Purpose: The clitoris has several histomorphological and functional similarities to the penis. In this study we evaluated spontaneous and evoked electromyography activity in the clitoris.
Materials and methods: We evaluated 11 healthy female volunteers with clitoral electromyography using a concentric needle electrode placed intracorporeally. The hand, foot and genital sympathetic skin responses, and spontaneous electrodermal activity were simultaneously recorded with silver surface electrodes. Another concentric needle electrode was placed subdermally on the mons pubis to differentiate clitoral activity from possible artifact. After recording spontaneous electromyography and electrodermal activity the left median nerve was stimulated to record evoked clitoral activity, and the sympathetic skin response in the hand, foot and genital regions.
Results: There was spontaneous electromyography activity in the corpus clitoris. All dermal sites, including the hand, foot and genital regions, showed spontaneous electrodermal activity. No spontaneous activity was recorded from the subdermal needle electrode. Distraction of attention and coughing increased the amplitude and frequency of spontaneous clitoral electromyography and electrodermal activity at all sites. After stimulating the left median nerve all sites except that of the subdermal needle electrode showed evoked activity.
Conclusions: The demonstrated evoked and spontaneous clitoral electromyography activity seems to indicate a sympathetic tonus of the corpus clitoris, as recorded from the corpus cavernosum of the penis in human males. Clitoral electromyography may be a useful objective assessment tool for evaluating female sexual dysfunction as well as genital autonomic innervation.