in treatment of stress urinary incontinence (LARF study arm 3). A randomized controlled trial. Int Urogynecol J 2022; 33(12):3535-3542.