title: Alterations in pelvic floor muscles and pelvic organ support by pregnancy and vaginal delivery in squirrel monkeys.
abstract: OBJECTIVE
  The objective of this study was to measure the effects of pregnancy and parturition on pelvic floor muscles and pelvic organ support.
  
  
  METHODS
  Levator ani, obturator internus, and coccygeus (COC) muscle volumes and contrast uptake were assessed by MRI of seven females prior to pregnancy, 3 days, and 4 months postpartum. Bladder neck and cervix position were measured dynamically with abdominal squeezing.
  
  
  RESULTS
  The sides of three paired muscles were similar (p > 0.66). COC volumes were greater (p < 0.004) after parturition than before pregnancy or after recovery. COC contrast uptake increased (p < 0.02) immediately after delivery. Bladder neck position both in the relaxed state and abdominal pressure descended (p < 0.04) after delivery and descended further (p < 0.001) after recovery. Cervical position in the relaxed state before delivery was higher (p < 0.001) than postpartum but was unchanged (p = 0.50) with abdominal pressure relative to delivery.
  
  
  CONCLUSIONS
  In squirrel monkeys, coccygeus muscles demonstrate the greatest change related to parturition, and parturition-related bladder neck descent seems permanent.
authors.affiliation: Department of Obstetrics, Scott and White Memorial Hospital and Clinic, 2401 South 31st Street, Temple, TX 76508, USA. jbracken@swmail.sw.org
authors.forename: Jessica N
authors.initials: JN
authors.lastname: Bracken
authors.forename: Michelle
authors.initials: M
authors.lastname: Reyes
authors.forename: Jilene M
authors.initials: JM
authors.lastname: Gendron
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Pierce
authors.forename: Val M
authors.initials: VM
authors.lastname: Runge
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Kuehl
mesh_terms: D000818:Animals; D002584:Cervix Uteri / Q000473:pathology; D003287:Contrast Media; D005260:Female; D005682:Gadolinium; D008279:Magnetic Resonance Imaging; D018482:Muscle, Skeletal / Q000473:pathology*; D009929:Organ Size; D036801:Parturition; D017773:Pelvic Floor / Q000473:pathology*; D011247:Pregnancy; D012453:Saimiri; D001743:Urinary Bladder / Q000473:pathology
chemical_list: D003287:Contrast Media; D005682:Gadolinium