Corticomotor excitability of the pelvic floor motor representation in females with and without provoked vestibulodynia.

OBJECTIVE: To investigate differences in corticomotor excitability to the pelvic floor muscles (PFMs) between females with and without provoked vestibulodynia (PVD) using transcranial magnetic stimulation (TMS). METHODS: Adult females with and without PVD underwent TMS over the cortical vertex to target motor representations within the central sulcus. Electromyographic responses were recorded from the pubovisceral (PV), bulbocavernosus (BC), and external anal sphincter (EAS) muscles at rest and during PFM contraction. MEP characteristics and SPs were compared between those with and without PVD using independent samples t-tests, with Cohen's d effect sizes computed. RESULTS: Eighty-five females participated (42 PVD, 43 controls). Compared to controls, those with PVD exhibited larger MEP amplitudes in the BC (1477.6 μV vs 478.9 μV, d = -0.64) and EAS (369.1 μV vs 103.3 μV, d = -0.43) at rest and during contraction (2813.1 μV vs 1260.3 μV, d = -0.71; 1034.3 μV vs 340.8 μV, d = -0.54; respectively), shorter MEP onset latencies in the PV (16.5 ms vs 17.2 ms, d = 0.42) and BC (17.0 ms vs 18.3 ms, d = 0.62), and shorter SPs in the EAS (119.4 ms vs 144.2 ms, d = 0.53). CONCLUSION: Those with PVD demonstrated increased corticomotor drive and/or impaired central motor inhibition to the PFMs. SIGNIFICANCE: These findings support the exploration of targeted neuromodulation therapies as a component of therapeutic management of PVD.