title: [Rectal and anal straining pressures in primigravidae].
abstract: OBJECTIVE
  This study intended to evaluate rectal and anal straining pressures in primigravidae, at simulated defecation.
  
  
  METHODS
  The present study is based on 60 women from de Antenatal Care of Santa Casa de Misericórdia - São Paulo. Patients were divided into four groups of 15: a)
  
  
  METHODS
  nuligravidae; b) 1st trimester primigravidae; c) 2nd trimester primigravidae; d) 3rd trimester primigravidae. All patients underwent rectal and anal measurements to obtain: a) Resting rectal pressure; b) Straining rectal pressure; c) Minimal straining anal pressure.
  
  
  RESULTS
  Data was analyzed using statistical methods and reached, the same results: it was observed that the straining rectal pressure decreased from 53.9 +/- 17.9 in control group a to respectively 36.3 +/- 19.6 in group b, 38.1 +/- 16.2 in group c, 30.5 +/- 17.0 in group d, of pregnant women. The minimal anal straining pressure decreased from 46.9 +/- 1.6 in the control group a to 37.5 +/- 15.5 in group b, 32.2 +/- 6.2 in group c , 32.9 +/- 8.7 in group d, during pregnancy.
  
  
  CONCLUSIONS
  Straining rectal and anal pressures both decreased during pregnancy in comparison with the control group, counterbalancing one another to reach a new point of equilibrium during defecation.
authors.affiliation: Departamento de Cirurgia da Santa Casa de São Paulo, S. Paulo, SP. klug@doctor.com
authors.forename: Wilmar Artur
authors.initials: WA
authors.lastname: Klug
authors.forename: Helly Angela Caram
authors.initials: HA
authors.lastname: Aguida
authors.forename: Jorge Alberto
authors.initials: JA
authors.lastname: Ortiz
authors.forename: Chia Bin
authors.initials: CB
authors.lastname: Fang
authors.forename: Peretz
authors.initials: P
authors.lastname: Capelhuchnik
mesh_terms: D000293:Adolescent; D000328:Adult; D001003:Anal Canal / Q000502:physiology*; D016022:Case-Control Studies; D003248:Constipation / Q000209:etiology / Q000503:physiopathology*; D003672:Defecation / Q000502:physiology*; D005260:Female; D020073:Gravidity; D006801:Humans; D008365:Manometry; D011247:Pregnancy; D011264:Pregnancy Trimesters; D011312:Pressure; D012007:Rectum / Q000502:physiology*; D018709:Statistics, Nonparametric; D055815:Young Adult