chorionic villi

(redirected from Chorionic villous)


pertaining to the chorion.
chorionic villi numerous branching projections from the external surface of the chorion that provide for exchange between the maternal and fetal circulation. Oxygen and nutrients in the maternal blood diffuse through the walls of the villi and enter the blood of the embryo or fetus. Carbon dioxide and waste products diffuse from blood in the fetal capillaries through the walls of the villi into the maternal blood. See also chorionic villus sampling.


 [vil´us] (L.)
a small vascular process or protrusion, as from the free surface of a membrane.
arachnoid villi microscopic projections of the arachnoid into some of the venous sinuses.
chorionic villi see chorionic villi.
intestinal villi multitudinous threadlike projections covering the surface of the mucous membrane lining the small intestine, serving as the sites of absorption of fluids and nutrients.
synovial villi slender projections from the surface of the synovial membrane into the cavity of a joint; called also haversian glands.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

cho·ri·on·ic vil·li

vascular processes of the chorion of the embryo entering into the formation of the placenta.
Farlex Partner Medical Dictionary © Farlex 2012

cho·ri·on·ic vil·li

(kōr'ē-on'ik vil'ī)
Vascular processes of the chorion of the embryo entering into the formation of the placenta.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

chorionic villi

The finger-like projections from the CHORION into the wall of the womb at the site at which the PLACENTA is developing. Since both the chorionic villi and the embryo are derived from the same fertilized ovum a sample of the former provides material for genetic studies of the latter. Chorionic villus sampling has become an important method of early pre-natal screening for genetic defects.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

Chorionic villi

Microscopic, finger-like projections that emerge from the outer sac which surrounds the developing baby. Chorionic villi are of fetal origin and eventually form the placenta.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
First trimester development of human chorionic villous vascularization studies with CD34 immunohistochemistry.
It also showed subendothelial fibrin deposition in stem villous blood vessels, chorionic villous hypervascularity, and a small subchorionic placental infarct.
Tasleem S, Tasleem H, Siddiqui MA, Adil MM, Rashid Y: Prenatal diagnosis of -Thalassaemia by Chorionic Villous Sampling.
(39) The mechanism(s) by which Hofbauer cell hyperplasia occurs in response to an inciting factor is, at least in part, the result of proliferation of these cells within the chorionic villous stroma.
Prenatal genetic counselling with the offer of prenatal testing by chorionic villous sampling (CVS) or amniocentesis was recommended for future pregnancies in view of the mother's advanced maternal age, which would increase her risk for another baby with a chromosome abnormality.
When the familial mutation is known, genetic counseling can be done and if required, prenatal diagnosis can be done at early stage of pregnancy by chorionic villous biopsy.
With improved screening methods, there is a need for diagnostic tests such as a chorionic villous sample and amniocentesis to confirm or exclude aneuploidy.
In harlequin icthyosis prenatal diagnosis by fetal skin biopsy and ultrasonography helps for precise diagnosis by taking chorionic villous sampling.
In the past several decades, prenatal abnormalities were mainly detected by maternal serum analysis, amniocentesis, cordocenthesis and chorionic villous sampling2.