Fallopian tubes
Benign / nonneoplastic
Decidual reaction

Topic Completed: 1 March 2013

Minor changes: 13 December 2019

Copyright: (c) 2002-2019, PathologyOutlines.com, Inc.

PubMed Search: Fallopian tubes - Decidual reaction

Nicole Riddle, M.D.
Jamie Shutter, M.D.
Page views in 2019: 3,000
Page views in 2020 to date: 1,327
Cite this page: Riddle N, Shutter J. Decidual reaction. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/fallopiantubesdecidual.html. Accessed May 30th, 2020.
Definition / general
  • Decidual reaction of subepithelial stroma similar to that seen in endometrium
  • Epithelium is often atrophic
Clinical features
  • Common at time of cesarean section (with accompanying tubal ligation) or after hormonal therapy
  • May occur more often than generally believed, 12% incidence in one study (Am J Pathol 1943;19:1043)
  • Serosal decidua formation common finding (5.5%) after tubal ligation (Am J Surg Pathol 1987;11:526)
Case reports
  • 41 year old woman with stromal and epithelial changes in fallopian tube following hormonal therapy (Hum Pathol 1980;11:583)
  • 41 year old woman with omentum sampling post caesarean section for term delivery without complications (Case of Week #285)
Microscopic (histologic) description
  • Small nodules of decidual cells covered by flattened or inflamed epithelium; affects stromal cells of lamina propria
Microscopic (histologic) images

Case of the Week #285

Various images

left: PR, right: vimentin

AFIP images

Various images

Images hosted on other servers:

Every mucosal fold is distended
by decidual cells; advanced
involution is present, leaving
most of the folds partially cystic


Distended mucosal fold is attached to wall by a relatively narrow pedicle; tubal
epithelium is flattened by compression; extensive involution is present, leaving
the fold partially cystic; remaining decidual cells are in various stages of
degeneration and vacuolated cells and ring forms are evident


Two structurally intact
decidual cells are present
at tip of a mucosal fold;
the covering epithelium is flattened


Mucosal fold is distended by
structurally well preserved decidual
cells, which vary in size and shape;
covering tubal epithelium is flattened


Group of decidual cells in a peritoneal evagination near
the mesosalpinx has vacuolated cells and ring forms; also
intact but flattened covering layer of serosal mesothelium;
overlies cuboidal mesothelium detached from underlying tissue

Involuting decidual
cells, mostly peculiar,
somewhat irregular
ring form

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