Is Pelvic Floor sEMG a Measure of Women's Sexual Response?

Pelvic floor surface electromyography (sEMG) is often used in the assessment and treatment of individuals with pelvic floor abnormalities to measure muscle tone and neural control of the pelvic floor muscles (PFM); however, little is known about the role of the PFM in sexual arousal.

The aim of this pilot study was to examine whether changes in deep and superficial PFM activity-assessed with sEMG-can be observed during the presentation of sexual stimuli.

Deep PFM sEMG activity was assessed with a vaginal probe. Superficial PFM activity was assessed with sEMG electrodes placed over the bulbocavernosus and perianal muscles. 15 sexually healthy women (mean age 27 years) watched a series of neutral, anxiety-evoking, and sexually explicit films. Continuous subjective sexual arousal was measured using a handheld arousometer.

Changes in microvolts were measured by sEMG sensors, from neutral to anxiety-evoking and neutral to sexually explicit films.

There was an increase in intravaginal and perianal sEMG for both the erotic and anxiety films. Bulbocavernosus sEMG responses did not differ among the 3 films. Concordance between self-reported continuous sexual arousal for the erotic film and bulbocavernosus sEMG (r = 0.349) was not significantly different than concordance using intravaginal sEMG (r = 0.293) or perianal sEMG (r = 0.236).

Understanding more about which parts of the PFM respond specifically to sexual stimuli may have implications for measuring the effects of treatments aimed at improving sexual response in women.

The results of this pilot study provide a preliminary understanding of which pelvic floor muscles respond to sexual stimuli. A limitation of this study was the small sample size.

Taken together, these findings suggest that intravaginal and perianal sEMG respond to erotic stimuli, whereas bulbocavernosal sEMG responses do not. Hannan-Leith MN, Dayan M, Hatfield G, et al. Is Pelvic Floor Surface Electromyography a Measure of Women's Sexual Response? A Pilot Study. J Sex Med 2019;16:70-82.