title: Influence of sildenafil on genital engorgement in women with female sexual arousal disorder.
abstract: BACKGROUND
  We previously described dynamic, noncontrast magnetic resonance imaging (MRI) of the female genitalia as a reproducible, nonintrusive, objective means of quantifying sexual arousal response in women without sexual difficulties. These studies showed an increase in clitoral engorgement ranging from 50 to 300% in healthy women during sexual arousal.
  
  
  OBJECTIVE
  This study sought to evaluate the genital arousal response in women with female sexual arousal disorder (FSAD) after administration of sildenafil and placebo. We performed a multicenter, double-blind, placebo-controlled, cross-over study to assess the clitoral engorgement response using dynamic MRI in women with FSAD after administering sildenafil and placebo followed by audiovisual sexual stimulation (AVSS).
  
  
  METHODS
  Nineteen premenopausal women with FSAD underwent two MRI sessions. Subjects were randomized to receive either (i) sildenafil 100 mg during the first session followed by placebo during the second session, or (ii) placebo followed by sildenafil. During each session, baseline MR images were obtained while subjects viewed a neutral video. Subjects then ingested sildenafil or placebo. After 30 minutes, a series of MRIs were obtained at 3-minute intervals for 10 time points while subjects viewed AVSS.
  
  
  METHODS
  A positive sexual arousal response was achieved if clitoral volume increased ≥50% from baseline.
  
  
  RESULTS
  Thirteen of 19 (68%) subjects achieved a ≥50% increase in clitoral engorgement from baseline when administered sildenafil or placebo 30 minutes after dose administration. At 60 minutes after administration, 17/19 (89%) subjects receiving sildenafil and 16/19 (84%) subjects receiving placebo had responded (P value 0.3173).
  
  
  CONCLUSIONS
  Sildenafil did not augment the genital response in women with FSAD. Secondarily, a majority of women in this study did not have impaired clitoral engorgement as measured by MRI, suggesting that FSAD is not predominantly a disorder of genital engorgement.
authors.affiliation: University of Washington, Seattle, WA 98195-6510, USA.
authors.forename: Laura S
authors.initials: LS
authors.lastname: Leddy
authors.forename: Claire C
authors.initials: CC
authors.lastname: Yang
authors.forename: Bronwyn G
authors.initials: BG
authors.lastname: Stuckey
authors.forename: Maria
authors.initials: M
authors.lastname: Sudworth
authors.forename: Scott
authors.initials: S
authors.lastname: Haughie
authors.forename: Stefan
authors.initials: S
authors.lastname: Sultana
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Maravilla
mesh_terms: D000328:Adult; D001143:Arousal / Q000187:drug effects* / Q000502:physiology; D002987:Clitoris / Q000098:blood supply*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D058986:Phosphodiesterase 5 Inhibitors / Q000008:administration & dosage*; D010879:Piperazines / Q000008:administration & dosage*; D011687:Purines / Q000008:administration & dosage; D020018:Sexual Dysfunctions, Psychological / Q000188:drug therapy* / Q000503:physiopathology; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000008:administration & dosage*
chemical_list: D058986:Phosphodiesterase 5 Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate