Comparative efficacy of low- vs. high‐frequency endovaginal electrostimulation combined with pelvic floor muscle training on pelvic floor bioelectrical activity in young, healthy women: a preliminary, single-center, randomized controlled trial

Background Pelvic floor dysfunctions can significantly affect women’s quality of life. Endovaginal electrostimulation is a well-established conservative therapy; however, the optimal stimulation frequency remains uncertain, particularly as a preventive measure in healthy populations. This study aimed to compare the effects of 10 Hz versus 50 Hz endovaginal electrostimulation, when combined with pelvic floor muscle (PFM) training, on the bioelectrical activity of PFM in young women without urinary–genital dysfunction. Methods In this prospective, single-blinded, randomized controlled trial, 45 healthy women aged 18–28 were randomized into three groups of n = 15 each: Study group I, receiving 10 Hz endovaginal electrostimulation plus pelvic floor exercises; Study group II, receiving 50 Hz endovaginal electrostimulation plus pelvic floor exercises; and the Control group, performing pelvic floor exercises only. All 45 women completed the intervention and follow-up and were analyzed: Study group I, n = 15; Study group II, n = 15; Control group, n = 15. Interventions were administered thrice weekly over eight weeks. Surface electromyography (sEMG) measured resting and functional bioelectrical activity in supine and standing positions at baseline (M1), immediately post-intervention (M2), and at one- (M3) and three-months follow-up (M4). Results Resting sEMG activity decreased over time, particularly in the supine position. However, mixed-effects analyses did not show significant group × time interactions, indicating no statistically confirmed differences in trajectories of change between the intervention and control groups. No clear differences were observed between the 10 Hz and 50 Hz electrostimulation groups. Conclusions Time-related reductions in resting pelvic floor muscle bioelectrical activity were observed, but these changes were not significantly different between groups. The findings do not support a superior effect of either electrostimulation frequency or of combining electrostimulation with pelvic floor muscle exercises compared with exercises alone. Further studies with larger samples are warranted. Trial registration Registration no. ISRCTN81464370. Registration date: 25/07/2022. https://www.isrctn.com/ISRCTN81464370