title: Influence of the estrous cycle on urodynamic and morphometric measurements of the lower portion of the urogenital tract in dogs.
abstract: OBJECTIVE
  To compare the values of the urodynamic parameters of the lower portion of the urinary tract and vaginourethral measurements obtained during the phases of the estrous cycle in dogs and determine possible functional or anatomic modifications of the lower portion of the urinary tract associated with those phases.
  
  
  METHODS
  7 adult female Beagles.
  
  
  METHODS
  Urethral pressure profilometry, diuresis cystometry, and vaginourethrography were performed in each dog during proestrus; estrus; early, mid, and late diestrus; and early and late anestrus. The maximum urethral pressure (MUP), maximum urethral closure pressure (MUCP), urethral functional and anatomic profile lengths (UFPL and UAPL, respectively), integrated pressure, threshold pressure, threshold volume, compliance, urethral length, and vaginal length and width were measured.
  
  
  RESULTS
  For all measurements, significant interindividual variation was detected. Integrated and threshold pressures, APL, and each morphometric value significantly increased from late anestrus to proestrus. Compared with other phases, MUP, MUCP, and integrated pressure values were significantly lower in estrus and early diestrus; UAPL and UFPL values were significantly lower in late diestrus. At each cycle phase in old dogs, MUP, MUCP, threshold pressure, and vaginal length and width were significantly lower (except in proestrus for vaginal measurements) and threshold volume and compliance values were significantly higher, compared with middle-aged dogs.
  
  
  CONCLUSIONS
  Urodynamic and morphometric measurements of the lower portion of the urogenital tract are affected by the changes in hormonal balance that occur during the estrous cycle. In sexually intact female dogs, estrous phase determination is important for the interpretation of urodynamic data.
authors: Department of Clinical Sciences, College of Veterinary Medicine, University of Liège, 4000 Liège, Belgium.
authors: Annick J
authors: AJ
authors: Hamaide
authors: John P
authors: JP
authors: Verstegen
authors: Frédéric R
authors: FR
authors: Snaps
authors: Karine J
authors: KJ
authors: Onclin
authors: Marc H
authors: MH
authors: Balligand
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001837:Body Weights and Measures / Q000662:veterinary; D004285:Dogs / Q000033:anatomy & histology / Q000502:physiology*; D030762:Estrous Cycle / Q000502:physiology*; D005260:Female; D011312:Pressure; D014563:Urodynamics / Q000502:physiology*; D014566:Urogenital System / Q000033:anatomy & histology* / Q000502:physiology