Inflammation predicts sexual arousability in healthy women

BACKGROUND: Though many women report sexual arousal difficulties, the mechanisms driving these difficulties are unclear. Sexual response relies on a host of psychophysiological processes that have bidirectional relationships with inflammation. Additionally, chronic inflammation may impair genital blood flow, which in turn may impact sexual arousal. C-reactive protein (CRP) is an acute-phase marker of inflammation produced in response to cytokine signaling throughout the body, which makes it a useful marker of systemic inflammation. AIM: The present study examined interactions between inflammation and women's sexual arousal. METHODS: CRP, self-reported frequency of partnered sexual activity, and subjective and vaginal arousal were assessed in 91 healthy, pre-menopausal women. Data were collected during a single laboratory session. MAIN OUTCOME MEASURES: Subjective sexual arousal and vaginal pulse amplitude (a measure of vaginal arousal) were the main outcome measures. RESULTS: Change in subjective sexual arousal in response to a sexual film was unaffected by baseline CRP and sexual frequency. However, there were significant interactions between inflammation and sexual frequency in predicting vaginal arousal during the sexual film. Among women reporting more frequent sexual activity, higher CRP predicted lower magnitude arousal response and longer time to maximum vaginal arousal. Among women reporting less frequent sex, higher CRP predicted shorter time to maximum arousal and greater magnitude of arousal response. Controlling for cortisol strengthened the effects seen for time to maximum vaginal arousal but weakened those observed for percent change. CONCLUSIONS: Among healthy young women, higher CRP may be associated with vaginal arousal, but not subjective sexual arousal. Specifically, our results suggest that higher baseline CRP is associated with lower genital sexual arousal for women who have sex frequently, which is consistent with clinical evidence that elevated inflammation can be detrimental to sexual function.