title: Pelvic floor biometry during a first singleton pregnancy and the relationship with symptoms of pelvic floor disorders: a prospective observational study.
abstract: OBJECTIVE
  To assess pelvic floor biometry during pregnancy and the correlation with symptoms of pelvic floor disorders in women.
  
  
  METHODS
  A prospective observational study.
  
  
  METHODS
  Antenatal clinic between August 2009 and May 2011.
  
  
  METHODS
  Nulliparous women in their first pregnancy.
  
  
  METHODS
  Pelvic floor was assessed by translabial ultrasound and symptoms of pelvic floor disorders were explored with a standardised questionnaire at each trimester.
  
  
  METHODS
  Pelvic floor biometry during pregnancy.
  
  
  RESULTS
  A total of 405 (91.6%) women completed the study. As the pregnancy advanced, there was significant descent of the bladder neck (BN), cervix, and anorectal junction. The hiatal area (HA) was significantly enlarged, with a mean increase of 15.1 ± 24.8% at rest, and 24.7 ± 28.5% at Valsalva, at third trimester when compared with first trimester. Risk factors for stress urinary incontinence (SUI) were: descent of BN at Valsalva (OR 3.2, 95% CI 1.2-8.5), increase in HA at pelvic floor contraction (PFMC; OR 1.3, 95% CI 1.0-1.6), and increase in maternal age (OR 1.1, 95% CI 1.0-1.2), at first trimester; increase in HA at PFMC (OR 1.3, 95% CI 1.1-1.5) at second trimester; and descent of BN at rest (OR 2.3, 95% CI 1.1-4.9) and increase in maternal age (OR 1.1, 95% CI 1.02-1.2) at third trimester. Descent of anorectal junction (OR 1.5, 95% CI 1.1-1.9) and increase in HA at rest (OR 1.2, 95% CI 1.0-1.3) were factors for prolapse symptoms at second and third trimester, respectively.
  
  
  CONCLUSIONS
  Pelvic floor changes begin during pregnancy. There was significant descent of the BN, cervix, and anorectal junction, and enlargement of the hiatal area, as the pregnancy advanced. SUI was associated with descent of the BN, and prolapse symptoms were associated with an increase in the hiatal area.
authors.affiliation: Department of Obstetrics & Gynaecology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
authors.forename: S S C
authors.initials: SS
authors.lastname: Chan
authors.forename: R Y K
authors.initials: RY
authors.lastname: Cheung
authors.forename: K W
authors.initials: KW
authors.lastname: Yiu
authors.forename: L L
authors.initials: LL
authors.lastname: Lee
authors.forename: T Y
authors.initials: TY
authors.lastname: Leung
authors.forename: T K H
authors.initials: TK
authors.lastname: Chung
mesh_terms: D000328:Adult; D001699:Biometry; D005260:Female; D006801:Humans; D017773:Pelvic Floor / Q000000981:diagnostic imaging*; D059952:Pelvic Floor Disorders / Q000000981:diagnostic imaging / Q000503:physiopathology*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D014463:Ultrasonography
keywords: Pelvic floor biometry; pelvic floor disorders; pregnancy; translabial ultrasound