title: Fractal analysis of the maternal surface of the placenta: preliminary report.
abstract: OBJECTIVE
  The objective of this study was to determine whether the maternal surface of the placenta is fractal, and whether the mean fractal dimension differs according to the gestational age and clinically or pathologically different conditions.
  
  
  METHODS
  Using digitized images of the maternal surface of 75 placentas, fractal dimensions were measured with a fractal analysis software.
  
  
  RESULTS
  The mean fractal dimension of the maternal surface of the placentas significantly exceeded the topological dimension of a surface (= 2). This means that the morphological pattern of the maternal surface fulfills the mathematical definition of fractal structures. Among the three different groups of gestational age, the mean fractal dimension in 22-29 weeks was significantly lower than that in 30-36 and 37-41 weeks (p = 0.022 and 0.014, respectively). Although not significantly different (p = 0.149), in 30-36 weeks the mean fractal dimension of the placentas complicated by pregnancy-induced hypertension (PIH) was greater than that without PIH.
  
  
  CONCLUSIONS
  Fractal geometry, a vocabulary of irregular shapes, can be useful for describing quantitatively the architecture of the maternal surface of the placenta and become a useful tool for analyzing physiological and pathological placental formation mathematically.
authors.affiliation: Department of Obstetrics, Center for Perinatal Medicine, Nagano Children's Hospital, Nagano, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Shiba
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kikuchi
authors.forename: Kikue
authors.initials: K
authors.lastname: Hara
authors.forename: Sorahiro
authors.initials: S
authors.lastname: Sunagawa
authors.forename: Shiro
authors.initials: S
authors.lastname: Yoshida
authors.forename: Kimiyo
authors.initials: K
authors.lastname: Takagi
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Ogiso
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D017709:Fractals; D005865:Gestational Age; D006801:Humans; D008954:Models, Biological; D010781:Photography; D010920:Placenta / Q000033:anatomy & histology / Q000473:pathology*; D010922:Placenta Diseases / Q000473:pathology*; D011247:Pregnancy; D011248:Pregnancy Complications; D012189:Retrospective Studies