title: A comparative biomechanical analysis of term fetal membranes in human and domestic species.
abstract: OBJECTIVE
  The purpose of this study was to biomechanically characterize and compare human, porcine, equine, and ovine fetal membranes.
  
  
  METHODS
  Noncontact metrology was used for topographic analyses. Uniaxial tensile testing was performed to resolve specific biomechanical values. Puncture force and radial stresses were determined with biaxial puncture testing. Microstructure and surface tortuosity were analyzed histologically.
  
  
  RESULTS
  Equine and human membranes sustained larger magnitude loading, but ovine and porcine membranes exhibited stronger material properties. Biaxial puncture validated uniaxial results; human and equine groups accommodated the largest loads but lowest stresses. Equine membranes were mostly vascularized; tortuosity was highest in porcine membranes. Species' gestation length was correlated positively with membrane thickness.
  
  
  CONCLUSIONS
  The anatomy of placentation and length of species gestation show distinct relationships to membrane biomechanics. Unlike other species, human fetal membranes do not compensate for structural weakness with a thicker membrane. This finding may explain the high incidence of preterm premature rupture of membranes in humans.
authors.affiliation: Tissue Bioengineering Laboratory, Department of Agricultural and Biological Engineering, TERC and CAVS, Bagley College of Engineering, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Ali
authors.initials: A
authors.lastname: Borazjani
authors.forename: Benjamin C
authors.initials: BC
authors.lastname: Weed
authors.forename: Sourav S
authors.initials: SS
authors.lastname: Patnaik
authors.forename: Jean M
authors.initials: JM
authors.lastname: Feugang
authors.forename: David
authors.initials: D
authors.lastname: Christiansen
authors.forename: Steven H
authors.initials: SH
authors.lastname: Elder
authors.forename: Peter L
authors.initials: PL
authors.lastname: Ryan
authors.forename: Jun
authors.initials: J
authors.lastname: Liao
mesh_terms: D000818:Animals; D005321:Extraembryonic Membranes / Q000502:physiology* / Q000648:ultrastructure; D005260:Female; D006736:Horses; D006801:Humans; D016014:Linear Models; D012756:Sheep; D013314:Stress, Mechanical; D013552:Swine; D013718:Tensile Strength / Q000502:physiology*