title: 3-D volumetric and vascular analysis of the urethrovaginal space in young women with or without vaginal orgasm.
abstract: BACKGROUND
  The existence of the G-spot is controversial.
  
  
  OBJECTIVE
  To evaluate, by the use of three-dimensional (3-D) ultrasonography, the anatomic structures of the urethrovaginal space.
  
  
  METHODS
  Nineteen (Group I) eumenorrheic young women who experienced, and 20 (Group II) who did not experience a vaginal orgasm underwent two-dimensional (2-D) and 3-D ultrasonography and color Doppler analysis of the urethrovaginal space and of the clitoris during the early follicular phase of the menstrual cycle.
  
  
  METHODS
  2-D ultrasonographic evaluation of the urethrovaginal space, and color Doppler evaluation of the urethrovaginal main feeding artery and dorsal clitoral arteries; 3-D volume calculation of the urethrovaginal space, and 3-D power Doppler analysis of vascular indices of the urethrovaginal space and clitoral body (vascularization index, flow index, vascularization flow index); hormonal evaluation.
  
  
  RESULTS
  The 3-D reconstruction of the urethrovaginal space demonstrated a gland-like aspect with small feeding vessels. The total length (19.1 + or - 2.7 mm vs. 17.5 + or - 2.1 mm; P = 0.047), measured with 2-D ultrasound, and the 3-D mean volume (0.59 + or - 0.13 mL vs. 0.26 + or - 0.07 mL; P < 0.001) of the structures contained in the urethrovaginal space were significantly higher in Group I than in Group II. The mean time since the last intercourse was 31 + or - 9 hours in Group I and 18 + or - 3 hours (P = 0.033) in Group II. The urethrovaginal space vascularization, the clitoral volume and vascularization, and the circulating hormonal values did not significantly differ among the two groups. The mean volume of the structures contained in the urethrovaginal space was correlated with time since intercourse (r = 0.685; P = 0.021) and with serum testosterone (r = 0.637; P = 0.032) and androstenedione (r = 0.744; P = 0.011).
  
  
  CONCLUSIONS
  The structures we observed in the urethrovaginal space have a gland-like aspect and their volume is correlated with both serum androgen concentrations and time since intercourse.
authors.affiliation: Department of Gynecology and Pathophysiology of Human Reproduction, Alma Mater Studiorum-University of Bologna, Via Massarenti, Bologna, Italy. cesare.battaglia@unibo.it
authors.forename: Cesare
authors.initials: C
authors.lastname: Battaglia
authors.forename: Rossella Elena
authors.initials: RE
authors.lastname: Nappi
authors.forename: Fulvia
authors.initials: F
authors.lastname: Mancini
authors.forename: Stefania
authors.initials: S
authors.lastname: Alvisi
authors.forename: Simona
authors.initials: S
authors.lastname: Del Forno
authors.forename: Bruno
authors.initials: B
authors.lastname: Battaglia
authors.forename: Stefano
authors.initials: S
authors.lastname: Venturoli
mesh_terms: D000328:Adult; D000735:Androstenedione / Q000097:blood; D001783:Blood Flow Velocity / Q000502:physiology; D002987:Clitoris / Q000098:blood supply*; D003075:Coitus / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D009948:Orgasm / Q000502:physiology*; D011673:Pulsatile Flow; D012984:Software; D013739:Testosterone / Q000097:blood; D014463:Ultrasonography; D018615:Ultrasonography, Doppler, Color; D014521:Urethra / Q000098:blood supply* / Q000000981:diagnostic imaging*; D014621:Vagina / Q000098:blood supply* / Q000000981:diagnostic imaging*
chemical_list: D013739:Testosterone; D000735:Androstenedione