Cite this page: Ziadie, M. Confined placental mosaicism. PathologyOutlines.com website. http://pathologyoutlines.com/topic/placentaconfinedplacentalmos.html. Accessed November 22nd, 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)
- 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