title: Is the placental disk really an ellipse?
abstract: The mean surface shape of placenta is round and common abnormalities of shape are associated with vascular abnormalities and reduced placental functional efficiency. A long-standing approach is to describe shapes as elliptic, and to quantify them by "length" and "breadth". We test this description in two cohorts: National Collaborative Perinatal Project and Pregnancy, Infection and Nutrition Study. We conclude that quantifying placental shape as elliptic is ambiguous and problematic. The "breadth" of the placenta should be interpreted as a combination of two different measurements: placental size and irregularity of the placental surface. It has no intrinsic functional significance.
authors: Department of Mathematics, University of Toronto, 40 St. George St, Toronto, Ontario M5S2E4, Canada.
authors: M
authors: M
authors: Yampolsky
authors: C M
authors: CM
authors: Salafia
authors: D P
authors: DP
authors: Misra
authors: O
authors: O
authors: Shlakhter
authors: J S
authors: JS
authors: Gill
mesh_terms: D001724:Birth Weight; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D009929:Organ Size; D010920:Placenta / Q000033:anatomy & histology* / Q000098:blood supply; D011247:Pregnancy
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