title: Effect of vulvovaginal estrogen on sensorimotor response of the lower genital tract: a randomized controlled trial.
abstract: OBJECTIVE
  To assess the effect of vulvovaginal estrogen on mucocutaneous sensory threshold and circumvaginal motor strength.
  
  
  METHODS
  Thirty-nine postmenopausal, hypoestrogenic women with mixed lower-genitourinary-tract complaints were placed in four masked treatment arms by permuted-block randomization for 6 weeks. One group received topical estradiol (E2) cream and pelvic muscle biofeedback training, the second received topical E2 cream and sham biofeedback, the third received placebo cream and pelvic muscle biofeedback training, and the fourth received placebo cream and sham biofeedback. Circumvaginal muscle strength was measured by averaging maximum intravaginal pressure (mmHg) generated over a set of four pelvic muscle contractions. Absolute changes in von Frey threshold (mN) and maximum intravaginal pressure (mmHg) over 4 and 6 weeks were reported as summary measures. Of 39 subjects, 30 completed the study.
  
  
  RESULTS
  Topical estradiol cream significantly improved mechanical sensitivity of the vulvar vestibule to von Frey hairs, a -1.2-mN threshold decrease at 4 weeks (F = 10.29; P = .004), and a -1.6-mN threshold decrease at 6 weeks (F = 8.24; P = .009) compared with placebo cream. Stratification by age showed significantly greater improvement in mechanical sensitivity in the older (70-79 years) age group randomized to estrogen cream and a -5.49-mN threshold reduction (F = 17.65; P = .002). Maximum intravaginal pressures during circumvaginal muscle contraction did not differ between estrogen and placebo cream users (F = 0.00; P = .99).
  
  
  CONCLUSIONS
  Improved sensation to mechanical stimuli can result from a rapidly acting, direct effect of topical E2 cream on the vulvar vestibule.
authors.affiliation: Department of Obstetrics and Gynecology, University of Rochester School of Medicine and Dentistry, New York 14642, USA. dfoster@obgyn.rochester.edu
authors.forename: D C
authors.initials: DC
authors.lastname: Foster
authors.forename: M
authors.initials: M
authors.lastname: Palmer
authors.forename: J
authors.initials: J
authors.lastname: Marks
mesh_terms: D000368:Aged; D001676:Biofeedback, Psychology; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D009068:Movement / Q000187:drug effects / Q000502:physiology; D012677:Sensation / Q000187:drug effects / Q000502:physiology; D014621:Vagina / Q000187:drug effects* / Q000502:physiology*; D014844:Vulva / Q000187:drug effects* / Q000502:physiology*
chemical_list: D004967:Estrogens