Predictive Measures of Orgasm in Men, Women, and Spinally-Injured Participants.

Predictive Measures of Orgasm in Men, Women, and Spinally-Injured Participants, Eric Landry, Universite Laval, Canada; Fredrique Courtois, Marie-Pierre Gauthier, Sophie Bergeron, and Marc Belanger, Universite du Quebec a Montreal

To identify the predictive parameters of ejaculation and orgasm, we observed men, women, and spinally-injured (SCI) subjects in direct comparisons during ejaculation or orgasm to characterize female orgasm through objective ejaculation and to compare SCI men with non-SCI men. Physiologic measures of sexual paroxysm included heart rate (HR), blood pressure (BP), plethysmograph or vaginal probe, EMG of the bulbocavernous and abdominal muscles, and H-reflex. Three studies were performed, one with independent tests on men and women, one with repeated measures on men and women, and one with repeated measures on SCI men and non-SCI men. In a laboratory setting, 11 men and 11 women (non-SCI) were asked to self-stimulate to ejaculation or orgasm. Using the same measures, 2 men and 2 women (non-SCI) were repeatedly tested on 6 occasions to control for within-subject variance. Also, 2 SCI and 2 non-SCI men were repeatedly tested on 5 occasions using the FertiCare vibrator. Results showed significant changes from ANOVAs analysis, in men and women, on HR, BP, pletysmograph or vaginal probe, EMG measures of bulbocavernous, and abdominal muscle (frequency and amplitude) at ejaculation or orgasm. H-reflex decreased significantly at ejaculation or orgasm and rapidly returned to baseline. SCI men exhibited a decrease rather than increase in HR at ejaculation, and BP was slower to return to baseline than in non-SCI subjects. H-reflex similarly decreased in men and women at ejaculation and orgasm but slowly returned to baseline for SCI men. This study validates the multiple measures of orgasm and introduces the H-reflex as a valid tool to predict ejaculation in both SCI and non-SCI subjects.