A prospective study examining the anatomic distribution of nerve density in the human vagina.
BACKGROUND
Women possess sufficient vaginal innervation such that tactile stimulation of the vagina can lead to orgasm. However, there are few anatomic studies that have characterized the distribution of nerves throughout the human vagina.


OBJECTIVE
The aim of this prospective study was to better characterize the anatomic distribution of nerves in the adult human vagina. A secondary aim was to assess whether vaginal innervation correlates with the subject's demographic information and sexual function.


METHODS
Full-thickness biopsies of anterior and posterior vagina (proximal and distal), cuff, and cervix were taken during surgery in a standardized manner. Specimens were prepared with hematoxylin and eosin, and S100 protein immunoperoxidase. The total number of nerves in each specimen was quantified. Enrolled patients completed a validated sexual function questionnaire (Female Sexual Function Index, FSFI) preoperatively.


METHODS
A description of vaginal innervation by location and an assessment of vaginal innervation in association with the subject's demographic information and sexual function.


RESULTS
Twenty-one patients completed this study, yielding 110 biopsy specimens. Vaginal innervation was somewhat regular, with no site consistently demonstrating the highest nerve density. Nerves were located throughout the vagina, including apex and cervix. No significant differences were noted in vaginal innervation based on various demographic factors, including age, vaginal maturation index, stage of prolapse, number of vaginal deliveries, or previous hysterectomy. There were no correlations between vaginal nerve quantity and FSFI domain and overall scores. Fifty-seven percent of the subjects had female sexual dysfunction; when compared to those without dysfunction, there were no significant differences in total or site-specific nerves.


CONCLUSIONS
In a prospective study, vaginal nerves were located regularly throughout the anterior and posterior vagina, proximally and distally, including apex and cervix. There was no vaginal location with increased nerve density. Vaginal innervation was not associated with demographic information or sexual function.
Pauls
Rachel
R
Division of Urogynecology and Reconstructive Pelvic Surgery, Good Samaritan Hospital, Cincinnati, OH. Electronic address: rachel_pauls@trihealth.com.
Mutema
George
G
Department of Pathology, Good Samaritan Hospital, Cincinnati, OH.
Segal
Jeffrey
J
Saint Barnabas Medical Center-Center for Urogynecology, Livingston, NJ.
Silva
W Andre
WA
Pacific Northwest Urogynecology-Urogynecology, Federal Way, WA.
Kleeman
Steven
S
Division of Urogynecology and Reconstructive Pelvic Surgery, Good Samaritan Hospital, Cincinnati, OH.
Dryfhout
Vicki
V
Hatton Institute for Research and Education, Good Samaritan Hospital, Cincinnati, OH, USA.
Karram
Mickey
M
Division of Urogynecology and Reconstructive Pelvic Surgery, Good Samaritan Hospital, Cincinnati, OH.
D000328:Adult; D000368:Aged; D001143:Arousal / Q000502:physiology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D009412:Nerve Fibers; D017933:Peripheral Nervous System / Q000166:cytology*; D011446:Prospective Studies; D012016:Reference Values; D012735:Sexual Dysfunction, Physiological / Q000473:pathology*; D014621:Vagina / Q000294:innervation* / Q000601:surgery