Placental gross / microscopic abnormalities, nonneoplastic
Geographic villi

Author: Mandolin Ziadie, M.D. (see Authors page)

Revised: 12 October 2017, last major update October 2011

Copyright: (c) 2002-2017,, Inc.

PubMed Search: Geographic villi

Cite this page: Ziadie, M. Geographic villi. website. Accessed November 18th, 2018.
Definition / general
  • Enlarged, dysmorphic villi with scalloped outlines without associated trophoblastic hyperplasia
  • Associated with chromosomal abnormalities, including trisomies 18, 13, 21; triploidy; XO
Gross images

Images hosted on PathOut server:

Trisomy 18 infant with overlapping digits

Microscopic (histologic) description
  • Enlarged, dysmorphic villi with scalloped outlines
  • Trophoblastic invaginations may be present
  • No / mild trophoblastic hyperplasia is seen