Placenta
Placental gross / microscopic abnormalities, nonneoplastic
Confined placental mosaicism

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

Revised: 12 October 2017, last major update September 2011

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

PubMed Search: Confined placental mosaicism [title]

Table of Contents
Definition / general | Etiology
Cite this page: Ziadie, M. Confined placental mosaicism. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/placentaconfinedplacentalmos.html. Accessed November 21st, 2017.
Definition / general
  • Mosaicism (combination of cells with different chromosomal content) confined to placenta and not affecting baby
  • Diagnosed when discrepant results are seen between chorionic villus sampling and amniocentesis / fetal testing (for example, trisomy 16 is seen in the preliminary chorionic villus sampling results but the delivered child has a normal karyotype)
  • Diagnosed in approximately 2% of pregnancies that undergo chorionic villus sampling; may be associated with fetal growth retardation (J Gynecol Obstet Biol Reprod (Paris) 2002;31:2S70)
Etiology
  • Results from mitotic nondisjunction in a trophoblastic / nonfetal cell leading to trisomy in the placental trophoblasts or stroma or from trisomic rescue of a fetus without rescue of the placental cell line