chorionic villi

Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.
Related to chorionic villi: hydatidiform mole


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 ?
These villi will first be composed, externally, of syncytiotrophoblast and a cytotrophoblast nucleus, and will receive the number of primary chorionic villi. Then, the extraembryonic mesoderm arises from the nucleus of the primary villi, at which point they become known as secondary villi.
Nicolaides, "Histomorphological features of chorionic villi at 10-14 weeks of gestation in trisomic and chromosomally normal pregnancies," Placenta, vol.
Of the remaining seven, six were empty gestational sacs, haemorrhagic samples with MCC or macerated samples with absence of chorionic villi; the last sample was excluded owing to a low DNA amount after DNA extraction (<5 ng/[micro]L).
Intervillous space is narrowed, contains common loci of bleeding, blood clots, fibrinoid fields and cobs, chorionic villi that are close to each other.
Then Handschuh K et al17 compared hCG secretion by primary cultures of VCT and EVCT isolated from the same first trimester human chorionic villi. They proved that invasive EVCT also expressed and secreted high levels of hCG, suggesting a specific paracrine and/or autocrine role for hCG from EVCT origin.17 One way to interpret the present findings is to conclude that invaded by EVCT, uterus wall can be accepted as a rich source of hCG in NIP and this finding cannot be found in EP.
The lack of a gestational sac or chorionic villi within the specimen made an ectopic pregnancy or GTN unlikely.
The most important point about chorionic villi sampling or amniocentesis is the risk of Rh sensitization that it take that mother's Rh- and embryo's Rh+.
Once the needle was adequately placed, the chorionic villi were aspirated with a to and fro jiggling movement of the aspiration needle and a suction force was applied through a syringe.
It occurs when the chorionic villi invade into the myometrium.
The new test can be performed on conventional samples, such as blood and prenatal specimens including amniotic fluid and chorionic villi sampling (CVS).
Cells collected from an amniocentesis and chorionic villi sampling is the only way to know with certainty whether your child has any chromosomal abnormality.