Chronic abdominal pain and dyspareunia in endometriosis: pain therapy with a nerve and muscle stimulation device with biofeedback function.

INTRODUCTION: Endometriosis (EM) is frequently associated with chronic pelvic pain (CPP) and dyspareunia, often linked to secondary pelvic floor dysfunction and hypertonicity. To evaluate whether the use of an intravaginal electromyography (EMG) biofeedback and electrostimulation device reduces pain and improves quality of life in patients with EM. METHODS: In this prospective single-arm-real-world clinical study, 201 women with endometriosis used a home-based intravaginal device for three months (up to eight sessions per week). The intervention included two programs: (1) electrical stimulation via a vaginal probe and (2) an EMG biofeedback program for monitoring and training pelvic floor muscle activity. Sessions lasted 30 minutes and intensity was self-adjusted. Pain outcomes were assessed before and after treatment using standardized scales. Paired comparisons were analyzed using the Wilcoxon signed-rank test, and linear regression was used to evaluate associations between frequency of device use and treatment outcomes. The primary outcomes were changes in pelvic floor pain and dyspareunia, with secondary outcomes including dysmenorrhea, dysuria, dyschezia, and cyclic or acyclic abdominal pain. RESULTS: Of the 201 participants, 107 completed the study and 94 dropped out. Pelvic floor pain decreased significantly from 6.0 [3.75-7.25] at baseline to 1.5 [0.0-5.0] after three months (P < .001), and dyspareunia decreased from 7.0 [5.0-8.25] to 5.0 [3.0-7.25] (P < .001). Improvements were also observed in dysmenorrhea (P = .037) and dysuria (P = .014). No significant changes were found in cyclic or acyclic abdominal pain or dyschezia (P > .05). Participants using the device more than three times per week experienced greater reductions in dyspareunia (B = -1.27, 95% CI [-2.38 to -0.21]) compared to those with lower usage, while pelvic floor pain improvements were similar across usage groups. DISCUSSION: Home-based intravaginal EMG biofeedback and electrostimulation may represent a supportive therapeutic option for managing pelvic floor-related pain in EM patients. The prospective design and assessment of a home-based intervention in a real-world setting enhance the clinical relevance of the findings. However, the single-arm design without a control group, the relatively high dropout rate, and the reliance on self-reported outcomes should be considered when interpreting the results. Home-based use of an established CE-certified EMG biofeedback and electrical stimulation device was associated with significant improvements in pelvic floor pain and dyspareunia in women with endometriosis. Controlled studies are warranted to confirm these findings and establish efficacy.